test: cover readSize branches in Context

Co-authored-by: Cursor <[email protected]>

.all-contributorsrc

@@ -838,6 +838,15 @@
       "contributions": [
         "code"
       ]
+    },
+    {
+      "login": "spokodev",
+      "name": "spokodev",
+      "avatar_url": "https://avatars.githubusercontent.com/u/239690017?v=4",
+      "profile": "https://github.com/spokodev",
+      "contributions": [
+        "code"
+      ]
     }
   ],
   "contributorsPerLine": 7,

.cursor/rules/architecture.mdc

@@ -1,17 +0,0 @@
----
-description: Architecture overview for liquidjs internals
-alwaysApply: true
----
-
-## Async/sync duality via generators
-
-All core logic is written once as a `Generator` function (`function *`). Use `yield` where you'd normally `await` a potentially async value.
-
-- `toPromise(generator)` drives it **asynchronously** — awaits yielded promises.
-- `toValueSync(generator)` drives it **synchronously** — passes yielded values through as-is.
-
-Never duplicate logic into separate async and sync methods. A single generator serves both paths.
-
-When wrapping an async+sync function pair (e.g. `contains`/`containsSync`, `exists`/`existsSync`, `readFile`/`readFileSync`), use `toLiquidAsync(asyncFn, syncFn?)` which returns a `LiquidAsync<F>` — one function that picks the sync or async implementation based on a leading `sync: boolean` arg. Then `yield` the result inside a generator to let the driver handle it in both modes.
-
-See `src/util/async.ts`.

.cursor/rules/conventions.mdc

@@ -1,6 +0,0 @@
----
-description: Project conventions for liquidjs
-alwaysApply: true
----
-
-- Keep edits minimal: change only what the task requires, match existing style.

.cursor/rules/testing.mdc

@@ -1,17 +0,0 @@
----
-description: Testing conventions — e2e uses built dist, integration uses src
-globs: test/**/*.ts
-alwaysApply: false
----
-
-# Testing
-
-## End-to-end tests (`test/e2e`)
-
-- **Use the built package**, not TypeScript sources under `src/`.
-- Import the public API from the package root (for example `import { Liquid } from '../..'`), which resolves through `package.json` to **`dist/`** (`main`, `module`, etc.).
-- **Avoid** `import … from '../../src/liquid'` (or other `src/` paths) in `test/e2e/**` so e2e matches what consumers get from npm and you do not depend on an unbuilt tree.
-
-## Integration and unit tests
-
-- Tests under `test/integration/`, `src/**/*.spec.ts`, and similar may import from **`src/`** when the suite is meant to run against the current TypeScript sources (typical for this repo’s Jest setup).

.github/workflows/build.yml

@@ -22,7 +22,7 @@ jobs:
       - name: Setup Node.js
         uses: actions/setup-node@v3
         with:
-          node-version: '20'
+          node-version: 'latest'
       - name: Install dependencies
         run: npm ci
       - name: Build

.github/workflows/coverage.yml

@@ -12,7 +12,7 @@ jobs:
       - name: Setup Node.js
         uses: actions/setup-node@v3
         with:
-          node-version: '22'
+          node-version: 'latest'
       - name: Install dependencies
         run: npm ci
       - name: Test

.github/workflows/docs.yml

@@ -12,7 +12,7 @@ jobs:
       - name: Setup Node.js
         uses: actions/setup-node@v3
         with:
-          node-version: '20'
+          node-version: 'latest'
       - name: Build
         run: |
           npm ci

.github/workflows/lint.yml

@@ -12,7 +12,7 @@ jobs:
       - name: Setup Node.js
         uses: actions/setup-node@v3
         with:
-          node-version: '20'
+          node-version: 'latest'
       - name: Install dependencies
         run: npm ci
       - name: Lint

.github/workflows/performance.yml

@@ -17,7 +17,7 @@ jobs:
       - name: Setup Node.js
         uses: actions/setup-node@v3
         with:
-          node-version: '20'
+          node-version: 'latest'
       - name: Download artifacts
         uses: actions/download-artifact@v4
         with:

.github/workflows/release.yml

@@ -24,12 +24,7 @@ jobs:
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
-        run: |
-          if [ ${{ github.ref == 'refs/heads/master' }} ]; then
-            npx semantic-release
-          else
-            npx semantic-release --dry-run
-          fi
+        run: npx semantic-release
       - name: Archive npm failure logs
         uses: actions/upload-artifact@v4
         if: failure()

.github/workflows/test.yml

@@ -7,20 +7,10 @@ jobs:
       matrix:
         os: [ubuntu-latest]
         timezone: [Etc/GMT, Asia/Shanghai, America/New_York]
-        node-version: [22]
+        node-version: [latest]
         include:
-          - os: macos-latest
-            timezone: America/New_York
-            node-versoin: 22
           - os: ubuntu-latest
-            timezone: Etc/GMT
-            node-version: 20
-          - os: ubuntu-latest
-            timezone: Asia/Shanghai
-            node-version: 18
-          - os: ubuntu-latest
-            timezone: Asia/Shanghai
-            node-version: 16
+            node-version: lts/*
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout
@@ -39,7 +29,7 @@ jobs:
           name: dist-${{ matrix.os }}
           path: dist
       - name: Run Test
-        run: TZ=${{ matrix.timezone }} npm test
+        run: TZ=${{ matrix.timezone || 'Etc/GMT' }} npm test
       - name: Archive npm failure logs
         uses: actions/upload-artifact@v4
         if: failure()
@@ -57,7 +47,7 @@ jobs:
       - name: Setup Node.js
         uses: actions/setup-node@v3
         with:
-          node-version: 22
+          node-version: latest
       - name: Download artifacts
         uses: actions/download-artifact@v4
         with:

.gitignore

@@ -11,9 +11,11 @@ coverage/
 node_modules/
 
 # tmp
+.local/
 docs/themes/navy/source/js/liquid.browser.min.js
 docs/themes/navy/layout/partial/all-contributors.swig
 docs/themes/navy/layout/partial/financial-contributors.swig
+docs/themes/navy/layout/partial/used-by.swig
 dist/
 demo/*/yarn.json
 

.releaserc.cjs

@@ -0,0 +1,50 @@
+const gitPlugin = [
+  '@semantic-release/git',
+  {
+    assets: ['package.json', 'package-lock.json', 'CHANGELOG.md'],
+    message: 'chore(release): ${nextRelease.version} [skip ci]\n\n${nextRelease.notes}'
+  }
+]
+
+const githubPlugin = [
+  '@semantic-release/github',
+  {
+    assets: [
+      { path: 'dist/*.umd.js', label: 'liquid.js' },
+      { path: 'dist/*.min.js', label: 'liquid.min.js' },
+      { path: 'dist/*.min.js.map', label: 'liquid.min.js.map' }
+    ]
+  }
+]
+
+// next is branch-protected (PR-only); skip @semantic-release/git there and publish to npm only.
+const onMaster = process.env.GITHUB_REF === 'refs/heads/master'
+const onNext = process.env.GITHUB_REF === 'refs/heads/next'
+
+// On next, breaking changes are v11 WIP — bump alpha prerelease only, not major.
+const commitAnalyzer = onNext
+  ? ['@semantic-release/commit-analyzer', {
+      releaseRules: [
+        { breaking: true, release: 'patch' }
+      ]
+    }]
+  : '@semantic-release/commit-analyzer'
+
+const basePlugins = [
+  commitAnalyzer,
+  '@semantic-release/release-notes-generator',
+  '@semantic-release/changelog',
+  '@semantic-release/npm'
+]
+
+module.exports = {
+  branches: [
+    'master',
+    { name: 'next', prerelease: 'alpha' }
+  ],
+  plugins: [
+    ...basePlugins,
+    ...(onMaster ? [gitPlugin] : []),
+    githubPlugin
+  ]
+}

AGENTS.md

@@ -0,0 +1,94 @@
+# LiquidJS
+
+A simple, expressive, extensible Liquid template engine for JavaScript — Shopify, Jekyll and GitHub Pages compatible, for Node.js, browsers, and the CLI, with TypeScript support. TypeScript in `src/`, bundles in `dist/`. Docs site in `docs/` (Hexo, `navy` theme).
+
+## Layout
+
+| Path | Contents |
+| --- | --- |
+| `src/parser`, `src/render`, `src/tags`, `src/filters` | Template parse and render |
+| `src/context`, `src/template`, `src/tokens` | Scope, templates, token stream |
+| `src/util/async.ts` | `toPromise`, `toValueSync`, `toLiquidAsync` |
+| `test/` | Jest |
+| `docs/source/` | Doc markdown; sidebar in `docs/source/_data/sidebar.yml` |
+| `docs/themes/navy/` | Layout, CSS, JS |
+| `.local/` | Scratch, repro, PoC (gitignored) |
+
+## Commands
+
+```
+npm run build          # after src/ changes, before npm test
+npm test
+npm run lint
+npm run check          # build + build:docs + test + lint + perf:diff (manual)
+npm run build:docs
+cd docs && npm start   # http://localhost:4000
+npm run perf:diff
+```
+
+PR CI (`pull_request`): build, lint, test, coverage, performance. Docs build runs on push to `master` only.
+
+PR titles: conventional format (`feat:`, `fix:`, `docs:`, …) — checked by CI. Releases on `master` use semantic-release from merged commits.
+
+Backward-compatible API changes expected unless doing an intentional major break.
+
+## Architecture
+
+All core logic is one `function *` per feature. Use `yield` where you'd normally `await` a potentially async value.
+
+- `toPromise(generator)` — async driver; awaits yielded promises
+- `toValueSync(generator)` — sync driver; passes yielded values through as-is
+
+Never duplicate logic into separate async and sync methods. One generator serves both paths.
+
+When wrapping an async+sync pair (e.g. `contains`/`containsSync`, `readFile`/`readFileSync`), use `toLiquidAsync(asyncFn, syncFn?)` — returns a `LiquidAsync<F>` that picks sync or async via a leading `sync: boolean` arg. `yield` the result inside a generator. See `src/util/async.ts`.
+
+## Style
+
+Make minimal changes only. Avoid sweeping edits. Always check after you made changes.
+
+- Change only what the task requires. No drive-by refactors, test harnesses, or extra files unless asked.
+- Match existing patterns in the file you edit.
+- Repro, PoC, and scratch files go in `.local/` — not tracked `poc/` folders or one-off scripts under `docs/`.
+
+### Comments
+
+- Do not add narrative comments. Code should be clear from structure and naming; if it needs explanation, refactor instead.
+- Comments follow existing repo usage only: non-obvious invariants, `@deprecated`, JSDoc on public API where TypeDoc needs it. Not for explaining changes to the author, migration history, or restating what the code already says.
+- Comments document the code; they do not fix unclear code.
+
+### Tests
+
+- Assert observable behavior, not internal implementation details.
+- Avoid duplicate coverage; keep test diffs minimal.
+- **E2E** (`test/e2e/`): import from the package root (resolves to `dist/` via `package.json`). Do not import from `src/` — e2e must match what npm consumers get.
+- **Integration/unit** (`test/integration/`, etc.): may import from `src/` against current TypeScript sources.
+
+### Docs site
+
+- Reuse existing asset paths under `docs/source/` and `docs/themes/navy/` — no new asset directories unless asked.
+- Front matter `title:` is plain text (no backticks).
+- `docs/source/llms.txt` — deployed to https://liquidjs.com/llms.txt for web agents (llms.txt spec).
+- After theme/markdown changes: build or serve locally, check in a browser (light and dark), not only curl or editor preview.
+
+### README
+
+- Research original sources before reordering contributors, logos, or lists.
+
+## Verify
+
+- Do not commit, push, amend, or open a PR unless asked.
+- After changes: verify yourself via CLI or UI (tests, `cd docs && npm start`, browser) before reporting done. Do not tell the user to check instead.
+- Before push on sweeping changes: run `npm run check`.
+- Confirm facts from `.github/workflows`, `package.json`, and library docs — not stale human docs or assumptions.
+- When replacing or integrating a library: read its docs and understand what the previous setup did before changing behavior.
+
+### Security fixes
+
+- Reproduce on current `master` first. Smallest fix that addresses the reported issue.
+- If Shopify/Ruby Liquid behaves the same, document unsafe usage in filter/docs instead of changing behavior.
+
+## Docs
+
+- Published: https://liquidjs.com
+- Repo agent instructions: this file (`AGENTS.md`)

CHANGELOG.md

@@ -1,3 +1,17 @@
+## [10.27.1](https://github.com/harttle/liquidjs/compare/v10.27.0...v10.27.1) (2026-06-23)
+
+
+### Bug Fixes
+
+* improve round function; improvement to [#873](https://github.com/harttle/liquidjs/issues/873) ([#901](https://github.com/harttle/liquidjs/issues/901)) ([956b51e](https://github.com/harttle/liquidjs/commit/956b51ea953eb52d9eba7409b7f51e379023fec4))
+* **security:** charge pop filter allocation to memoryLimit ([#907](https://github.com/harttle/liquidjs/issues/907)) ([8a0c74a](https://github.com/harttle/liquidjs/commit/8a0c74a7fcb1671aa1dcb71ec82ba0602dc90d04))
+* **strip_html:** infinite loop for strip_html ([5c3522f](https://github.com/harttle/liquidjs/commit/5c3522f33928aae66f0fe85c36e1d9015c768fe2))
+
+
+### Performance Improvements
+
+* **parser:** memoize createTrie to avoid rebuilding tries per Tokenizer ([#911](https://github.com/harttle/liquidjs/issues/911)) ([3a0d80d](https://github.com/harttle/liquidjs/commit/3a0d80d1f4526af0fbca2bb2e0a9c51669d2fd3e))
+
 # [10.27.0](https://github.com/harttle/liquidjs/compare/v10.26.0...v10.27.0) (2026-05-15)
 
 

README.md

@@ -1,72 +1,86 @@
-# liquidjs
+# LiquidJS
+
+A simple, expressive, extensible Liquid template engine for JavaScript — Shopify, Jekyll and GitHub Pages compatible, for Node.js, browsers, and the CLI, with TypeScript support.
+
 [![npm version](https://img.shields.io/npm/v/liquidjs.svg?logo=npm&style=flat-square)](https://www.npmjs.org/package/liquidjs)
 [![npm downloads](https://img.shields.io/npm/dm/liquidjs.svg?style=flat-square)](https://www.npmjs.org/package/liquidjs)
-[![Coverage](https://img.shields.io/coveralls/harttle/liquidjs.svg?style=flat-square)](https://coveralls.io/github/harttle/liquidjs?branch=master)
 [![Build Status](https://img.shields.io/github/actions/workflow/status/harttle/liquidjs/ci-build.yml?branch=master&style=flat-square)](https://github.com/harttle/liquidjs/actions/workflows/ci-build.yml?query=branch%3Amaster)
-[![DUB license](https://img.shields.io/dub/l/vibe-d.svg?style=flat-square)](https://github.com/harttle/liquidjs/blob/master/LICENSE)
-[![semantic-release](https://img.shields.io/badge/%20%20%F0%9F%93%A6%F0%9F%9A%80-semantic--release-e10079.svg?style=flat-square)](https://github.com/harttle/liquidjs)
+[![Coverage](https://img.shields.io/coveralls/harttle/liquidjs.svg?style=flat-square)](https://coveralls.io/github/harttle/liquidjs?branch=master)
+[![License: MIT](https://img.shields.io/github/license/harttle/liquidjs?style=flat-square)](https://github.com/harttle/liquidjs/blob/master/LICENSE)
 
-A simple, expressive and safe [Shopify][shopify/liquid] / GitHub Pages compatible template engine in pure JavaScript.
-**The purpose of this repo** is to provide a standard Liquid implementation for the JavaScript community so that [Jekyll sites](https://jekyllrb.com), [GitHub Pages](https://pages.github.com/) and [Shopify templates](https://themes.shopify.com/) can be ported to Node.js without pain.
+[Documentation][doc] · [Playground](https://liquidjs.com/playground.html) · [Setup guide][setup] · [Contributing][contribution]
 
-* [Documentation][doc]
-* Please star [LiquidJS on GitHub][github]!
-* Financial support via [GitHub Sponsors](https://github.com/sponsors/harttle).
+<a href="https://liquidjs.com/playground.html">
+  <img src="docs/source/playground-demo.gif" alt="LiquidJS playground: edit a template and context, see live HTML output" width="980" style="display: block; margin: 0 auto;" />
+</a>
 
-<p align="center"><a href="https://liquidjs.com"><img height="155px" width="155px" src="https://liquidjs.com/icon/mstile-310x310.png" alt="logo"></a></p>
+<p align="center"><sub>Try the <a href="https://liquidjs.com/playground.html">online playground</a>.</sub></p>
 
-## What's it like?
+## Quick start
 
-Basically there're two types of Liquid syntax: tags enclosed by `{% %}` and outputs enclosed by `{{ }}`. A Liquid template looks like:
+```js
+import { Liquid } from 'liquidjs'
 
-```liquid
-{% if username %}
-  {{ username | append: ", welcome to LiquidJS!" | capitalize }}
-{% endif %}
+const engine = new Liquid()
+const html = await engine.parseAndRender(
+  'Hello, {{ name | capitalize }}!',
+  { name: 'liquid' }
+)
+//=> 'Hello, Liquid!'
 ```
 
-[A live demo](https://liquidjs.com/playground.html) is also available and here's a [quick tutorial](https://liquidjs.com/tutorials/intro-to-liquid.html) for Liquid syntax.
-
-
 ## Installation
 
-Install from npm in Node.js:
+**Node.js**
 
 ```bash
 npm install liquidjs
 ```
 
-Or use the UMD bundle from jsDelivr:
+**Browser** (jsDelivr UMD bundle)
 
 ```html
 <script src="https://cdn.jsdelivr.net/npm/liquidjs/dist/liquid.browser.min.js"></script>
 ```
 
-Or render directly from CLI using npx:
+**CLI**
 
 ```bash
-npx liquidjs --template 'Hello, {{ name }}!' --context '{"name": "Snake"}'
+npx liquidjs --template 'Hello, {{ name }}!' --context '{"name": "Liquid"}'
 ```
 
-For more details, refer to the [Setup Guide][setup].
+See the [setup guide][setup] for partials, layouts, caching, and other options.
 
-## Who's Using LiquidJS?
+## Used by
 
-- [Eleventy](https://www.11ty.dev/): Eleventy, a simpler static site generator.
-- [Github Docs](https://github.com/github/docs): The open-source repo for docs.github.com.
-- [Kibana](https://github.com/elastic/kibana): Elastic's analytics and visualization platform for Elasticsearch; workflow features use LiquidJS for Liquid templates.
-- [Opensense](https://www.opensense.com/): The smarter way to send email.
-- [Directus](https://docs.directus.io/): an instant REST+GraphQL API and intuitive no-code data collaboration app for any SQL database.
-- [Rock](https://www.rockrms.com/): An open source CMS, Relationship Management System (RMS) and Church Management System (ChMS) all rolled into one.
-- [Mitosis](https://github.com/BuilderIO/mitosis): Write components once, run everywhere. Compiles to React, Vue, Qwik, Solid, Angular, Svelte, and more.
-- [Pattern Lab](https://patternlab.io/): a frontend workshop environment that helps you build, view, test, and showcase your design system's UI components.
-- [Builder.io](https://www.builder.io/m/developers): the first and only headless CMS with a visual editor that lets you drag and drop with your components, directly within your current site or app. Completely API-driven, for cleaner code and simpler workflows.
-- [Microsoft Power Pages](https://learn.microsoft.com/en-us/power-pages/introduction): a secure, enterprise-grade, low-code software as a service (SaaS) platform for creating, hosting, and administering modern external-facing business websites.
-- [Azure API Management developer portal](https://learn.microsoft.com/en-us/azure/api-management/api-management-howto-developer-portal): an automatically generated, fully customizable website with the documentation of your APIs.
-- [WISMOlabs](https://wismolabs.com/): Post Purchase Experience platform for eCommerce retailers enhancing customer satisfaction by using LiquidJS to provide customizable post-purchase experiences through programmable email, SMS, order tracking pages, and webhooks.
-- [Freshet](https://chromewebstore.google.com/detail/freshet/mpclplhdencffbilobpcapccnihpelcg): *JSON in, page out* — a Chrome extension that uses LiquidJS templates per URL pattern, so the JSON becomes a rendered, useful page.
+<!-- USED-BY-BEGIN -->
+<p align="center" style="line-height: 2.5;">
+  <a href="https://www.11ty.dev/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://avatars.githubusercontent.com/u/35147177?v=4&s=100" height="80" style="vertical-align: middle;" alt="Eleventy" title="Eleventy"/></a>
+  <a href="https://www.opensense.com/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://images.opencollective.com/opensense-inc/bf840ae/logo/256.png?height=100" height="80" style="vertical-align: middle;" alt="Opensense" title="Opensense"/></a>
+  <a href="https://www.microsoft.com/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://avatars.githubusercontent.com/u/6154722?v=4&s=100" height="80" style="vertical-align: middle;" alt="Power Pages, Azure API Management developer portal" title="Power Pages, Azure API Management developer portal"/></a>
+  <a href="https://docs.github.com/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://avatars.githubusercontent.com/u/9919?v=4&amp;s=100" height="80" style="vertical-align: middle;" alt="GitHub Docs" title="GitHub Docs"/></a>
+  <a href="https://github.com/elastic/kibana" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://avatars.githubusercontent.com/u/6764390?v=4&s=100" height="80" style="vertical-align: middle;" alt="Kibana" title="Kibana"/></a>
+  <a href="https://www.shopify.com/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://avatars.githubusercontent.com/u/8085?v=4&amp;s=100" height="80" style="vertical-align: middle;" alt="Shopify CLI, Checkout Blocks" title="Shopify CLI, Checkout Blocks"/></a>
+  <a href="https://customer.io/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://avatars.githubusercontent.com/u/1152079?v=4&s=100" height="80" style="vertical-align: middle;" alt="Customer IO" title="Customer IO"/></a>
+  <br/>
+  <a href="https://syntax.fm/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://avatars.githubusercontent.com/u/130389858?v=4&s=100" height="80" style="vertical-align: middle;" alt="Syntax Podcast" title="Syntax Podcast"/></a>
+  <a href="https://www.testmuai.com/?utm_medium=sponsor&utm_source=liquidjs" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://avatars.githubusercontent.com/u/27130435?s=200&v=4" width="80" style="vertical-align: middle;" alt="TestMu AI" title="TestMu AI"/></a>
+  <a href="https://chudovo.com/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://images.opencollective.com/Chudovo/avatar/256.png?height=100" width="160" style="vertical-align: middle;background: white;padding: 8px 16px;" alt="Chudovo" title="Chudovo"/></a>
+  <a href="https://www.pakstyle.pk/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://images.opencollective.com/pakstyle/2b81605/logo/256.png?height=100" height="80" style="vertical-align: middle;" alt="PakStyle.pk" title="PakStyle.pk"/></a>
+  <a href="https://www.escorta.com/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://images.opencollective.com/escortacom/avatar/256.png?height=100" height="45" style="vertical-align: middle;" alt="EscortA.com" title="EscortA.com"/></a>
+  <a href="https://opencollective.com/touchless" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://images.opencollective.com/touchless/273bc74/logo/256.png?height=100" height="80" style="vertical-align: middle;" alt="Touchless" title="Touchless"/></a>
+  <br/>
+  <a href="https://www.dropkiq.com/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://images.opencollective.com/1bertlol/43a8ea8/logo/256.png?height=100" height="80" style="vertical-align: middle;" alt="Dropkiq" title="Dropkiq"/></a>
+  <a href="https://directus.io/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://avatars.githubusercontent.com/u/15967950?v=4&amp;s=100" height="80" style="vertical-align: middle;" alt="Directus" title="Directus"/></a>
+  <a href="https://www.builder.io/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://cdn.builder.io/api/v1/image/assets%2FYJIGb4i01jvw0SRdL5Bt%2F51a002f4a17f4fc4a829b8891a1c25ee" height="80" style="vertical-align: middle;" alt="Builder.io, Mitosis" title="Builder.io, Mitosis"/></a>
+  <a href="https://patternlab.io/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://avatars.githubusercontent.com/u/4733935?v=4&amp;s=100" height="80" style="vertical-align: middle;" alt="Pattern Lab" title="Pattern Lab"/></a>
+  <a href="https://www.rockrms.com/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://www.rockrms.com/GetImage.ashx?id=72533" height="80" style="vertical-align: middle;" alt="Rock RMS" title="Rock RMS"/></a>
+  <a href="https://wismolabs.com/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://cdn-ldlap.nitrocdn.com/DsLJMZpUUekfsitqBnNmsRAnzbwPoIzE/assets/images/optimized/rev-5df8687/wismolabs.com/wp-content/uploads/2023/03/favicon-300x300.png" height="80" style="vertical-align: middle;" alt="WISMOlabs" title="WISMOlabs"/></a>
+  <a href="https://chromewebstore.google.com/detail/freshet/mpclplhdencffbilobpcapccnihpelcg" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://raw.githubusercontent.com/MattAltermatt/freshet/main/public/icon-128.png" height="80" style="vertical-align: middle;" alt="Freshet" title="Freshet"/></a>
+</p>
+<!-- USED-BY-END -->
 
-Feel free to create a PR or contact me to add your use case into this list!
+Products and projects running on LiquidJS. [Open a PR](https://github.com/harttle/liquidjs/edit/master/README.md) to add yours.
 
 ## Financial Support
 
@@ -78,7 +92,7 @@ If you personally love LiquidJS or it's benefiting your business, please conside
   <a href="https://www.opensense.com/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://images.opencollective.com/opensense-inc/bf840ae/logo/256.png?height=100" height="80" style="vertical-align: middle;" alt="Opensense Inc." title="Opensense"/></a>
   <a href="https://github.com/microsoft" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://avatars.githubusercontent.com/u/6154722?v=4&s=100" height="80" style="vertical-align: middle;" alt="Microsoft" title="Microsoft"/></a>
   <a href="https://sentry.io/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://avatars.githubusercontent.com/u/1396951?v=4&s=100" height="80" style="vertical-align: middle;" alt="Sentry" title="Sentry"/></a>
-  <a href="https://www.checkoutblocks.com/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://avatars.githubusercontent.com/u/114603307?v=4&s=100" height="80" style="vertical-align: middle;" alt="Checkout Blocks" title="Checkout Blocks"/></a>
+  <a href="https://github.com/Checkout-Blocks" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://avatars.githubusercontent.com/u/114603307?v=4&s=100" height="80" style="vertical-align: middle;" alt="Checkout Blocks" title="Checkout Blocks"/></a>
   <a href="https://customer.io/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://avatars.githubusercontent.com/u/1152079?v=4&s=100" height="80" style="vertical-align: middle;" alt="Customer IO" title="Customer IO"/></a>
   <a href="https://syntax.fm/" style="display: inline-block; vertical-align: middle; margin: 8px;"><img src="https://avatars.githubusercontent.com/u/130389858?v=4&s=100" height="80" style="vertical-align: middle;" alt="Syntax Podcast" title="Syntax Podcast"/></a>
   <br/>
@@ -226,6 +240,9 @@ Want to contribute? see [Contribution Guidelines][contribution]. Thanks goes to
       <td align="center" valign="top" width="14.28%"><a href="https://github.com/talboren"><img src="https://avatars.githubusercontent.com/u/68807791?v=4?s=100" width="100px;" alt="Tal"/><br /><sub><b>Tal</b></sub></a><br /><a href="https://github.com/harttle/liquidjs/commits?author=talboren" title="Code">💻</a></td>
       <td align="center" valign="top" width="14.28%"><a href="https://filonov.dev"><img src="https://avatars.githubusercontent.com/u/813224?v=4?s=100" width="100px;" alt="Vladimir Filonov"/><br /><sub><b>Vladimir Filonov</b></sub></a><br /><a href="https://github.com/harttle/liquidjs/commits?author=VladimirFilonov" title="Code">💻</a></td>
     </tr>
+    <tr>
+      <td align="center" valign="top" width="14.28%"><a href="https://github.com/spokodev"><img src="https://avatars.githubusercontent.com/u/239690017?v=4?s=100" width="100px;" alt="spokodev"/><br /><sub><b>spokodev</b></sub></a><br /><a href="https://github.com/harttle/liquidjs/commits?author=spokodev" title="Code">💻</a></td>
+    </tr>
   </tbody>
 </table>
 
@@ -234,8 +251,10 @@ Want to contribute? see [Contribution Guidelines][contribution]. Thanks goes to
 
 <!-- ALL-CONTRIBUTORS-LIST:END -->
 
-[shopify/liquid]: https://shopify.github.io/liquid/
-[plugins]: https://liquidjs.com/tutorials/plugins.html#Plugin-List
+## License
+
+[MIT](LICENSE) © [Jun Yang](https://github.com/harttle)
+
 [setup]: https://liquidjs.com/tutorials/setup.html
 [doc]: https://liquidjs.com
 [github]: https://github.com/harttle/liquidjs

SECURITY.md

@@ -6,8 +6,10 @@ Only the latest major version is supported with security updates. It can be chan
 
 ## Reporting a Vulnerability
 
-Please contact harttleharttle@gmail.com to report a vulnerability or change request.
+**Please do not report security vulnerabilities through public GitHub issues.**
 
-- If the vulnerability in question affects common use cases, it will be treated as a bug and fixed very soon (typically within 1 week).
+Report them via [GitHub Security Advisories — Report a vulnerability](https://github.com/harttle/liquidjs/security/advisories/new).
+
+- If the vulnerability in question affects common use cases, it will be treated as a bug and fixed very soon (typically within a month).
 - Otherwise, it'll be scheduled in the same priority of feature request (which is lower than bugs).
-- If the request is declined, you'll receive a reply email anyway (most likely there will be a discussion).
+- If the request is declined, you'll receive a reply anyway (most likely there will be a discussion).

bin/build-contributors.js

@@ -33,7 +33,9 @@ function transformFinancial (html) {
 
 const allContributors = transformContributors(extractSection(readme, 'ALL-CONTRIBUTORS-LIST:START', 'ALL-CONTRIBUTORS-LIST:END'))
 const financialContributors = transformFinancial(extractSection(readme, 'FINANCIAL-CONTRIBUTORS-BEGIN', 'FINANCIAL-CONTRIBUTORS-END'))
+const usedBy = transformFinancial(extractSection(readme, 'USED-BY-BEGIN', 'USED-BY-END'))
 
 const outDir = path.join(root, 'docs/themes/navy/layout/partial')
 fs.writeFileSync(path.join(outDir, 'all-contributors.swig'), allContributors)
 fs.writeFileSync(path.join(outDir, 'financial-contributors.swig'), financialContributors)
+fs.writeFileSync(path.join(outDir, 'used-by.swig'), usedBy)

demo/express/test.sh

@@ -7,13 +7,13 @@ while ! grep -q "Express running" "$LOG_FILE"; do
   if ! kill -0 $SERVER_PID; then
     echo "Server exited unexpectedly."
     cat $LOG_FILE
-    return 1
+    exit 1
   fi
   sleep 1
 done
 curl http://127.0.0.1:3000 | grep -q 'Welcome to LiquidJS'
 RESULT=$?
-killall node
+killall node || true
 rm $LOG_FILE
 if [ $RESULT != 0 ]; then
   exit 1

docs/_config.yml

@@ -1,6 +1,6 @@
 title: LiquidJS
-subtitle: "A simple, expressive, and safe template engine for JavaScript."
-description: "LiquidJS is a simple, expressive, and safe template engine for JavaScript, compatible with Shopify and GitHub Pages."
+subtitle: "A simple, expressive, extensible Liquid template engine for JavaScript"
+description: "A simple, expressive, extensible Liquid template engine for JavaScript — Shopify, Jekyll and GitHub Pages compatible, for Node.js, browsers, and the CLI, with TypeScript support."
 author: Harttle
 language: en
 timezone: UTC

docs/source/filters/strip_html.md

@@ -6,6 +6,10 @@ title: strip_html
 
 Removes any HTML tags from a string.
 
+{% note warn Not safe for HTML output %}
+This filter removes tags by string scanning; it does not parse HTML5 the way a browser does, and it is not a sanitizer. The result may still be unsafe when inserted into HTML. Use [escape][escape], [escape_once][escape_once], or [`outputEscape: "escape"`][outputEscape] for untrusted output.
+{% endnote %}
+
 Input
 ```liquid
 {{ "Have <em>you</em> read <strong>Ulysses</strong>?" | strip_html }}
@@ -15,3 +19,7 @@ Output
 ```text
 Have you read Ulysses?
 ```
+
+[escape]: ./escape.html
+[escape_once]: ./escape.html
+[outputEscape]: ../tutorials/options.html#outputEscape

docs/source/index.pug

@@ -1,6 +1,4 @@
 layout: index
-description: LiquidJS is a simple, expressive and safe Shopify / GitHub Pages compatible template engine in pure JavaScript.
-subtitle: A simple, expressive and safe template engine.
 ---
 ul#intro-feature-list
   li.intro-feature-wrap

docs/source/llms.txt

@@ -0,0 +1,28 @@
+# LiquidJS
+
+> A simple, expressive, extensible Liquid template engine for JavaScript
+
+## Tutorials
+
+- [Introduction to Liquid](https://liquidjs.com/tutorials/intro-to-liquid.html)
+- [Setup](https://liquidjs.com/tutorials/setup.html)
+- [Options](https://liquidjs.com/tutorials/options.html)
+- [Render files](https://liquidjs.com/tutorials/render-file.html)
+- [Partials and layouts](https://liquidjs.com/tutorials/partials-and-layouts.html)
+- [Express.js](https://liquidjs.com/tutorials/use-in-expressjs.html)
+- [Register filters and tags](https://liquidjs.com/tutorials/register-filters-tags.html)
+- [Plugins](https://liquidjs.com/tutorials/plugins.html)
+- [Sync and async](https://liquidjs.com/tutorials/sync-and-async.html)
+- [Operators](https://liquidjs.com/tutorials/operators.html)
+- [Truthy and falsy](https://liquidjs.com/tutorials/truthy-and-falsy.html)
+- [Security model](https://liquidjs.com/tutorials/security-model.html)
+- [Differences from Shopify Liquid](https://liquidjs.com/tutorials/differences.html)
+- [Migrate to v9](https://liquidjs.com/tutorials/migrate-to-9.html)
+- [Changelog](https://liquidjs.com/tutorials/changelog.html)
+
+## Reference
+
+- [Tags](https://liquidjs.com/tags/overview.html)
+- [Filters](https://liquidjs.com/filters/overview.html)
+- [API (TypeDoc)](https://liquidjs.com/api/)
+- [Playground](https://liquidjs.com/playground.html)

docs/source/manifest.json

@@ -1,7 +1,7 @@
 {
   "short_name": "LiquidJS",
   "name": "LiquidJS",
-  "description": "A simple, expressive and safe Shopify / GitHub Pages compatible template engine in pure JavaScript.",
+  "description": "A simple, expressive, extensible Liquid template engine for JavaScript",
   "icons": [
     {
       "src": "/icon/apple-touch-icon-57x57.png",

docs/source/tutorials/intro-to-liquid.md

@@ -3,9 +3,9 @@ title: The Liquid Template Language
 describe: A short introduction to the Liquid template language and some simple demos.
 ---
 
-LiquidJS is a simple, expressive and safe [Shopify][shopify/liquid] / GitHub Pages compatible template engine in pure JavaScript. The purpose of this repo is to provide a standard Liquid implementation for the JavaScript community. Liquid is originally implemented in Ruby and used by GitHub Pages, Jekyll and Shopify, see [Differences with Shopify/liquid][diff].
+Liquid is a template language originally implemented in Ruby and used by Shopify, Jekyll, and GitHub Pages. LiquidJS implements it in JavaScript; see [Differences with Shopify/liquid][diff] for compatibility notes.
 
-LiquidJS syntax is relatively simple. There are 2 types of markups in LiquidJS:
+There are 2 types of markups in LiquidJS:
 
 - **Tags**. A tag consists of a tag name and optional arguments wrapped between `{%raw%}{%{%endraw%}` and `%}`.
 - **Outputs**. An output consists of a value and a list of filters, which is optional, wrapped between `{%raw%}{{{%endraw%}` and `}}`.
@@ -56,5 +56,4 @@ Typically tags appear in pairs with a start tag and a corresponding end tag. For
 
 A complete list of tags supported by LiquidJS can be found [here](../tags/overview.html).
 
-[shopify/liquid]: https://github.com/Shopify/liquid
 [diff]: ./differences.html

docs/source/tutorials/options.md

@@ -138,7 +138,7 @@ It defaults to `false`. For example, when set to `true`, a blank string would ev
 
 **lenientIf** modifies the behavior of `strictVariables` to allow handling optional variables. If set to `true`, an undefined variable will *not* cause an exception in the following two situations: a) it is the condition to an `if`, `elsif`, or `unless` tag; b) it occurs right before a `default` filter. Irrelevant if `strictVariables` is not set. Defaults to `false`.
 
-**ownPropertyOnly** hides scope variables from prototypes, useful when you're passing a not sanitized object into LiquidJS or need to hide prototypes from templates. Defaults to `true`.
+**ownPropertyOnly** limits template property reads on plain scope objects to own properties. Defaults to `true`. See [Security Model](./security-model.html).
 
 {% note info Nonexistent Tags %}
 Nonexistent tags always throw errors during parsing and this behavior cannot be customized.

docs/source/tutorials/render-tag-content.md

@@ -22,7 +22,7 @@ Expected output:
 </div>
 ```
 
-Firstly, [register][register-tags] a tag named `wrap` and parse the content into `this.tpls`. Here in `parse(tagToken, remainTokens)`:
+Firstly, [register][register-tags] a tag named `wrap` and parse the content into `this.tpls`. In the tag `constructor(tagToken, remainTokens, liquid)`:
 
 - `tagToken` is current token `{%raw%}{% wrap %}{%endraw%}`, and
 - `remainTokens` is an array of all tokens following `{%raw%}{% wrap %}{%endraw%}` until the end of this template file.
@@ -30,11 +30,14 @@ Firstly, [register][register-tags] a tag named `wrap` and parse the content into
 Basically, what we need to do is take/`.shift()` enough tags from `remainTokens` until we get an `endwrap` token (the name can be arbitrary, but by convention it should be `endwrap`). And if there's no `endwrap` until the end of the template file, we need to throw a tag-not-closed `Error`.
 
 ```javascript
-engine.registerTag('wrap', {
-  parse(tagToken, remainTokens) {
-    this.tpls = []
+const { Tag } = require('liquidjs')
+
+engine.registerTag('wrap', class WrapTag extends Tag {
+  tpls = []
+  constructor(tagToken, remainTokens, liquid) {
+    super(tagToken, remainTokens, liquid)
     let closed = false
-    while(remainTokens.length) {
+    while (remainTokens.length) {
       let token = remainTokens.shift()
       // we got the end tag! stop taking tokens
       if (token.name === 'endwrap') {
@@ -44,11 +47,11 @@ engine.registerTag('wrap', {
       // parse token into template
       // parseToken() may consume more than 1 tokens
       // e.g. {% if %}...{% endif %}
-      let tpl = this.liquid.parser.parseToken(token, remainTokens)
+      let tpl = liquid.parser.parseToken(token, remainTokens)
       this.tpls.push(tpl)
     }
     if (!closed) throw new Error(`tag ${tagToken.getText()} not closed`)
-  },
+  }
   * render(context, emitter) {
     emitter.write("<div class='wrapper'>")
     yield this.liquid.renderer.renderTemplates(this.tpls, context, emitter)
@@ -57,16 +60,17 @@ engine.registerTag('wrap', {
 })
 ```
 
-`.renderTemplates()` can be async; we need `yield` to wait for it to complete. For more details on async in LiquidJS, see [Sync and Async][async]. Other parts of the `render()` method are quite straightforward. Here's a JSFiddle version: <https://jsfiddle.net/por0zcn1/3/>
+`.renderTemplates()` can be async; we need `yield` to wait for it to complete. For more details on async in LiquidJS, see [Sync and Async][async]. Here's a JSFiddle version: <https://jsfiddle.net/por0zcn1/3/>
 
 ## Using ParseStream
 
-When it comes to complex tags like [for][for] and [if][if], the `parse()` can be very complicated. There's a [ParseStream][ParseStream] utility to organize the `parse()` in event-based style. Following is a re-written `parse()` using `ParseStream` that does exactly the same as the example above.
+For more complex tags such as [for][for] and [if][if], constructor parsing can get unwieldy. [ParseStream][ParseStream] offers an event-based API for this. The constructor below is equivalent to the example above:
 
 ```javascript
-parse(tagToken, remainTokens) {
-  this.tpls = []
-  this.liquid.parser.parseStream(remainTokens)
+tpls = []
+constructor(tagToken, remainTokens, liquid) {
+  super(tagToken, remainTokens, liquid)
+  liquid.parser.parseStream(remainTokens)
     .on('template', tpl => this.tpls.push(tpl))
     // note that we cannot use arrow function because we need `this`
     .on('tag:endwrap', function () { this.stop() })
@@ -103,15 +107,18 @@ As you've noticed, there's an additional `repeat.i` in the context of `repeat`.
 Each time we enter a new *Context*, we need to push a new *Scope*. And when we finish rendering and exit the *Context*, we pop the *Scope* from the *Context*. As you can see in the following implementation:
 
 ```javascript
-engine.registerTag('repeat', {
-  parse(tagToken, remainTokens) {
-    this.tpls = []
-    this.liquid.parser.parseStream(remainTokens)
+const { Tag } = require('liquidjs')
+
+engine.registerTag('repeat', class RepeatTag extends Tag {
+  tpls = []
+  constructor(tagToken, remainTokens, liquid) {
+    super(tagToken, remainTokens, liquid)
+    liquid.parser.parseStream(remainTokens)
       .on('template', tpl => this.tpls.push(tpl))
       .on('tag:endrepeat', function () { this.stop() })
       .on('end', () => { throw new Error(`tag ${tagToken.getText()} not closed`) })
       .start()
-  },
+  }
   * render(context, emitter) {
     const repeat = { i: 1 }
     context.push({ repeat })
@@ -123,7 +130,7 @@ engine.registerTag('repeat', {
 })
 ```
 
-The `parse()` is exactly the same as `wrap` tag, we repeat the content simply by calling `.renderTemplates(this.tpls)` twice during `render()`. Here's the JSFiddle: <https://jsfiddle.net/por0zcn1/2/>
+The constructor is the same as in the `wrap` tag; we repeat the content by calling `.renderTemplates(this.tpls)` twice during `render()`. Here's the JSFiddle: <https://jsfiddle.net/por0zcn1/2/>
 
 {% note warn Use Push & Pop in Pairs %}
 `context.push()` and `context.pop()` have to be used in pairs. Failing to `pop()` the *Scope* you pushed will leak the *Scope* to latter templates and may corrupt the *Context* stack.

docs/source/tutorials/security-model.md

@@ -2,21 +2,19 @@
 title: Security Model
 ---
 
-LiquidJS provides DoS-oriented limits (`parseLimit`, `renderLimit`, `memoryLimit`) to reduce risk. This page summarizes those limits, [`ownPropertyOnly`][ownPropertyOnly], custom [`Drop`][drop] usage, and the security boundary to assume in production.
+LiquidJS provides DoS-oriented limits (`parseLimit`, `templateLimit`, `outputLengthLimit`, `maxDepth`) to reduce risk. This page summarizes those limits, [`ownPropertyOnly`][ownPropertyOnly], custom [`Drop`][drop] usage, and the security boundary to assume in production.
 
-## Security boundary
+## At a glance
 
-The built-in limits are cooperative safeguards, not strict runtime isolation.
-
-- They do **not** equal process RSS/heap usage.
-- They do **not** sandbox JavaScript execution.
-- They should be combined with process/container limits and request timeouts for defense in depth.
-
-## Limits at a glance
+LiquidJS ships a thin cooperative DoS layer:
 
 - [parseLimit][parseLimit]: limit total template size per `parse()` call.
-- [renderLimit][renderLimit]: limit total render time per `render()` call.
-- [memoryLimit][memoryLimit]: cooperatively limit memory-sensitive allocations counted by LiquidJS.
+- [templateLimit][templateLimit]: limit total tag/HTML/output nodes rendered per `render()` call.
+- [outputLengthLimit][outputLengthLimit]: limit total output length per `render()` call.
+- [maxDepth][maxDepth]: limit nesting depth of `{% render %}`, `{% include %}`, and `{% layout %}`.
+- Strftime numeric pad widths in the `date` filter are capped at `1_000_000` (1M) per conversion.
+
+These are cooperative safeguards, not runtime isolation—see [Production guidance](#production-guidance) below for host-level limits and online-service hardening.
 
 ## Limit details
 
@@ -26,9 +24,9 @@ The built-in limits are cooperative safeguards, not strict runtime isolation.
 
 A typical PC handles `1e8` (100M) characters without issues.
 
-### renderLimit
+### templateLimit
 
-Restricting template size alone is insufficient because dynamic loops with large counts can occur during rendering. [renderLimit][renderLimit] mitigates this by limiting the time consumed by each `render()` call.
+Restricting template size alone is insufficient because dynamic loops with large counts can occur during rendering. [templateLimit][templateLimit] mitigates this by limiting the number of tag, HTML literal, and output nodes rendered in each `render()` call.
 
 ```liquid
 {%- for i in (1..10000000) -%}
@@ -36,52 +34,47 @@ Restricting template size alone is insufficient because dynamic loops with large
 {%- endfor -%}
 ```
 
-Render time is checked on a per-template basis (before rendering each template). In the above example, there are 2 templates in the loop: `order: ` and `{{i}}`, render time will be checked 10000000x2 times.
+Each template node (the `for` tag, literal `order: `, output `{{i}}`, and so on) counts toward the limit. In the above example, a limit of `30000000` would be exceeded before the loop finishes.
 
-`renderLimit` is not a hard CPU limiter. It is checked between template renders, so compute-intensive filters/tags/user-defined functions or deeply nested template execution between checks can still cause DoS.
+`templateLimit` is checked before each node render, so compute-intensive filters/tags/user-defined functions between checks can still cause DoS.
 
-### memoryLimit
+### outputLengthLimit
 
-`memoryLimit` only limits operations that LiquidJS explicitly counts.
+[outputLengthLimit][outputLengthLimit] caps the cumulative length of output written during a `render()` call, including output from partials rendered via `{% render %}`.
 
-- Counted: memory-sensitive LiquidJS operations that call internal memory accounting.
-- Not guaranteed counted: arbitrary user object behavior such as custom `toValue()`/`toString()` chains, or other host-side code that allocates outside LiquidJS accounting points.
+### maxDepth
 
-In other words, `memoryLimit` limits what LiquidJS counts, not every byte your process may allocate.
+[maxDepth][maxDepth] limits how deeply `{% render %}`, `{% include %}`, and `{% layout %}` can nest. Defaults to `128`. In sync rendering (`renderSync`), nested tags are driven by `toValueSync`, which recursively resumes each yielded generator on the call stack—deep nesting can overflow it, and `maxDepth` caps that depth. Async `render()` resumes the same tag generators via `toPromise`/`yield` without a deep synchronous call chain, so stack overflow is not a concern there (the limit still applies as a DoS guard).
 
-Even with a small number of templates and iterations, memory usage can grow exponentially. In the following example, memory doubles with each iteration:
-
-```liquid
-{% assign array = "1,2,3" | split: "," %}
-{% for i in (1..32) %}
-    {% assign array = array | concat: array %}
-{% endfor %}
-```
-
-As [JavaScript uses GC to manage memory](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Memory_management), `memoryLimit` may not reflect the actual memory footprint.
+The `memoryLimit` option was removed in v11; enforce memory limits at the host or process level instead.
 
 ## `ownPropertyOnly` and scope data
 
-With [`ownPropertyOnly`][ownPropertyOnly] `true`, plain scope objects only expose **own** properties (no inherited / `Object.prototype` keys). Default `false` follows normal JS property access. Use `true` for untrusted or polluted objects; add [`strictVariables`][strictVariables] if missing paths should error. Override per render via [`RenderOptions`][renderOwnPropertyOnly]. This is a read policy for scope data—not a sandbox for filters, tags, or your code.
+With [`ownPropertyOnly`][ownPropertyOnly] `true` (default), plain scope objects only expose **own** properties (no inherited / `Object.prototype` keys), and reads of `__proto__`, `constructor`, and `prototype` are blocked (own and inherited) as a prototype-pollution defense. With `false`, inherited properties and those keys are allowed—sanitize untrusted scope data (e.g. with [bourne](https://www.npmjs.com/package/bourne)) before passing it as scope. LiquidJS also uses null-prototype objects for managed scope frames (e.g. `{% capture %}`, `{% assign %}`) so internal frames do not inherit from `Object.prototype`.
+
+Not restricted: [`Drop`][drop] values, iteration via `Symbol.iterator`, `.size`/`.first`/`.last`, filters, and custom tags.
+
+Use `true` for untrusted objects; add [`strictVariables`][strictVariables] if missing paths should error. Override per render via [`RenderOptions`][renderOwnPropertyOnly]. This is a read policy for scope data—not a sandbox for filters, tags, or your code.
 
 ## Custom `Drop` classes
 
 [`Drop`][drop] values are not restricted the same way: LiquidJS still reads the prototype chain and may call [`liquidMethodMissing`][liquidMethodMissing]. **You** control what a drop exposes; narrow APIs and never feed unsafe data into drops unless the class is built for template access. `ownPropertyOnly` alone does not harden custom drops—audit them like any privileged code.
 
-## Online service guidance
+## Production guidance
 
-If you run an online service, avoid rendering fully user-defined templates whenever possible.
+LiquidJS does not sandbox template code—custom filters, tags, and scope helpers run as ordinary JavaScript with your process privileges. Built-in DoS limits are one layer; production deployments, especially online services that accept template input, need additional hardening:
 
-- Prefer curated templates or a restricted template subset.
-- If user-defined templates are required, isolate rendering (worker/process/container), enforce OS/container memory and CPU limits, and apply request rate limits.
-- Treat `parseLimit`/`renderLimit`/`memoryLimit` as one layer in a broader DoS defense strategy.
-
-For heavy single-template operations, process-level isolation is still recommended (for example with [paralleljs][paralleljs]).
+- **Prefer curated templates** over fully user-defined Liquid when possible; if users need customization, offer a restricted subset rather than open template editing.
+- Run each render in a **worker thread or child process** with a wall-clock timeout; **kill** the worker on expiry. Libraries such as [paralleljs][paralleljs] can help for heavy single-template work.
+- Enforce **container/Kubernetes cgroup limits**, `ulimit`, or equivalent on the renderer process for memory and CPU.
+- Apply **request rate limits** at the API or gateway layer.
+- **`node:vm`, `isolated-vm`, and Jinja/Twig-style sandbox modes are not a security boundary**—template logic runs in the same JS runtime as your app, with your privileges.
 
 [paralleljs]: https://www.npmjs.com/package/paralleljs
 [parseLimit]: /api/interfaces/LiquidOptions.html#parseLimit
-[renderLimit]: /api/interfaces/LiquidOptions.html#renderLimit
-[memoryLimit]: /api/interfaces/LiquidOptions.html#memoryLimit
+[templateLimit]: /api/interfaces/LiquidOptions.html#templateLimit
+[outputLengthLimit]: /api/interfaces/LiquidOptions.html#outputLengthLimit
+[maxDepth]: /api/interfaces/LiquidOptions.html#maxDepth
 [ownPropertyOnly]: /api/interfaces/LiquidOptions.html#ownPropertyOnly
 [renderOwnPropertyOnly]: /api/interfaces/RenderOptions.html#ownPropertyOnly
 [strictVariables]: /api/interfaces/LiquidOptions.html#strictVariables

docs/themes/navy/languages/en.yml

@@ -13,10 +13,14 @@ index:
     description: 'Thanks to these wonderful people! See <a href="tutorials/contribution-guidelines.html">contribution guidelines</a> if you&#39;d like to help.'
   sponsors:
     title: Sponsors
-    description: 'If you personally love LiquidJS or it&#39;s benefiting your business, please <a href="https://github.com/sponsors/harttle">sponsor us</a>!'
+    description: 'Organizations and individuals who <a href="https://github.com/sponsors/harttle">sponsor LiquidJS</a>. Thank you!'
+  used_by:
+    title: Used by
+    description: 'Products and projects running on LiquidJS. <a href="https://github.com/harttle/liquidjs/edit/master/README.md">Open a PR</a> to add yours.'
 
 playground:
   title: Playground
+  lead: Edit a template and context JSON — rendered HTML updates as you type.
   loading: Loading...
 
 page:

docs/themes/navy/layout/index.swig

@@ -1,6 +1,6 @@
 <header id="banner" class="wrapper">
   <div class="inner inner-content">
-    <h2 id="banner-title">{{ page.subtitle }}</h2>
+    <h2 id="banner-title">{{ page.subtitle | default(config.subtitle) }}</h2>
     <div id="banner-share">{{ partial('partial/share') }}</div>
     <div id="banner-start">
       <code id="banner-start-command">npm install liquidjs</code><a id="banner-start-link" href="./tutorials/setup.html"><i class="icon-arrow-right"></i></a>
@@ -14,15 +14,15 @@
     </div>
   </div>
 </div>
-<div id="contributors-wrap">
+<div id="used-by-wrap">
   <div class="wrapper">
     <div class="inner inner-content">
       <div class="section-header">
-        <h3>{{__('index.contributors.title')}}</h3>
-        <p class="description">{{__('index.contributors.description')}}</p>
+        <h3>{{__('index.used_by.title')}}</h3>
+        <p class="description">{{__('index.used_by.description')}}</p>
       </div>
       <div class="contributors">
-        {{ partial('partial/all-contributors') }}
+        {{ partial('partial/used-by') }}
       </div>
     </div>
   </div>
@@ -40,3 +40,16 @@
     </div>
   </div>
 </div>
+<div id="contributors-wrap">
+  <div class="wrapper">
+    <div class="inner inner-content">
+      <div class="section-header">
+        <h3>{{__('index.contributors.title')}}</h3>
+        <p class="description">{{__('index.contributors.description')}}</p>
+      </div>
+      <div class="contributors">
+        {{ partial('partial/all-contributors') }}
+      </div>
+    </div>
+  </div>
+</div>

docs/themes/navy/layout/partial/after_footer.swig

@@ -1,6 +1,11 @@
 {% if page.layout === 'playground' %}
 {{ js('js/liquid.browser.min.js') }}
 <script src="https://cdn.jsdelivr.net/npm/[email protected]/src-min/ace.js"></script>
+<script src="https://cdn.jsdelivr.net/npm/[email protected]/src-min/mode-liquid.js"></script>
+<script src="https://cdn.jsdelivr.net/npm/[email protected]/src-min/mode-json.js"></script>
+<script>ace.config.set('basePath', 'https://cdn.jsdelivr.net/npm/[email protected]/src-min/');</script>
+<script src="https://cdn.jsdelivr.net/npm/[email protected]/prism.min.js"></script>
+<script src="https://cdn.jsdelivr.net/npm/[email protected]/components/prism-markup.min.js"></script>
 {% endif %}
 
 {{ js('js/main') }}
@@ -17,12 +22,10 @@ debug: false
 });
 </script>
 
-<!-- Google tag (gtag.js) -->
 <script async src="https://www.googletagmanager.com/gtag/js?id=G-GM713991QQ"></script>
-<script>
+<script type="text/plain" data-category="analytics">
   window.dataLayer = window.dataLayer || [];
   function gtag(){dataLayer.push(arguments);}
   gtag('js', new Date());
-
   gtag('config', 'G-GM713991QQ');
 </script>

docs/themes/navy/layout/partial/demo.json

@@ -1,7 +1,3 @@
 {
-  "people": [
-    "alice",
-    "bob",
-    "carol"
-  ]
+  "name": "liquid"
 }

docs/themes/navy/layout/partial/demo.liquid

@@ -1,9 +1 @@
-<ul>
-{%- for person in people %}
-  <li>
-    <a href="{{person | prepend: "https://example.com/"}}">
-      {{ person | capitalize }}
-    </a>
-  </li>
-{%- endfor%}
-</ul>
+<p>Hello, {{ name | capitalize }}!</p>

docs/themes/navy/layout/partial/footer.swig

@@ -5,6 +5,7 @@
       {{__('footer.license')}}
     </div>
     <div id="footer-links">
+      <button type="button" class="footer-link cookie-preferences" data-cc="show-consentModal" title="Manage cookie preferences"><i class="icon-shield"></i></button>
       <a href="https://twitter.com/{{ config.twitter }}" class="footer-link" target="_blank"><i class="icon-twitter"></i></a>
       <a href="https://opencollective.com/{{ config.oc }}" class="footer-link" target="_blank"><i class="icon-opencollective"></i></a>
       <a href="https://github.com/{{ config.github }}" class="footer-link" target="_blank"><i class="icon-github"></i></a>

docs/themes/navy/layout/partial/head.swig

@@ -32,12 +32,7 @@
   <meta name="msapplication-TileImage" content="{{ url_for('icon/mstile-144x144.png') }}">
   {{ css('css/navy') }}
   {{ feed_tag('atom.xml') }}
-  <script src="https://cdn.cookiehub.eu/c2/e8e44c93.js"></script>
-  <script type="text/javascript">
-  document.addEventListener("DOMContentLoaded", function(event) {
-    if (location.hostname === 'localhost' || location.hostname === '127.0.0.1') return;
-    var cpm = {};
-    window.cookiehub.load(cpm);
-  });
-  </script>
+  <link rel="stylesheet" href="https://cdn.jsdelivr.net/gh/orestbida/[email protected]/dist/cookieconsent.css">
+  <script src="https://cdn.jsdelivr.net/gh/orestbida/[email protected]/dist/cookieconsent.umd.js"></script>
+  {{ js('js/cookieconsent-config') }}
 </head>

docs/themes/navy/layout/playground.swig

@@ -1,21 +1,45 @@
 <div id="playground" role="main">
   <div class="wrapper">
-    <h1 class="inner">{{__('playground.title')}}</h1>
+    <header class="playground-hero inner">
+      <div class="playground-hero-text">
+        <h1>{{__('playground.title')}}</h1>
+        <p class="playground-lead">{{__('playground.lead')}}</p>
+      </div>
+      <p class="playground-version version"></p>
+    </header>
     <div class="loader" role=status aria-busy=true></div>
     <div id="editors" class="inner hide" aria-hide=true>
-      <div class="area-tpl editor-wrapper">
-        <h2>Template</h2>
-        <div class="editor" id="editorEl">{{ raw('partial/demo.liquid') }}</div>
-      </div>
-      <div class="area-data editor-wrapper">
-        <h2>Context</h2>
-        <div class="editor" id="dataEl">{{ raw('partial/demo.json') }}</div>
-      </div>
-      <div class="area-output editor-wrapper">
-        <h2>Output</h2>
-        <div class="editor" id="previewEl">{{__('playground.loading')}}</div>
+      <div class="playground-workspace">
+        <div class="playground-pane area-tpl">
+          <div class="pane-head">
+            <span class="pane-indicator" data-state="idle" aria-hidden="true"></span>
+            <h2>Template</h2>
+          </div>
+          <div class="pane-body">
+            <div class="editor" id="editorEl">{{ raw('partial/demo.liquid') }}</div>
+          </div>
+        </div>
+        <div class="playground-pane area-data">
+          <div class="pane-head">
+            <span class="pane-indicator" data-state="idle" aria-hidden="true"></span>
+            <h2>Context</h2>
+          </div>
+          <div class="pane-body">
+            <div class="editor" id="dataEl">{{ raw('partial/demo.json') }}</div>
+          </div>
+        </div>
+        <div class="playground-pane area-output">
+          <div class="pane-head">
+            <span class="pane-indicator" data-state="idle" aria-hidden="true"></span>
+            <h2>Output</h2>
+          </div>
+          <div class="pane-body">
+            <div class="output-preview" id="previewEl">
+              <pre class="highlight"><code class="language-markup" id="previewCode">{{__('playground.loading')}}</code></pre>
+            </div>
+          </div>
+        </div>
       </div>
     </div>
-    <p class="inner version"></p>
   </div>
 </div>

docs/themes/navy/source/css/_partial/cookieconsent.styl

@@ -0,0 +1,15 @@
+#cc-main
+  --cc-btn-primary-bg: var(--color-link)
+  --cc-btn-primary-color: #fff
+  --cc-btn-primary-border-color: var(--color-link)
+  --cc-btn-primary-hover-bg: var(--color-link-hover)
+  --cc-btn-primary-hover-border-color: var(--color-link-hover)
+  --cc-btn-secondary-bg: #eaeff2
+  --cc-btn-secondary-color: var(--color-default)
+  --cc-btn-secondary-border-color: #eaeff2
+  --cc-toggle-on-bg: var(--color-link)
+
+.cc--darkmode #cc-main
+  --cc-btn-secondary-bg: #3a4248
+  --cc-btn-secondary-color: var(--color-default)
+  --cc-btn-secondary-border-color: #3a4248

docs/themes/navy/source/css/_partial/footer.styl

@@ -42,6 +42,13 @@
   @media mq-normal
     font-size: 30px
 
+.cookie-preferences
+  background: none
+  border: 0
+  padding: 0
+  cursor: pointer
+  color: inherit
+
 .icon-oc
   height: 36px
   width: 30px

docs/themes/navy/source/css/_partial/index.styl

@@ -126,7 +126,7 @@
     background: var(--color-link-hover)
     color: #fff
 
-#sponsors-wrap, #contributors-wrap
+#used-by-wrap, #sponsors-wrap, #contributors-wrap
   background: var(--color-navy-lighter)
   border-top: 1px solid #161d24
   border-bottom: 1px solid #161d24
@@ -181,7 +181,7 @@
 
 #contributors-wrap
   border: none
-  overflow: hidden;
+  overflow: hidden
 
 .contributors
   tr

docs/themes/navy/source/css/_partial/playground.styl

@@ -1,107 +1,312 @@
 #playground
+  --playground-gap: 12px
+  --playground-radius: 10px
+  --playground-inset: 16px
   background: var(--color-content-bg)
   overflow: hidden
   box-shadow: var(--panel-shadow)
 
   .wrapper
-    margin-bottom: 40px
+    margin-bottom: 32px
+    @media mq-mobile
+      margin-bottom: 20px
+
+  .playground-hero
+    display: flex
+    flex-wrap: wrap
+    align-items: flex-end
+    justify-content: space-between
+    gap: 16px 24px
+    padding-top: 32px
+    padding-bottom: 20px
+    @media mq-mobile
+      padding-top: 16px
+      padding-bottom: 12px
+      gap: 10px
+      align-items: flex-start
+
+  .playground-hero-text
+    flex: 1 1 280px
+    min-width: 0
 
   h1
-    font-size: 36px
-    font-weight: 300
-    margin-top: 40px
-    margin-bottom: 24px
-    color: var(--color-default)
-
-  h2
-    font-size: 0.8125rem
+    font-size: 28px
     font-weight: 600
-    text-transform: uppercase
-    letter-spacing: 0.04em
-    color: var(--color-gray)
+    letter-spacing: -0.02em
+    margin: 0 0 8px
+    color: var(--color-default)
+    @media mq-mobile
+      font-size: 22px
+      margin-bottom: 4px
+
+  .playground-lead
     margin: 0
+    font-size: 15px
+    line-height: 1.5
+    color: var(--color-gray)
+    @media mq-mobile
+      font-size: 14px
+      line-height: 1.45
+
+  .playground-version
+    flex: 0 0 auto
+    margin: 0
+    font-size: 12px
+    line-height: 1.4
+    font-family: font-mono
+    padding: 6px 12px
+    border-radius: 999px
+    background: var(--playground-surface)
+    border: 1px solid var(--color-border)
+    color: var(--color-gray)
+    a
+      color: var(--color-default)
+      text-decoration: none
+      font-weight: 500
+      &:hover
+        color: var(--color-link)
+        text-decoration: none
 
   #editors
-    display: grid
-    overflow: hidden
     margin-bottom: 0
-    height: 75vh
-    min-height: 480px
+
+  .playground-workspace
+    display: grid
+    gap: var(--playground-gap)
     grid-template-columns: 1fr 1fr
     grid-template-rows: 3fr 2fr
-    grid-gap: 16px
     align-items: stretch
+    @media mq-normal
+      overflow: hidden
+      height: 75vh
+      max-height: unquote('calc(100vh - 200px)')
+      min-height: 520px
     @media mq-mobile
-      height: auto
-      min-height: 0
       grid-template-columns: 1fr
       grid-template-rows: auto
-      grid-gap: 20px
+      gap: 12px
 
   .area-tpl
     grid-row: 1
     grid-column: 1
     min-height: 0
+    --pane-dot: var(--color-link)
   .area-data
     grid-row: 2
     grid-column: 1
     min-height: 0
+    --pane-dot: var(--highlight-orange)
   .area-output
     grid-column: 2
     grid-row: 1 / -1
     min-height: 0
+    min-width: 0
+    --pane-dot: var(--highlight-green)
     @media mq-mobile
       grid-row: auto
       grid-column: 1
 
-  .editor-wrapper
+  .playground-pane
     display: flex
-    gap: 8px
     flex-direction: column
     min-height: 0
     overflow: hidden
-    .editor
-      flex: 1 1 auto
-      min-height: 0
-      position: relative
-      code-block-chrome()
-      overflow: hidden
-      @media mq-mobile
-        min-height: 240px
-    .ace_editor
-      font-family: font-mono
-      font-size: 14px
-      line-height: 1.5
-      border-radius: 6px
-    .ace_scrollbar
-      z-index: 2
+    background: var(--playground-pane-head)
+    border: 1px solid var(--code-border)
+    border-radius: var(--playground-radius)
+    box-shadow: var(--code-shadow)
 
-  .version
-    font-size: 0.8125rem
-    line-height: 1.5
+  .pane-head
+    display: flex
+    align-items: center
+    gap: 10px
+    flex-shrink: 0
+    height: 36px
+    padding: 0 var(--playground-inset)
+    border-bottom: 1px solid var(--code-border)
+    @media mq-mobile
+      height: 32px
+      padding: 0 10px
+    h2
+      font-size: 13px
+      font-weight: 600
+      letter-spacing: 0.01em
+      text-transform: none
+      color: var(--color-default)
+      margin: 0
+      @media mq-mobile
+        font-size: 12px
+
+  .pane-indicator
+    width: 8px
+    height: 8px
+    border-radius: 50%
+    flex-shrink: 0
+    background: unquote('color-mix(in srgb, var(--pane-dot) 38%, var(--color-border))')
+    transition: background 0.25s ease, box-shadow 0.25s ease, transform 0.25s ease
+
+    &[data-state="active"]
+      background: var(--pane-dot)
+      animation: playground-dot-typing 0.85s ease-in-out infinite
+
+    &[data-state="pending"]
+      background: var(--highlight-yellow)
+
+    &[data-state="ok"]
+      background: var(--highlight-green)
+      animation: playground-dot-ok 0.45s ease-out
+
+    &[data-state="error"]
+      background: var(--highlight-red)
+      animation: playground-dot-error 0.35s ease-out
+
+  .area-output .pane-indicator
+    &[data-state="pending"]
+      animation: playground-dot-pending 0.55s ease-in-out infinite
+
+  @keyframes playground-dot-typing
+    0%, 100%
+      transform: scale(1)
+      box-shadow: 0 0 0 0 unquote('color-mix(in srgb, var(--pane-dot) 0%, transparent)')
+    50%
+      transform: scale(1.2)
+      box-shadow: 0 0 0 4px unquote('color-mix(in srgb, var(--pane-dot) 28%, transparent)')
+
+  @keyframes playground-dot-pending
+    0%, 100%
+      transform: scale(1)
+      opacity: 0.75
+    50%
+      transform: scale(1.12)
+      opacity: 1
+
+  @keyframes playground-dot-ok
+    0%
+      transform: scale(0.85)
+      box-shadow: 0 0 0 0 unquote('color-mix(in srgb, var(--highlight-green) 50%, transparent)')
+    70%
+      transform: scale(1.15)
+      box-shadow: 0 0 0 5px unquote('color-mix(in srgb, var(--highlight-green) 0%, transparent)')
+    100%
+      transform: scale(1)
+      box-shadow: none
+
+  @keyframes playground-dot-error
+    0%, 100%
+      transform: translateX(0)
+    20%
+      transform: translateX(-2px)
+    40%
+      transform: translateX(2px)
+    60%
+      transform: translateX(-1px)
+    80%
+      transform: translateX(1px)
+
+  .pane-body
+    flex: 1 1 auto
+    min-height: 0
+    min-width: 0
+    display: flex
+    flex-direction: column
+    overflow: hidden
+    background: var(--highlight-background)
+
+  .area-tpl .pane-body,
+  .area-data .pane-body
+    padding: var(--playground-inset)
+    box-sizing: border-box
+    @media mq-mobile
+      padding: 12px
+
+  .area-tpl .ace_gutter,
+  .area-data .ace_gutter
+    display: none
+    width: 0
+    min-width: 0
+
+  .area-tpl .ace_editor,
+  .area-data .ace_editor,
+  .area-tpl .ace_scroller,
+  .area-data .ace_scroller,
+  .area-tpl .ace_content,
+  .area-data .ace_content,
+  .area-tpl .ace_text-layer,
+  .area-data .ace_text-layer
+    background: transparent
+
+  .editor
+    flex: 1 1 auto
+    min-height: 0
+    position: relative
+    overflow: hidden
+    @media mq-mobile
+      min-height: 180px
+
+  .output-preview
+    flex: 1 1 auto
+    min-height: 0
+    min-width: 0
+    width: 100%
+    overflow: auto
+    @media mq-mobile
+      min-height: 120px
+    pre.highlight
+      margin: 0
+      min-height: 100%
+      width: 100%
+      box-sizing: border-box
+      padding: var(--playground-inset)
+      border: none
+      box-shadow: none
+      border-radius: 0
+      background: transparent
+      color: var(--highlight-foreground)
+      overflow-x: hidden
+      overflow-y: auto
+      white-space: pre-wrap
+      overflow-wrap: break-word
+      @media mq-mobile
+        padding: 12px
+      code
+        display: block
+        width: 100%
+        box-sizing: border-box
+        font-family: font-mono
+        font-size: 14px
+        line-height: 1.55
+        color: var(--highlight-foreground)
+        background: transparent
+        padding: 0
+        white-space: inherit
+        overflow-wrap: inherit
+        @media mq-mobile
+          font-size: 13px
+
+  .ace_editor
     font-family: font-mono
-    color: var(--color-gray)
-    margin-top: 20px
-    margin-bottom: 32px
-    a
-      color: inherit
-      text-decoration: none
-      &:hover
-        color: var(--color-link)
-        text-decoration: underline
+    font-size: 14px
+    line-height: 1.55
+    border-radius: 0
+    @media mq-mobile
+      font-size: 13px
+  .ace_scrollbar
+    z-index: 2
 
   .hide
     display: none
 
   .loader
-    width: 48px
-    height: 48px
-    margin: 150px auto 200px
-    border: 3px solid var(--color-border)
+    width: 40px
+    height: 40px
+    margin: 120px auto 160px
+    border: 2px solid var(--color-border)
     border-top-color: var(--color-link)
     border-radius: 50%
-    animation: spin 0.8s infinite linear
+    animation: playground-spin 0.7s infinite linear
+    @media mq-mobile
+      margin: 60px auto 80px
 
-  @keyframes spin
+  @keyframes playground-spin
     100%
       transform: rotate(360deg)

docs/themes/navy/source/css/_variables.styl

@@ -37,6 +37,8 @@ vendor-prefixes = webkit moz ms official
     --highlight-aqua: #0550ae
     --highlight-blue: #0550ae
     --highlight-purple: #8250df
+    --playground-surface: #f3f4f6
+    --playground-pane-head: #fff
 }
 
 @media (prefers-color-scheme: dark) {
@@ -75,6 +77,8 @@ vendor-prefixes = webkit moz ms official
         --highlight-aqua: #79c0ff
         --highlight-blue: #79c0ff
         --highlight-purple: #d2a8ff
+        --playground-surface: hsl(218, 26%, 10%)
+        --playground-pane-head: hsl(218, 22%, 16%)
     }
 }
 

docs/themes/navy/source/css/navy.styl

@@ -9,6 +9,7 @@
 @import "_partial/page"
 @import "_partial/mobile_nav"
 @import "_partial/footer"
+@import "_partial/cookieconsent"
 @import "_partial/highlight"
 @import "_partial/icomoon.css"
 @import "_partial/docsearch.min.css"

docs/themes/navy/source/js/cookieconsent-config.js

@@ -0,0 +1,49 @@
+(function () {
+  if (window.matchMedia('(prefers-color-scheme: dark)').matches) {
+    document.documentElement.classList.add('cc--darkmode');
+  }
+
+  var config = {
+    guiOptions: {
+      consentModal: {
+        equalWeightButtons: false
+      }
+    },
+    categories: {
+      necessary: {
+        enabled: true,
+        readOnly: true
+      },
+      analytics: {
+        enabled: false
+      }
+    },
+    language: {
+      default: 'en',
+      translations: {
+        en: {
+          consentModal: {
+            title: 'We use cookies',
+            description: 'This site uses cookies for analytics and to improve your experience.',
+            acceptAllBtn: 'Accept',
+            acceptNecessaryBtn: 'Reject'
+          }
+        }
+      }
+    }
+  };
+
+  if (/^localhost$|^127\.0\.0\.1$/i.test(location.hostname)) {
+    config.cookie = { secure: false };
+  }
+
+  function run() {
+    CookieConsent.run(config);
+  }
+
+  if (document.readyState === 'loading') {
+    document.addEventListener('DOMContentLoaded', run);
+  } else {
+    run();
+  }
+}());

docs/themes/navy/source/js/main.js

@@ -38,24 +38,28 @@
 
 (function() {
   // playground
-  /* global liquidjs, ace */
-  if (!location.pathname.match(/playground.html$/)) return;
+  /* global liquidjs, ace, Prism */
+  if (!/\/playground(?:\.html)?$/.test(location.pathname)) return;
   updateVersion(liquidjs.version);
   const engine = new liquidjs.Liquid({
-    memoryLimit: 1e5,
-    renderLimit: 1e5
+    templateLimit: 1e5
   });
   const colorScheme = window.matchMedia('(prefers-color-scheme: dark)');
   const editor = createEditor('editorEl', 'liquid');
   const dataEditor = createEditor('dataEl', 'json');
-  const preview = createEditor('previewEl', 'html');
-  preview.setReadOnly(true);
-  preview.renderer.setShowGutter(false);
-  preview.renderer.setPadding(16);
+  const previewCode = document.getElementById('previewCode');
+  const indicatorTpl = document.querySelector('.area-tpl .pane-indicator');
+  const indicatorData = document.querySelector('.area-data .pane-indicator');
+  const indicatorOutput = document.querySelector('.area-output .pane-indicator');
 
-  const editors = [editor, dataEditor, preview];
+  const editors = [editor, dataEditor];
+  let previewValue = '';
+  let hadPreview = false;
+  let renderTimer = null;
+  const RENDER_DELAY = 180;
   colorScheme.addEventListener('change', function() {
     editors.forEach(applyEditorTheme);
+    if (previewValue) setPreview(previewValue);
   });
 
   const init = parseArgs(location.hash.slice(1));
@@ -63,9 +67,11 @@
     editor.setValue(init.tpl, 1);
     dataEditor.setValue(init.data, 1);
   }
-  editor.on('change', update);
-  dataEditor.on('change', update);
-  update();
+  editor.on('change', onTemplateChange);
+  dataEditor.on('change', onContextChange);
+  editor.on('focus', function () { setIndicator(indicatorTpl, 'active'); });
+  dataEditor.on('focus', function () { setIndicator(indicatorData, 'active'); });
+  scheduleUpdate();
   ready();
 
   function ready() {
@@ -87,6 +93,8 @@
 
   function applyEditorTheme(editor) {
     editor.setTheme(getEditorTheme());
+    editor.renderer.setPadding(0);
+    editor.container.style.background = 'transparent';
   }
 
   function createEditor(id, lang) {
@@ -96,15 +104,61 @@
       fontFamily: '"Source Code Pro", ui-monospace, Monaco, Menlo, Consolas, monospace',
       fontSize: '14px',
       showPrintMargin: false,
+      showGutter: false,
+      highlightActiveLine: false,
       tabSize: 2,
       useSoftTabs: true,
-      scrollPastEnd: 0.25
+      scrollPastEnd: 0
     });
     editor.getSession().setMode('ace/mode/' + lang);
-    editor.renderer.setScrollMargin(8, 8, 0, 0);
+    editor.renderer.setShowGutter(false);
+    if (editor.renderer.$gutter) {
+      editor.renderer.$gutter.style.display = 'none';
+    }
+    editor.renderer.setScrollMargin(0, 0, 0, 0);
+    bindClipboard(editor);
     return editor;
   }
 
+  function bindClipboard(editor) {
+    editor.commands.addCommand({
+      name: 'copy',
+      bindKey: {win: 'Ctrl-C', mac: 'Command-C'},
+      exec: function (ed) {
+        const text = ed.getCopyText();
+        if (!text) return;
+        if (navigator.clipboard && window.isSecureContext) {
+          navigator.clipboard.writeText(text);
+        }
+      },
+      readOnly: true
+    });
+    editor.commands.addCommand({
+      name: 'cut',
+      bindKey: {win: 'Ctrl-X', mac: 'Command-X'},
+      exec: function (ed) {
+        const text = ed.getCopyText();
+        if (!text) return;
+        if (navigator.clipboard && window.isSecureContext) {
+          navigator.clipboard.writeText(text).then(function () {
+            ed.insert('');
+          });
+        }
+      }
+    });
+    editor.commands.addCommand({
+      name: 'paste',
+      bindKey: {win: 'Ctrl-V', mac: 'Command-V'},
+      exec: function (ed) {
+        if (navigator.clipboard && window.isSecureContext) {
+          navigator.clipboard.readText().then(function (text) {
+            ed.insert(text);
+          });
+        }
+      }
+    });
+  }
+
   function parseArgs(hash) {
     if (!hash) return;
     try {
@@ -118,16 +172,64 @@
     return utoa(obj.tpl) + ',' + utoa(obj.data);
   }
 
+  function setPreview(value) {
+    previewValue = value;
+    previewCode.textContent = value;
+    if (window.Prism) {
+      delete previewCode.dataset.highlighted;
+      window.Prism.highlightElement(previewCode);
+    }
+  }
+
+  function setIndicator(indicator, state) {
+    if (indicator) indicator.dataset.state = state;
+  }
+
+  function onTemplateChange() {
+    setIndicator(indicatorTpl, 'active');
+    if (indicatorData.dataset.state !== 'error') setIndicator(indicatorData, 'idle');
+    setIndicator(indicatorOutput, 'pending');
+    scheduleUpdate();
+  }
+
+  function onContextChange() {
+    setIndicator(indicatorData, 'active');
+    if (indicatorTpl.dataset.state !== 'error') setIndicator(indicatorTpl, 'idle');
+    setIndicator(indicatorOutput, 'pending');
+    scheduleUpdate();
+  }
+
+  function scheduleUpdate() {
+    clearTimeout(renderTimer);
+    renderTimer = setTimeout(update, RENDER_DELAY);
+  }
+
   async function update() {
     const tpl = editor.getValue();
     const data = dataEditor.getValue();
     history.replaceState({}, '', '#' + serializeArgs({tpl, data}));
+    let parsed;
     try {
-      const html = await engine.parseAndRender(tpl, JSON.parse(data));
-      preview.setValue(html, 1);
+      parsed = JSON.parse(data);
     } catch (err) {
-      preview.setValue(err.stack, 1);
-      throw err;
+      setIndicator(indicatorData, 'error');
+      setIndicator(indicatorTpl, 'idle');
+      setIndicator(indicatorOutput, 'error');
+      return;
+    }
+    try {
+      const html = await engine.parseAndRender(tpl, parsed);
+      if (html !== '' || !hadPreview) {
+        setPreview(html);
+        if (html !== '') hadPreview = true;
+      }
+      setIndicator(indicatorTpl, 'idle');
+      setIndicator(indicatorData, 'idle');
+      setIndicator(indicatorOutput, 'ok');
+    } catch (err) {
+      setIndicator(indicatorTpl, 'error');
+      setIndicator(indicatorData, 'idle');
+      setIndicator(indicatorOutput, 'error');
     }
   }
 

package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "liquidjs",
-  "version": "10.27.0",
+  "version": "10.27.1",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "liquidjs",
-      "version": "10.27.0",
+      "version": "10.27.1",
       "license": "MIT",
       "dependencies": {
         "commander": "^10.0.0"
@@ -64,7 +64,7 @@
         "typescript": "^4.5.3"
       },
       "engines": {
-        "node": ">=16"
+        "node": ">=20"
       },
       "funding": {
         "type": "opencollective",

package.json

@@ -1,8 +1,8 @@
 {
   "name": "liquidjs",
-  "version": "10.27.0",
+  "version": "10.27.1",
   "sideEffects": false,
-  "description": "A simple, expressive and safe Shopify / Github Pages compatible template engine in pure JavaScript.",
+  "description": "A simple, expressive, extensible Liquid template engine for JavaScript — Shopify, Jekyll and GitHub Pages compatible, for Node.js, browsers, and the CLI, with TypeScript support.",
   "main": "dist/liquid.node.js",
   "module": "dist/liquid.node.mjs",
   "es2015": "dist/liquid.browser.mjs",
@@ -12,7 +12,7 @@
   },
   "types": "dist/index.d.ts",
   "engines": {
-    "node": ">=16"
+    "node": ">=20"
   },
   "scripts": {
     "lint": "eslint \"**/*.mjs\" \"**/*.ts\" .",
@@ -29,12 +29,15 @@
     "build:min": "BUNDLES=min rollup -c rollup.config.mjs",
     "build:umd": "BUNDLES=umd rollup -c rollup.config.mjs",
     "build:charmap": "./bin/character-gen.js > src/util/character.ts",
-    "build:docs": "run-s build:docs-liquid build:contributors build:apidoc build:changelog build:docs-hexo",
+    "prepare:docs": "run-s build:docs-liquid build:contributors build:apidoc build:changelog",
+    "build:docs": "run-s prepare:docs build:docs-hexo",
     "build:docs-liquid": "cross-env BUNDLES=min rollup -c rollup.config.mjs && shx cp dist/liquid.browser.min.js docs/themes/navy/source/js/",
     "build:contributors": "node bin/build-contributors.js",
     "build:apidoc": "shx rm -rf docs/source/api && typedoc --plugin typedoc-plugin-missing-exports ./src --gitRevision master --out docs/source/api",
     "build:changelog": "node bin/build-changelog.js",
-    "build:docs-hexo": "cd docs && npm ci && npm run build && shx cp CNAME public/"
+    "build:docs-hexo": "cd docs && npm ci && npm run build && shx cp CNAME public/",
+    "serve:docs": "cd docs && npm run start",
+    "dev:docs": "run-s prepare:docs serve:docs"
   },
   "bin": {
     "liquidjs": "./bin/liquid.js",
@@ -118,45 +121,6 @@
   "dependencies": {
     "commander": "^10.0.0"
   },
-  "release": {
-    "branch": "master",
-    "plugins": [
-      "@semantic-release/commit-analyzer",
-      "@semantic-release/release-notes-generator",
-      "@semantic-release/changelog",
-      "@semantic-release/npm",
-      [
-        "@semantic-release/git",
-        {
-          "assets": [
-            "package.json",
-            "package-lock.json",
-            "CHANGELOG.md"
-          ],
-          "message": "chore(release): ${nextRelease.version} [skip ci]\n\n${nextRelease.notes}"
-        }
-      ],
-      [
-        "@semantic-release/github",
-        {
-          "assets": [
-            {
-              "path": "dist/*.umd.js",
-              "label": "liquid.js"
-            },
-            {
-              "path": "dist/*.min.js",
-              "label": "liquid.min.js"
-            },
-            {
-              "path": "dist/*.min.js.map",
-              "label": "liquid.min.js.map"
-            }
-          ]
-        }
-      ]
-    ]
-  },
   "publishConfig": {
     "provenance": true
   },

rollup.config.mjs

@@ -23,8 +23,7 @@ const tsconfig = (target) => ({
     compilerOptions: {
       target,
       module: 'ES2015',
-      rootDir: 'src',
-      downlevelIteration: true
+      rootDir: 'src'
     }
   }
 })
@@ -89,7 +88,7 @@ const nodeEsm = {
   plugins: [
     versionInjection,
     replace(esmRequire),
-    typescript(tsconfig('es6'))
+    typescript(tsconfig('ES2020'))
   ],
   treeshake,
   input
@@ -108,7 +107,7 @@ const browserEsm = {
     replace(browserBase64),
     replace(browserCrypto),
     replace(browserStream),
-    typescript(tsconfig('es6'))
+    typescript(tsconfig('ES2020'))
   ],
   treeshake,
   input
@@ -128,7 +127,7 @@ const browserUmd = {
     replace(browserBase64),
     replace(browserCrypto),
     replace(browserStream),
-    typescript(tsconfig('es5'))
+    typescript(tsconfig('ES2020'))
   ],
   treeshake,
   input
@@ -148,7 +147,7 @@ const browserMin = {
     replace(browserBase64),
     replace(browserCrypto),
     replace(browserStream),
-    typescript(tsconfig('es5')),
+    typescript(tsconfig('ES2020')),
     uglify()
   ],
   treeshake,

src/build/base64-impl-browser.spec.ts

@@ -2,11 +2,6 @@ import * as base64 from './base64-impl-browser'
 import { JSDOM } from 'jsdom'
 
 describe('base64-impl/browser', function () {
-  if (+(process.version.match(/^v(\d+)/) as RegExpMatchArray)[1] < 8) {
-    console.info('jsdom not supported, skipping base64-impl-browser...')
-    return
-  }
-
   beforeEach(function () {
     const dom = new JSDOM(``, {
       url: 'https://example.com/',

src/build/fs-impl-browser.spec.ts

@@ -3,10 +3,6 @@ import * as sinon from 'sinon'
 import { JSDOM } from 'jsdom'
 
 describe('fs/browser', function () {
-  if (+(process.version.match(/^v(\d+)/) as RegExpMatchArray)[1] < 8) {
-    console.info('jsdom not supported, skipping template-browser...')
-    return
-  }
   beforeEach(function () {
     const dom = new JSDOM(``, {
       url: 'https://example.com/foo/bar/',

src/context/context.spec.ts

@@ -58,6 +58,9 @@ describe('Context', function () {
     it('should return map size as size', async function () {
       expect(ctx.get(['map', 'size'])).toEqual(1)
     })
+    it('should return own size property', async function () {
+      expect(ctx.get(['zoo', 'size'])).toEqual(4)
+    })
     it('should return undefined if not have a size', async function () {
       expect(ctx.get(['one', 'size'])).toBeUndefined()
       expect(ctx.get(['non-exist', 'size'])).toBeUndefined()
@@ -130,6 +133,10 @@ describe('Context', function () {
       ctx = new Context({ foo: Object.create({ bar: 'BAR' }) }, { ownPropertyOnly: false } as any)
       return expect(ctx.getSync(['foo', 'bar'])).toEqual('BAR')
     })
+    it('should read inherited size when ownPropertyOnly=false', function () {
+      ctx = new Context({ foo: Object.create({ size: 99 }) }, { ownPropertyOnly: false } as any)
+      return expect(ctx.getSync(['foo', 'size'])).toEqual(99)
+    })
     it('renderOptions.ownPropertyOnly should override options.ownPropertyOnly', function () {
       ctx = new Context({ foo: Object.create({ bar: 'BAR' }) }, { ownPropertyOnly: false } as any, { ownPropertyOnly: true })
       return expect(ctx.getSync(['foo', 'bar'])).toEqual(undefined)
@@ -183,6 +190,51 @@ describe('Context', function () {
       ctx.push({ foo: Object.create({ bar: 'BAR' }) })
       return expect(() => ctx.getSync(['foo', 'bar'])).toThrow(/undefined variable: foo.bar/)
     })
+    it('should return undefined for inherited array indices', function () {
+      // eslint-disable-next-line no-extend-native
+      Array.prototype[0] = 'POLLUTED'
+      try {
+        const a: number[] = []
+        a.length = 1
+        ctx.push({ foo: a })
+        expect(ctx.getSync(['foo', 0])).toEqual(undefined)
+        expect(ctx.getSync(['foo', -1])).toEqual(undefined)
+        expect(ctx.getSync(['foo', 'first'])).toEqual(undefined)
+        expect(ctx.getSync(['foo', 'last'])).toEqual(undefined)
+      } finally {
+        delete (Array.prototype as any)[0]
+      }
+    })
+    it('should allow own blocked keys when ownPropertyOnly=false', function () {
+      ctx = new Context({
+        foo: {
+          ...JSON.parse('{"__proto__": {"bar": "BAR"}}'),
+          constructor: { name: 'Custom' },
+          prototype: { x: 1 }
+        }
+      }, { ownPropertyOnly: false } as any)
+      expect(ctx.getSync(['foo', '__proto__', 'bar'])).toEqual('BAR')
+      expect(ctx.getSync(['foo', 'constructor', 'name'])).toEqual('Custom')
+      expect(ctx.getSync(['foo', 'prototype', 'x'])).toEqual(1)
+    })
+    it('should allow inherited properties when ownPropertyOnly=false', function () {
+      ctx = new Context({ foo: Object.create({ __proto__: { bar: 'BAR' }, constructor: { name: 'Evil' } }) }, { ownPropertyOnly: false } as any)
+      expect(ctx.getSync(['foo', '__proto__', '__proto__', 'bar'])).toEqual('BAR')
+      expect(ctx.getSync(['foo', 'constructor', 'name'])).toEqual('Evil')
+    })
+    it('should block own constructor when ownPropertyOnly=true', function () {
+      ctx.push({ foo: { constructor: { name: 'Evil' } } })
+      expect(ctx.getSync(['foo', 'constructor'])).toEqual(undefined)
+    })
+    it('should block own prototype when ownPropertyOnly=true', function () {
+      ctx.push({ foo: { prototype: { bar: 'BAR' } } })
+      expect(ctx.getSync(['foo', 'prototype'])).toEqual(undefined)
+    })
+    it('should block own top-level __proto__ variable when ownPropertyOnly=true', function () {
+      ctx = new Context(JSON.parse('{"__proto__": {"bar": "BAR"}, "bar": "BAR"}'))
+      expect(ctx.getSync(['__proto__'])).toEqual(undefined)
+      expect(ctx.getSync(['bar'])).toEqual('BAR')
+    })
   })
 
   describe('.getAll()', function () {
@@ -206,6 +258,11 @@ describe('Context', function () {
       expect(ctx.getSync(['bar', 'foo'])).toEqual('foo')
       expect(ctx.getSync(['bar', 'bar'])).toEqual(undefined)
     })
+    it('should return pushed scope for in-place mutation', function () {
+      const scope = ctx.push({})
+      scope.item = 'ITEM'
+      expect(ctx.getSync(['item'])).toEqual('ITEM')
+    })
   })
   describe('.pop()', function () {
     it('should pop scope', async function () {

src/context/context.ts

@@ -1,12 +1,13 @@
-import { getPerformance } from '../util/performance'
 import { Drop } from '../drop/drop'
 import { __assign } from 'tslib'
 import { NormalizedFullOptions, defaultOptions, RenderOptions } from '../liquid-options'
 import { createScope, Scope } from './scope'
-import { hasOwnProperty, isArray, isNil, isUndefined, isString, isFunction, toLiquid, InternalUndefinedVariableError, toValueSync, isObject, Limiter, toValue } from '../util'
+import { hasOwnProperty, isArray, isNil, isUndefined, isString, isFunction, isNumber, toLiquid, InternalUndefinedVariableError, toValueSync, isObject, Limiter, toValue, readArrayElement } from '../util'
 
 type PropertyKey = string | number;
 
+const BLOCKED_SCOPE_KEYS: ReadonlySet<PropertyKey> = new Set(['__proto__', 'constructor', 'prototype'])
+
 export class Context {
   /**
    * insert a Context-level empty scope,
@@ -36,17 +37,19 @@ export class Context {
    */
   public strictVariables: boolean;
   public ownPropertyOnly: boolean;
-  public memoryLimit: Limiter;
-  public renderLimit: Limiter;
-  public constructor (env: object = {}, opts: NormalizedFullOptions = defaultOptions, renderOptions: RenderOptions = {}, { memoryLimit, renderLimit }: { [key: string]: Limiter } = {}) {
+  public templateLimit: Limiter;
+  public outputLengthLimit: Limiter;
+  public depthLimit: Limiter;
+  public constructor (env: object = {}, opts: NormalizedFullOptions = defaultOptions, renderOptions: RenderOptions = {}, { templateLimit, outputLengthLimit, depthLimit }: { templateLimit?: Limiter, outputLengthLimit?: Limiter, depthLimit?: Limiter } = {}) {
     this.sync = !!renderOptions.sync
     this.opts = opts
     this.globals = renderOptions.globals ?? opts.globals
     this.environments = isObject(env) ? env : Object(env)
     this.strictVariables = renderOptions.strictVariables ?? this.opts.strictVariables
     this.ownPropertyOnly = renderOptions.ownPropertyOnly ?? opts.ownPropertyOnly
-    this.memoryLimit = memoryLimit ?? new Limiter('memory alloc', renderOptions.memoryLimit ?? opts.memoryLimit)
-    this.renderLimit = renderLimit ?? new Limiter('template render', getPerformance().now() + (renderOptions.renderLimit ?? opts.renderLimit))
+    this.templateLimit = templateLimit ?? new Limiter('template', renderOptions.templateLimit ?? opts.templateLimit)
+    this.outputLengthLimit = outputLengthLimit ?? new Limiter('output length', renderOptions.outputLengthLimit ?? opts.outputLengthLimit)
+    this.depthLimit = depthLimit ?? new Limiter('template depth', opts.maxDepth)
   }
   public getRegister<T> (key: string, defaultValue: T = undefined as T): T {
     return (this.registers[key] = this.registers[key] || defaultValue)
@@ -93,8 +96,10 @@ export class Context {
     }
     return scope
   }
-  public push (ctx: object) {
-    return this.scopes.push(ctx)
+  public push (ctx: Scope): Scope {
+    const scope = createScope(ctx)
+    this.scopes.push(scope)
+    return scope
   }
   public pop () {
     return this.scopes.pop()
@@ -109,50 +114,51 @@ export class Context {
       strictVariables: this.strictVariables,
       ownPropertyOnly: this.ownPropertyOnly
     }, {
-      renderLimit: this.renderLimit,
-      memoryLimit: this.memoryLimit
+      templateLimit: this.templateLimit,
+      outputLengthLimit: this.outputLengthLimit,
+      depthLimit: this.depthLimit
     })
   }
   private findScope (key: string | number) {
     for (let i = this.scopes.length - 1; i >= 0; i--) {
       const candidate = this.scopes[i]
-      if (key in candidate) return candidate
+      if (this.ownPropertyOnly ? hasOwnProperty.call(candidate, key) : key in candidate) return candidate
     }
-    if (key in this.environments) return this.environments
+    if (this.ownPropertyOnly ? hasOwnProperty.call(this.environments, key) : key in this.environments) return this.environments
     return this.globals
   }
   readProperty (obj: Scope, key: (PropertyKey | Drop)) {
     obj = toLiquid(obj)
     key = toValue(key) as PropertyKey
     if (isNil(obj)) return obj
-    if (isArray(obj) && (key as number) < 0) return obj[obj.length + +key]
+    if (isArray(obj) && isNumber(key)) return readArrayElement(obj, key, this.ownPropertyOnly)
     const value = readJSProperty(obj, key, this.ownPropertyOnly)
     if (value === undefined && obj instanceof Drop) return obj.liquidMethodMissing(key, this)
     if (isFunction(value)) return value.call(obj)
-    if (key === 'size') return readSize(obj)
-    else if (key === 'first') return readFirst(obj)
-    else if (key === 'last') return readLast(obj)
+    if (key === 'size') return this.readSize(obj)
+    else if (key === 'first') return this.readFirst(obj)
+    else if (key === 'last') return this.readLast(obj)
     return value
   }
+  private readFirst (obj: Scope) {
+    if (isArray(obj)) return readArrayElement(obj, 0, this.ownPropertyOnly)
+    return readJSProperty(obj, 'first', this.ownPropertyOnly)
+  }
+  private readLast (obj: Scope) {
+    if (isArray(obj)) return readArrayElement(obj, -1, this.ownPropertyOnly)
+    return readJSProperty(obj, 'last', this.ownPropertyOnly)
+  }
+  private readSize (obj: Scope) {
+    if (hasOwnProperty.call(obj, 'size')) return obj['size']
+    if (!this.ownPropertyOnly && obj['size'] !== undefined) return obj['size']
+    if (isArray(obj) || isString(obj)) return obj.length
+    if (obj instanceof Map || obj instanceof Set) return obj.size
+    if (typeof obj === 'object') return Object.keys(obj).length
+  }
 }
 
 export function readJSProperty (obj: Scope, key: PropertyKey, ownPropertyOnly: boolean) {
+  if (BLOCKED_SCOPE_KEYS.has(key) && ownPropertyOnly) return undefined
   if (ownPropertyOnly && !hasOwnProperty.call(obj, key) && !(obj instanceof Drop)) return undefined
   return obj[key]
 }
-
-function readFirst (obj: Scope) {
-  if (isArray(obj)) return obj[0]
-  return obj['first']
-}
-
-function readLast (obj: Scope) {
-  if (isArray(obj)) return obj[obj.length - 1]
-  return obj['last']
-}
-
-function readSize (obj: Scope) {
-  if (hasOwnProperty.call(obj, 'size') || obj['size'] !== undefined) return obj['size']
-  if (isArray(obj) || isString(obj)) return obj.length
-  if (typeof obj === 'object') return Object.keys(obj).length
-}

src/context/scope.ts

@@ -6,8 +6,7 @@ export interface ScopeObject extends Record<string | number | symbol, any> {
 
 export type Scope = ScopeObject | Drop
 
-export function createScope (from?: ScopeObject): ScopeObject {
-  const scope = Object.create(null)
-  if (from) Object.assign(scope, from)
-  return scope
+export function createScope (from?: Scope): Scope {
+  if (from instanceof Drop) return from
+  return Object.assign(Object.create(null), from)
 }

src/emitters/index.ts

@@ -1,4 +1,3 @@
 export * from './emitter'
 export * from './simple-emitter'
 export * from './streamed-emitter'
-export * from './keeping-type-emitter'

src/emitters/keeping-type-emitter.ts

@@ -1,19 +0,0 @@
-import { stringify, toValue } from '../util'
-import { Emitter } from './emitter'
-
-export class KeepingTypeEmitter implements Emitter {
-  public buffer: any = '';
-
-  public write (html: any) {
-    html = toValue(html)
-    // This will only preserve the type if the value is isolated.
-    // I.E:
-    // {{ my-port }} -> 42
-    // {{ my-host }}:{{ my-port }} -> 'host:42'
-    if (typeof html !== 'string' && this.buffer === '') {
-      this.buffer = html
-    } else {
-      this.buffer = stringify(this.buffer) + stringify(html)
-    }
-  }
-}

src/emitters/simple-emitter.ts

@@ -1,10 +1,17 @@
-import { stringify } from '../util'
+import { stringify, Limiter } from '../util'
 import { Emitter } from './emitter'
 
 export class SimpleEmitter implements Emitter {
   public buffer = '';
+  private outputLengthLimit?: Limiter
+
+  constructor (outputLengthLimit?: Limiter) {
+    this.outputLengthLimit = outputLengthLimit
+  }
 
   public write (html: any) {
-    this.buffer += stringify(html)
+    const str = stringify(html)
+    this.outputLengthLimit?.use(str.length)
+    this.buffer += str
   }
 }

src/emitters/streamed-emitter.ts

@@ -1,12 +1,20 @@
-import { stringify } from '../util'
+import { stringify, Limiter } from '../util'
 import { Emitter } from './emitter'
 import { PassThrough } from 'stream'
 
 export class StreamedEmitter implements Emitter {
   public buffer = '';
   public stream: NodeJS.ReadWriteStream = new PassThrough()
+  private outputLengthLimit?: Limiter
+
+  constructor (outputLengthLimit?: Limiter) {
+    this.outputLengthLimit = outputLengthLimit
+  }
+
   public write (html: any) {
-    this.stream.write(stringify(html))
+    const str = stringify(html)
+    this.outputLengthLimit?.use(str.length)
+    this.stream.write(str)
   }
   public error (err: Error) {
     this.stream.emit('error', err)

src/filters/array.ts

@@ -1,4 +1,4 @@
-import { toArray, argumentsToValue, toValue, stringify, caseInsensitiveCompare, orderedCompare, isArray, isNil, last as arrayLast, isArrayLike, toEnumerable } from '../util'
+import { toArray, argumentsToValue, toValue, stringify, caseInsensitiveCompare, orderedCompare, isArray, isNil, isArrayLike, readArrayElement, toEnumerable } from '../util'
 import { arrayIncludes, equals, evalToken, isTruthy } from '../render'
 import { Value, FilterImpl } from '../template'
 import { Tokenizer } from '../parser'
@@ -8,22 +8,22 @@ import { EmptyDrop } from '../drop'
 export const join = argumentsToValue(function (this: FilterImpl, v: any[], arg: string) {
   const array = toArray(v)
   const sep = isNil(arg) ? ' ' : stringify(arg)
-  const complexity = array.length * (1 + sep.length)
-  this.context.memoryLimit.use(complexity)
-  return array.join(sep)
+  return Array.prototype.join.call(array, sep)
+})
+export const last = argumentsToValue(function (this: FilterImpl, v: any) {
+  return isArrayLike(v) ? readArrayElement(v, -1, this.context.ownPropertyOnly) : ''
+})
+export const first = argumentsToValue(function (this: FilterImpl, v: any) {
+  return isArrayLike(v) ? readArrayElement(v, 0, this.context.ownPropertyOnly) : ''
 })
-export const last = argumentsToValue((v: any) => isArrayLike(v) ? arrayLast(v) : '')
-export const first = argumentsToValue((v: any) => isArrayLike(v) ? v[0] : '')
 export const reverse = argumentsToValue(function (this: FilterImpl, v: any[]) {
   const array = toArray(v)
-  this.context.memoryLimit.use(array.length)
   return [...array].reverse()
 })
 
 function * sortBy<T> (this: FilterImpl, arr: T[], property: string | undefined, comparator: (a: unknown, b: unknown) => number): IterableIterator<unknown> {
   const values: [T, unknown][] = []
   const array = toArray(arr)
-  this.context.memoryLimit.use(array.length)
   for (const item of array) {
     values.push([
       item,
@@ -41,12 +41,11 @@ export function * sort_natural<T> (this: FilterImpl, arr: T[], property?: string
   return yield * sortBy.call(this, arr, property, caseInsensitiveCompare)
 }
 
-export const size = (v: string | any[]) => (v && v.length) || 0
+export const size = (v: string | any[]) => v?.length || 0
 
 export function * map (this: FilterImpl, arr: Scope[], property: string): IterableIterator<unknown> {
   const results = []
   const array = toArray(arr)
-  this.context.memoryLimit.use(array.length)
   for (const item of array) {
     results.push(yield this.context._getFromScope(item, stringify(property), false))
   }
@@ -65,15 +64,13 @@ export function * sum (this: FilterImpl, arr: Scope[], property?: string): Itera
 
 export function compact<T> (this: FilterImpl, arr: T[]) {
   const array = toArray(arr)
-  this.context.memoryLimit.use(array.length)
-  return array.filter(x => !isNil(toValue(x)))
+  return Array.prototype.filter.call(array, x => !isNil(toValue(x)))
 }
 
 export function concat<T1, T2> (this: FilterImpl, v: T1[], arg: T2[] = []): (T1 | T2)[] {
   const lhs = toArray(v)
   const rhs = toArray(arg)
-  this.context.memoryLimit.use(lhs.length + rhs.length)
-  return lhs.concat(rhs)
+  return Array.prototype.concat.call(lhs, rhs)
 }
 
 export function push<T> (this: FilterImpl, v: T[], arg: T): T[] {
@@ -82,7 +79,6 @@ export function push<T> (this: FilterImpl, v: T[], arg: T): T[] {
 
 export function unshift<T> (this: FilterImpl, v: T[], arg: T): T[] {
   const array = toArray(v)
-  this.context.memoryLimit.use(array.length)
   const clone = [...array]
   clone.unshift(arg)
   return clone
@@ -90,7 +86,6 @@ export function unshift<T> (this: FilterImpl, v: T[], arg: T): T[] {
 
 export function pop<T> (this: FilterImpl, v: T[]): T[] {
   const array = toArray(v)
-  this.context.memoryLimit.use(array.length)
   const clone = [...array]
   clone.pop()
   return clone
@@ -98,7 +93,6 @@ export function pop<T> (this: FilterImpl, v: T[]): T[] {
 
 export function shift<T> (this: FilterImpl, v: T[]): T[] {
   const array = toArray(v)
-  this.context.memoryLimit.use(array.length)
   const clone = [...array]
   clone.shift()
   return clone
@@ -109,8 +103,9 @@ export function slice<T> (this: FilterImpl, v: T[] | string, begin: number, leng
   if (isNil(v)) return []
   if (!isArray(v)) v = stringify(v)
   begin = begin < 0 ? v.length + begin : begin
-  this.context.memoryLimit.use(length)
-  return v.slice(begin, begin + length)
+  return isArray(v)
+    ? Array.prototype.slice.call(v, begin, begin + length)
+    : String.prototype.slice.call(v, begin, begin + length)
 }
 
 function expectedMatcher (this: FilterImpl, expected: any): (v: any) => boolean {
@@ -126,20 +121,18 @@ function expectedMatcher (this: FilterImpl, expected: any): (v: any) => boolean
 function * filter<T extends object> (this: FilterImpl, include: boolean, arr: T[], property: string, expected: any): IterableIterator<unknown> {
   const values: unknown[] = []
   arr = toArray(arr)
-  this.context.memoryLimit.use(arr.length)
   const token = new Tokenizer(stringify(property)).readScopeValue()
   for (const item of arr) {
     values.push(yield evalToken(token, this.context.spawn(item)))
   }
   const matcher = expectedMatcher.call(this, expected)
-  return arr.filter((_, i) => matcher(values[i]) === include)
+  return Array.prototype.filter.call(arr, (_, i) => matcher(values[i]) === include)
 }
 
 function * filter_exp<T extends object> (this: FilterImpl, include: boolean, arr: T[], itemName: string, exp: string): IterableIterator<unknown> {
   const filtered: unknown[] = []
   const keyTemplate = new Value(stringify(exp), this.liquid)
   const array = toArray(arr)
-  this.context.memoryLimit.use(array.length)
   for (const item of array) {
     this.context.push({ [itemName]: item })
     const value = yield keyTemplate.value(this.context)
@@ -169,7 +162,6 @@ export function * group_by<T extends object> (this: FilterImpl, arr: T[], proper
   const map = new Map()
   arr = toEnumerable(arr)
   const token = new Tokenizer(stringify(property)).readScopeValue()
-  this.context.memoryLimit.use(arr.length)
   for (const item of arr) {
     const key = yield evalToken(token, this.context.spawn(item))
     if (!map.has(key)) map.set(key, [])
@@ -182,7 +174,6 @@ export function * group_by_exp<T extends object> (this: FilterImpl, arr: T[], it
   const map = new Map()
   const keyTemplate = new Value(stringify(exp), this.liquid)
   arr = toEnumerable(arr)
-  this.context.memoryLimit.use(arr.length)
   for (const item of arr) {
     this.context.push({ [itemName]: item })
     const key = yield keyTemplate.value(this.context)
@@ -246,7 +237,6 @@ export function * find_exp<T extends object> (this: FilterImpl, arr: T[], itemNa
 
 export function uniq<T> (this: FilterImpl, arr: T[]): T[] {
   arr = toArray(arr)
-  this.context.memoryLimit.use(arr.length)
   return [...new Set(arr)]
 }
 
@@ -254,7 +244,6 @@ export function sample<T> (this: FilterImpl, v: T[] | string, count = 1): T | st
   v = toValue(v)
   if (isNil(v)) return []
   if (!isArray(v)) v = stringify(v)
-  this.context.memoryLimit.use(v.length)
   const shuffled = [...v].sort(() => Math.random() - 0.5)
   if (count === 1) return shuffled[0]
   return shuffled.slice(0, count)

src/filters/base64.ts

@@ -10,16 +10,13 @@ import { base64Encode, base64Decode } from './base64-impl'
 
 export function base64_encode (this: FilterImpl, value: string | Buffer): string {
   if (typeof Buffer !== 'undefined' && Buffer.isBuffer(value)) {
-    this.context.memoryLimit.use(value.byteLength)
     return value.toString('base64')
   }
   const str = stringify(value)
-  this.context.memoryLimit.use(str.length)
   return base64Encode(str)
 }
 
 export function base64_decode (this: FilterImpl, value: string): string {
   const str = stringify(value)
-  this.context.memoryLimit.use(str.length)
   return base64Decode(str)
 }

src/filters/crypto.ts

@@ -10,13 +10,11 @@ import { sha256 as sha256Impl, hmacSha256 as hmacSha256Impl } from './crypto-imp
 
 export function sha256 (this: FilterImpl, value: unknown): string | Promise<string> {
   const str = stringify(value)
-  this.context.memoryLimit.use(str.length)
   return sha256Impl(str)
 }
 
 export function hmac_sha256 (this: FilterImpl, value: unknown, key: unknown): string | Promise<string> {
   const str = stringify(value)
   const keyStr = stringify(key)
-  this.context.memoryLimit.use(str.length + keyStr.length)
   return hmacSha256Impl(str, keyStr)
 }

src/filters/date.ts

@@ -3,14 +3,11 @@ import { FilterImpl } from '../template'
 import { NormalizedFullOptions } from '../liquid-options'
 
 export function date (this: FilterImpl, v: string | Date, format?: string, timezoneOffset?: number | string) {
-  const size = ((v as string)?.length ?? 0) + ((timezoneOffset as string)?.length ?? 0)
-  this.context.memoryLimit.use(size)
   const date = parseDate(v, this.context.opts, timezoneOffset)
   if (!date) return v
   format = toValue(format)
   format = isNil(format) ? this.context.opts.dateFormat : stringify(format)
-  this.context.memoryLimit.use(format.length)
-  return strftime(date, format, this.context.memoryLimit)
+  return strftime(date, format)
 }
 
 export function date_to_xmlschema (this: FilterImpl, v: string | Date) {
@@ -32,14 +29,13 @@ export function date_to_long_string (this: FilterImpl, v: string | Date, type?:
 function stringify_date (this: FilterImpl, v: string | Date, month_type: string, type?: string, style?: string) {
   const date = parseDate(v, this.context.opts)
   if (!date) return v
-  const ml = this.context.memoryLimit
   if (type === 'ordinal') {
     const d = date.getDate()
     return style === 'US'
-      ? strftime(date, `${month_type} ${d}%q, %Y`, ml)
-      : strftime(date, `${d}%q ${month_type} %Y`, ml)
+      ? strftime(date, `${month_type} ${d}%q, %Y`)
+      : strftime(date, `${d}%q ${month_type} %Y`)
   }
-  return strftime(date, `%d ${month_type} %Y`, ml)
+  return strftime(date, `%d ${month_type} %Y`)
 }
 
 function parseDate (v: string | Date, opts: NormalizedFullOptions, timezoneOffset?: number | string): LiquidDate | undefined {

src/filters/html.ts

@@ -18,7 +18,6 @@ const unescapeMap: Record<string, string> = {
 
 export function escape (this: FilterImpl, str: string) {
   str = stringify(str)
-  this.context.memoryLimit.use(str.length)
   return str.replace(/&|<|>|"|'/g, m => escapeMap[m])
 }
 
@@ -28,7 +27,6 @@ export function xml_escape (this: FilterImpl, str: string) {
 
 function unescape (this: FilterImpl, str: string) {
   str = stringify(str)
-  this.context.memoryLimit.use(str.length)
   return str.replace(/&(amp|lt|gt|#34|#39);/g, m => unescapeMap[m])
 }
 
@@ -38,7 +36,6 @@ export function escape_once (this: FilterImpl, str: string) {
 
 export function newline_to_br (this: FilterImpl, v: string) {
   const str = stringify(v)
-  this.context.memoryLimit.use(str.length)
   return str.replace(/\r?\n/gm, '<br />\n')
 }
 
@@ -46,7 +43,6 @@ export function newline_to_br (this: FilterImpl, v: string) {
 // equivalent is O(n^2) in V8 on unclosed openers.
 export function strip_html (this: FilterImpl, v: string) {
   const str = stringify(v)
-  this.context.memoryLimit.use(str.length)
   const blocks = new Map([['<script', '</script>'], ['<style', '</style>'], ['<!--', '-->'], ['<', '>']])
   let out = ''
   let i = 0
@@ -60,7 +56,7 @@ export function strip_html (this: FilterImpl, v: string) {
       if (e >= 0) { i = e + closer.length; break }
       blocks.delete(opener)
     }
-    if (i === lt) return out + str.slice(lt)
+    if (i <= lt) return out + str.slice(lt)
   }
   return out
 }

src/filters/math.ts

@@ -8,14 +8,13 @@ export const divided_by = argumentsToNumber((dividend: number, divisor: number,
 export const floor = argumentsToNumber(Math.floor)
 export const minus = argumentsToNumber((v: number, arg: number) => v - arg)
 export const plus = argumentsToNumber((lhs: number, rhs: number) => lhs + rhs)
-export const modulo = argumentsToNumber((v: number, arg: number) => v % arg)
+export const modulo = argumentsToNumber((v: number, arg: number) => ((v % arg) + arg) % arg)
 export const times = argumentsToNumber((v: number, arg: number) => v * arg)
 
 export function round (v: number, arg = 0) {
   v = toNumber(v)
   arg = toNumber(arg)
   const amp = Math.pow(10, arg)
-  const scaled = v * amp
-  // Round half away from zero
-  return Math.sign(v) * Math.round(Math.abs(scaled)) / amp
+  const scaled = (v * amp) * (1 + Number.EPSILON)
+  return Math.round(scaled) / amp
 }

src/filters/misc.ts

@@ -9,17 +9,21 @@ function defaultFilter<T1 extends boolean, T2> (this: FilterImpl, value: T1, def
   return isFalsy(value, this.context) ? defaultValue : value
 }
 
-function json (value: any, space = 0) {
-  return JSON.stringify(value, null, space)
+function json (this: FilterImpl, value: any, space = 0) {
+  return JSON.stringify(value, undefined, space)
 }
 
-function inspect (value: any, space = 0) {
+function inspect (this: FilterImpl, value: any, space = 0) {
   const ancestors: object[] = []
   return JSON.stringify(value, function (this: unknown, _key: unknown, value: any) {
-    if (typeof value !== 'object' || value === null) return value
+    if (typeof value !== 'object' || value === null) {
+      return value
+    }
     // `this` is the object that value is contained in, i.e., its direct parent.
     while (ancestors.length > 0 && ancestors[ancestors.length - 1] !== this) ancestors.pop()
-    if (ancestors.includes(value)) return '[Circular]'
+    if (ancestors.includes(value)) {
+      return '[Circular]'
+    }
     ancestors.push(value)
     return value
   }, space)

src/filters/string.ts

@@ -22,7 +22,6 @@ export function append (this: FilterImpl, v: string, arg: string) {
   assert(arguments.length === 2, 'append expect 2 arguments')
   const lhs = stringify(v)
   const rhs = stringify(arg)
-  this.context.memoryLimit.use(lhs.length + rhs.length)
   return lhs + rhs
 }
 
@@ -30,16 +29,13 @@ export function prepend (this: FilterImpl, v: string, arg: string) {
   assert(arguments.length === 2, 'prepend expect 2 arguments')
   const lhs = stringify(v)
   const rhs = stringify(arg)
-  this.context.memoryLimit.use(lhs.length + rhs.length)
   return rhs + lhs
 }
 
 export function lstrip (this: FilterImpl, v: string, chars?: string) {
   const str = stringify(v)
-  this.context.memoryLimit.use(str.length)
   if (chars) {
     chars = stringify(chars)
-    this.context.memoryLimit.use(chars.length)
     for (let i = 0, set = new Set(chars); i < str.length; i++) {
       if (!set.has(str[i])) return str.slice(i)
     }
@@ -50,34 +46,29 @@ export function lstrip (this: FilterImpl, v: string, chars?: string) {
 
 export function downcase (this: FilterImpl, v: string) {
   const str = stringify(v)
-  this.context.memoryLimit.use(str.length)
   return str.toLowerCase()
 }
 
 export function upcase (this: FilterImpl, v: string) {
   const str = stringify(v)
-  this.context.memoryLimit.use(str.length)
   return stringify(str).toUpperCase()
 }
 
 export function remove (this: FilterImpl, v: string, arg: string) {
   const str = stringify(v)
   arg = stringify(arg)
-  this.context.memoryLimit.use(str.length + arg.length)
   return str.split(arg).join('')
 }
 
 export function remove_first (this: FilterImpl, v: string, l: string) {
   const str = stringify(v)
   l = stringify(l)
-  this.context.memoryLimit.use(str.length + l.length)
   return str.replace(l, '')
 }
 
 export function remove_last (this: FilterImpl, v: string, l: string) {
   const str = stringify(v)
   const pattern = stringify(l)
-  this.context.memoryLimit.use(str.length + pattern.length)
   const index = str.lastIndexOf(pattern)
   if (index === -1) return str
   return str.substring(0, index) + str.substring(index + pattern.length)
@@ -85,10 +76,8 @@ export function remove_last (this: FilterImpl, v: string, l: string) {
 
 export function rstrip (this: FilterImpl, str: string, chars?: string) {
   str = stringify(str)
-  this.context.memoryLimit.use(str.length)
   if (chars) {
     chars = stringify(chars)
-    this.context.memoryLimit.use(chars.length)
     for (let i = str.length - 1, set = new Set(chars); i >= 0; i--) {
       if (!set.has(str[i])) return str.slice(0, i + 1)
     }
@@ -99,7 +88,6 @@ export function rstrip (this: FilterImpl, str: string, chars?: string) {
 
 export function split (this: FilterImpl, v: string, arg: string) {
   const str = stringify(v)
-  this.context.memoryLimit.use(str.length)
   const arr = str.split(stringify(arg))
   // align to ruby split, which is the behavior of shopify/liquid
   // see: https://ruby-doc.org/core-2.4.0/String.html#method-i-split
@@ -109,10 +97,8 @@ export function split (this: FilterImpl, v: string, arg: string) {
 
 export function strip (this: FilterImpl, v: string, chars?: string) {
   const str = stringify(v)
-  this.context.memoryLimit.use(str.length)
   if (chars) {
     const set = new Set(stringify(chars))
-    this.context.memoryLimit.use(set.size)
     let i = 0
     let j = str.length - 1
     while (set.has(str[i])) i++
@@ -124,13 +110,11 @@ export function strip (this: FilterImpl, v: string, chars?: string) {
 
 export function strip_newlines (this: FilterImpl, v: string) {
   const str = stringify(v)
-  this.context.memoryLimit.use(str.length)
   return str.replace(/\r?\n/gm, '')
 }
 
 export function capitalize (this: FilterImpl, str: string) {
   str = stringify(str)
-  this.context.memoryLimit.use(str.length)
   return str.charAt(0).toUpperCase() + str.slice(1).toLowerCase()
 }
 
@@ -139,8 +123,6 @@ export function replace (this: FilterImpl, v: string, pattern: string, replaceme
   pattern = stringify(pattern)
   replacement = stringify(replacement)
   const parts = str.split(pattern)
-  const outputSize = str.length + (parts.length - 1) * (replacement.length - pattern.length)
-  this.context.memoryLimit.use(outputSize)
   return parts.join(replacement)
 }
 
@@ -148,7 +130,6 @@ export function replace_first (this: FilterImpl, v: string, arg1: string, arg2:
   const str = stringify(v)
   arg1 = stringify(arg1)
   arg2 = stringify(arg2)
-  this.context.memoryLimit.use(str.length + arg1.length + arg2.length)
   return str.replace(arg1, () => arg2)
 }
 
@@ -156,7 +137,6 @@ export function replace_last (this: FilterImpl, v: string, arg1: string, arg2: s
   const str = stringify(v)
   const pattern = stringify(arg1)
   const replacement = stringify(arg2)
-  this.context.memoryLimit.use(str.length + pattern.length + replacement.length)
   const index = str.lastIndexOf(pattern)
   if (index === -1) return str
   return str.substring(0, index) + replacement + str.substring(index + pattern.length)
@@ -165,7 +145,6 @@ export function replace_last (this: FilterImpl, v: string, arg1: string, arg2: s
 export function truncate (this: FilterImpl, v: string, l = 50, o = '...') {
   const str = stringify(v)
   o = stringify(o)
-  this.context.memoryLimit.use(str.length + o.length)
   if (str.length <= l) return v
   return str.substring(0, l - o.length) + o
 }
@@ -173,7 +152,6 @@ export function truncate (this: FilterImpl, v: string, l = 50, o = '...') {
 export function truncatewords (this: FilterImpl, v: string, words = 15, o = '...') {
   const str = stringify(v)
   o = stringify(o)
-  this.context.memoryLimit.use(str.length + o.length)
   const arr = str.split(/\s+/)
   if (words <= 0) words = 1
   let ret = arr.slice(0, words).join(' ')
@@ -183,13 +161,11 @@ export function truncatewords (this: FilterImpl, v: string, words = 15, o = '...
 
 export function normalize_whitespace (this: FilterImpl, v: string) {
   const str = stringify(v)
-  this.context.memoryLimit.use(str.length)
   return str.replace(/\s+/g, ' ')
 }
 
 export function number_of_words (this: FilterImpl, input: string, mode?: 'cjk' | 'auto') {
   const str = stringify(input)
-  this.context.memoryLimit.use(str.length)
   input = str.trim()
   if (!input) return 0
   switch (mode) {
@@ -209,7 +185,6 @@ export function number_of_words (this: FilterImpl, input: string, mode?: 'cjk' |
 
 export function array_to_sentence_string (this: FilterImpl, array: unknown[], connector = 'and') {
   connector = stringify(connector)
-  this.context.memoryLimit.use(array.length + connector.length)
   switch (array.length) {
     case 0:
       return ''

src/liquid-options.ts

@@ -38,7 +38,7 @@ export interface LiquidOptions {
   strictVariables?: boolean;
   /** Catch all errors instead of exit upon one. Please note that render errors won't be reached when parse fails. */
   catchAllErrors?: boolean;
-  /** Hide scope variables from prototypes, useful when you're passing a not sanitized object into LiquidJS or need to hide prototypes from templates. */
+  /** Limit template property reads on plain scope objects to own properties. Defaults to `true`. See https://liquidjs.com/tutorials/security-model.html */
   ownPropertyOnly?: boolean;
   /** Modifies the behavior of `strictVariables`. If set, a single undefined variable will *not* cause an exception in the context of the `if`/`elsif`/`unless` tag and the `default` filter. Instead, it will evaluate to `false` and `null`, respectively. Irrelevant if `strictVariables` is not set. Defaults to `false`. **/
   lenientIf?: boolean;
@@ -76,8 +76,6 @@ export interface LiquidOptions {
   templates?: {[key: string]: string};
   /** the global scope passed down to all partial and layout templates, i.e. templates included by `include`, `layout` and `render` tags. */
   globals?: object;
-  /** Whether or not to keep value type when writing the Output, not working for streamed rendering. Defaults to `false`. */
-  keepOutputType?: boolean;
   /** Default escape filter applied to output values, when set, you'll have to add `| raw` for values don't need to be escaped. Defaults to `undefined`. */
   outputEscape?: OutputEscapeOption;
   /** An object of operators for conditional statements. Defaults to the regular Liquid operators. */
@@ -86,10 +84,12 @@ export interface LiquidOptions {
   orderedFilterParameters?: boolean;
   /** For DoS handling, limit total length of templates parsed in one `parse()` call. A typical PC can handle 1e8 (100M) characters without issues. */
   parseLimit?: number;
-  /** For DoS handling, limit total time (in ms) for each `render()` call. */
-  renderLimit?: number;
-  /** For DoS handling, limit new objects creation, including array concat/join/strftime, etc. A typical PC can handle 1e9 (1G) memory without issue. */
-  memoryLimit?: number;
+  /** For DoS handling, limit total renders of tag/HTML/output in one `render()` call. */
+  templateLimit?: number;
+  /** For DoS handling, limit total output length in one `render()` call. */
+  outputLengthLimit?: number;
+  /** For DoS handling, limit nesting depth of `{% render %}`, `{% include %}`, and `{% layout %}` tags. Defaults to `128`. */
+  maxDepth?: number;
 }
 
 export interface RenderOptions {
@@ -109,12 +109,10 @@ export interface RenderOptions {
    * Same as `ownPropertyOnly` on LiquidOptions, but only for current render() call
    */
   ownPropertyOnly?: boolean;
-  /** For DoS handling, limit total renders of tag/HTML/output in one `render()` call. A typical PC can handle 1e5 renders of typical templates per second. */
+  /** For DoS handling, limit total renders of tag/HTML/output in one `render()` call. */
   templateLimit?: number;
-  /** For DoS handling, limit total time (in ms) for each `render()` call. */
-  renderLimit?: number;
-  /** For DoS handling, limit new objects creation, including array concat/join/strftime, etc. A typical PC can handle 1e9 (1G) memory without issue.. */
-  memoryLimit?: number;
+  /** For DoS handling, limit total output length in one `render()` call. */
+  outputLengthLimit?: number;
 }
 
 export interface RenderFileOptions extends RenderOptions {
@@ -157,11 +155,11 @@ export interface NormalizedFullOptions extends NormalizedOptions {
   preserveTimezones: boolean;
   greedy: boolean;
   globals: object;
-  keepOutputType: boolean;
   operators: Operators;
   parseLimit: number;
-  renderLimit: number;
-  memoryLimit: number;
+  templateLimit: number;
+  outputLengthLimit: number;
+  maxDepth: number;
 }
 
 export const defaultOptions: NormalizedFullOptions = {
@@ -193,19 +191,19 @@ export const defaultOptions: NormalizedFullOptions = {
   ownPropertyOnly: true,
   lenientIf: false,
   globals: {},
-  keepOutputType: false,
   operators: defaultOperators,
-  memoryLimit: Infinity,
   parseLimit: Infinity,
-  renderLimit: Infinity
+  templateLimit: Infinity,
+  outputLengthLimit: Infinity,
+  maxDepth: 128
 }
 
 export function normalize (options: LiquidOptions): NormalizedFullOptions {
-  if (options.hasOwnProperty('root')) {
-    if (!options.hasOwnProperty('partials')) options.partials = options.root
-    if (!options.hasOwnProperty('layouts')) options.layouts = options.root
+  if ('root' in options) {
+    if (!('partials' in options)) options.partials = options.root
+    if (!('layouts' in options)) options.layouts = options.root
   }
-  if (options.hasOwnProperty('cache')) {
+  if ('cache' in options) {
     let cache: LiquidCache | undefined
     if (typeof options.cache === 'number') cache = options.cache > 0 ? new LRU(options.cache) : undefined
     else if (typeof options.cache === 'object') cache = options.cache

src/liquid.ts

@@ -1,6 +1,6 @@
 import { Context } from './context'
-import { toPromise, toValueSync, isFunction, forOwn, isString, strictUniq } from './util'
-import { TagClass, createTagClass, TagImplOptions, FilterImplOptions, Template, Value, StaticAnalysisOptions, StaticAnalysis, analyze, analyzeSync, SegmentArray } from './template'
+import { toPromise, toValueSync, forOwn, isString, strictUniq } from './util'
+import { TagClass, FilterImplOptions, Template, Value, StaticAnalysisOptions, StaticAnalysis, analyze, analyzeSync, SegmentArray } from './template'
 import { LookupType } from './fs/loader'
 import { Render } from './render'
 import { Parser } from './parser'
@@ -101,8 +101,8 @@ export class Liquid {
   public registerFilter (name: string, filter: FilterImplOptions) {
     this.filters[name] = filter
   }
-  public registerTag (name: string, tag: TagClass | TagImplOptions) {
-    this.tags[name] = isFunction(tag) ? tag : createTagClass(tag)
+  public registerTag (name: string, tag: TagClass) {
+    this.tags[name] = tag
   }
   public plugin (plugin: (this: Liquid, L: typeof Liquid) => void) {
     return plugin.call(this, Liquid)

src/parser/tokenizer.spec.ts

@@ -522,6 +522,14 @@ describe('Tokenizer', function () {
       expect(new Tokenizer('contains b').matchTrie(opTrie)).toBe(8)
     })
   })
+  describe('#createTrie()', function () {
+    it('should return the same trie for the same input', () => {
+      expect(createTrie(defaultOperators)).toBe(createTrie(defaultOperators))
+    })
+    it('should return distinct tries for distinct inputs', () => {
+      expect(createTrie({ foo: 1 })).not.toBe(createTrie({ foo: 1 }))
+    })
+  })
   describe('#readLiquidTagTokens', () => {
     it('should read newline terminated tokens', () => {
       const tokenizer = new Tokenizer('echo \'hello\'')

src/render/expression.ts

@@ -67,7 +67,6 @@ export function evalQuotedToken (token: QuotedToken) {
 function * evalRangeToken (token: RangeToken, ctx: Context) {
   const low: number = yield evalToken(token.lhs, ctx)
   const high: number = yield evalToken(token.rhs, ctx)
-  ctx.memoryLimit.use(high - low + 1)
   return range(+low, +high + 1)
 }
 

src/render/render.ts

@@ -1,28 +1,21 @@
-import { getPerformance } from '../util/performance'
 import { toPromise, RenderError, LiquidErrors, LiquidError } from '../util'
 import { Context } from '../context'
 import { Template } from '../template'
-import { Emitter, KeepingTypeEmitter, StreamedEmitter, SimpleEmitter } from '../emitters'
+import { Emitter, StreamedEmitter, SimpleEmitter } from '../emitters'
 
 export class Render {
   public renderTemplatesToNodeStream (templates: Template[], ctx: Context): NodeJS.ReadableStream {
-    const emitter = new StreamedEmitter()
+    const emitter = new StreamedEmitter(ctx.outputLengthLimit)
     Promise.resolve().then(() => toPromise(this.renderTemplates(templates, ctx, emitter)))
       .then(() => emitter.end(), err => emitter.error(err))
     return emitter.stream
   }
-  public * renderTemplates (templates: Template[], ctx: Context, emitter?: Emitter): IterableIterator<any> {
-    if (!emitter) {
-      emitter = ctx.opts.keepOutputType ? new KeepingTypeEmitter() : new SimpleEmitter()
-    }
-    ctx.renderLimit.check(getPerformance().now())
+  public * renderTemplates (templates: Template[], ctx: Context, emitter: Emitter = new SimpleEmitter(ctx.outputLengthLimit)): IterableIterator<any> {
     const errors = []
     for (const tpl of templates) {
-      ctx.renderLimit.check(getPerformance().now())
+      ctx.templateLimit.use(1)
       try {
-        // if tpl.render supports emitter, it'll return empty `html`
         const html = yield tpl.render(ctx, emitter)
-        // if not, it'll return an `html`, write to the emitter for it
         html && emitter.write(html)
         if (ctx.breakCalled || ctx.continueCalled) break
       } catch (e) {

src/tags/block.ts

@@ -1,4 +1,4 @@
-import { BlockMode, createScope } from '../context'
+import { BlockMode } from '../context'
 import { isTagToken } from '../util'
 import { BlockDrop } from '../drop'
 import { Liquid, TagToken, TopLevelToken, Template, Context, Emitter, Tag } from '..'
@@ -38,7 +38,7 @@ export default class extends Tag {
       if (stack.includes(self)) throw new Error('block tag cannot be nested')
 
       stack.push(self)
-      ctx.push(createScope({ block: superBlock }))
+      ctx.push({ block: superBlock })
       yield liquid.renderer.renderTemplates(templates, ctx, emitter)
       ctx.pop()
       stack.pop()

src/tags/for.ts

@@ -1,6 +1,5 @@
 import { Hash, ValueToken, Liquid, Tag, evalToken, Emitter, TagToken, TopLevelToken, Context, Template, ParseStream } from '..'
 import { assertEmpty, isValueToken, toEnumerable } from '../util'
-import { createScope } from '../context/scope'
 import { ForloopDrop } from '../drop/forloop-drop'
 import { Parser } from '../parser'
 import { Arguments } from '../template'
@@ -43,15 +42,8 @@ export default class extends Tag {
   }
   * render (ctx: Context, emitter: Emitter): Generator<unknown, void | string, Template[]> {
     const r = this.liquid.renderer
-    let collection = toEnumerable(yield evalToken(this.collection, ctx))
-
-    if (!collection.length) {
-      yield r.renderTemplates(this.elseTemplates, ctx, emitter)
-      return
-    }
-
     const continueKey = 'continue-' + this.variable + '-' + this.collection.getText()
-    ctx.push(createScope({ continue: ctx.getRegister(continueKey, {}) }))
+    ctx.push({ continue: ctx.getRegister(continueKey, {}) })
     const hash = (yield this.hash.render(ctx)) as Record<string, any>
     ctx.pop()
 
@@ -59,6 +51,7 @@ export default class extends Tag {
       ? Object.keys(hash).filter(x => MODIFIERS.includes(x))
       : MODIFIERS.filter(x => hash[x] !== undefined)
 
+    let collection = toEnumerable(yield evalToken(this.collection, ctx))
     collection = modifiers.reduce((collection, modifier: valueOf<typeof MODIFIERS>) => {
       if (modifier === 'offset') return offset(collection, hash['offset'])
       if (modifier === 'limit') return limit(collection, hash['limit'])
@@ -66,8 +59,15 @@ export default class extends Tag {
     }, collection)
 
     ctx.setRegister(continueKey, (hash['offset'] || 0) + collection.length)
-    const scope = createScope({ forloop: new ForloopDrop(collection.length, this.collection.getText(), this.variable) })
-    ctx.push(scope)
+
+    if (!collection.length) {
+      yield r.renderTemplates(this.elseTemplates, ctx, emitter)
+      return
+    }
+
+    if (!this.templates.length) return
+
+    const scope = ctx.push({ forloop: new ForloopDrop(collection.length, this.collection.getText(), this.variable) })
     for (const item of collection) {
       scope[this.variable] = item
       ctx.continueCalled = ctx.breakCalled = false

src/tags/include.ts

@@ -1,5 +1,5 @@
 import { Template, ValueToken, TopLevelToken, Liquid, Tag, assert, evalToken, Hash, Emitter, TagToken, Context } from '..'
-import { BlockMode, createScope, Scope } from '../context'
+import { BlockMode, Scope } from '../context'
 import { Parser } from '../parser'
 import { Argument, Arguments, PartialScope } from '../template'
 import { isString, isValueToken } from '../util'
@@ -28,6 +28,7 @@ export default class extends Tag {
     this.hash = new Hash(tokenizer, liquid.options.jekyllInclude || liquid.options.keyValueSeparator)
   }
   * render (ctx: Context, emitter: Emitter): Generator<unknown, void, unknown> {
+    ctx.depthLimit.use(1)
     const { liquid, hash, withVar } = this
     const { renderer } = liquid
     const filepath = (yield renderFilePath(this.file, ctx, liquid)) as string
@@ -36,13 +37,14 @@ export default class extends Tag {
     const saved = ctx.saveRegister('blocks', 'blockMode')
     ctx.setRegister('blocks', {})
     ctx.setRegister('blockMode', BlockMode.OUTPUT)
-    const scope = createScope((yield hash.render(ctx)) as Scope)
+    const scope = (yield hash.render(ctx)) as Scope
     if (withVar) scope[filepath] = yield evalToken(withVar, ctx)
     const templates = (yield liquid._parsePartialFile(filepath, ctx.sync, this.currentFile)) as Template[]
-    ctx.push(ctx.opts.jekyllInclude ? createScope({ include: scope }) : scope)
+    ctx.push(ctx.opts.jekyllInclude ? { include: scope } : scope)
     yield renderer.renderTemplates(templates, ctx, emitter)
     ctx.pop()
     ctx.restoreRegister(saved)
+    ctx.depthLimit.release(1)
   }
 
   public * children (partials: boolean, sync: boolean): Generator<unknown, Template[]> {

src/tags/layout.ts

@@ -1,5 +1,5 @@
 import { Scope, Template, Liquid, Tag, assert, Emitter, Hash, TagToken, TopLevelToken, Context } from '..'
-import { BlockMode, createScope } from '../context'
+import { BlockMode } from '../context'
 import { parseFilePath, renderFilePath, ParsedFileName } from './render'
 import { BlankDrop } from '../drop'
 import { Parser } from '../parser'
@@ -26,6 +26,7 @@ export default class extends Tag {
       yield renderer.renderTemplates(this.templates, ctx, emitter)
       return
     }
+    ctx.depthLimit.use(1)
     const filepath = (yield renderFilePath(this.file, ctx, liquid)) as string
     assert(filepath, () => `illegal file path "${filepath}"`)
     const templates = (yield liquid._parseLayoutFile(filepath, ctx.sync, this.currentFile)) as Template[]
@@ -40,9 +41,10 @@ export default class extends Tag {
     ctx.setRegister('blockMode', BlockMode.OUTPUT)
 
     // render the layout file use stored blocks
-    ctx.push(createScope((yield args.render(ctx)) as Scope))
+    ctx.push((yield args.render(ctx)) as Scope)
     yield renderer.renderTemplates(templates, ctx, emitter)
     ctx.pop()
+    ctx.depthLimit.release(1)
   }
 
   public * children (partials: boolean): Generator<unknown, Template[]> {

src/tags/render.ts

@@ -55,6 +55,7 @@ export default class extends Tag {
     this.hash = new Hash(tokenizer, liquid.options.keyValueSeparator)
   }
   * render (ctx: Context, emitter: Emitter): Generator<unknown, void, unknown> {
+    ctx.depthLimit.use(1)
     const { liquid, hash } = this
     const filepath = (yield renderFilePath(this.file, ctx, liquid)) as string
     assert(filepath, () => `illegal file path "${filepath}"`)
@@ -81,6 +82,7 @@ export default class extends Tag {
       const templates = (yield liquid._parsePartialFile(filepath, childCtx.sync, this.currentFile)) as Template[]
       yield liquid.renderer.renderTemplates(templates, childCtx, emitter)
     }
+    ctx.depthLimit.release(1)
   }
 
   public * children (partials: boolean, sync: boolean): Generator<unknown, Template[]> {

src/tags/tablerow.ts

@@ -1,5 +1,4 @@
 import { isValueToken, toEnumerable } from '../util'
-import { createScope } from '../context/scope'
 import { ValueToken, Liquid, Tag, evalToken, Emitter, Hash, TagToken, TopLevelToken, Context, Template, ParseStream } from '..'
 import { TablerowloopDrop } from '../drop/tablerowloop-drop'
 import { Parser } from '../parser'
@@ -45,12 +44,15 @@ export default class extends Tag {
     const limit = (args.limit === undefined) ? collection.length : args.limit
 
     collection = collection.slice(offset, offset + limit)
+    if (!collection.length) return
+
+    if (!this.templates.length) return
+
     const cols = args.cols || collection.length
 
     const r = this.liquid.renderer
     const tablerowloop = new TablerowloopDrop(collection.length, cols, this.collection.getText(), this.variable)
-    const scope = createScope({ tablerowloop })
-    ctx.push(scope)
+    const scope = ctx.push({ tablerowloop })
 
     for (let idx = 0; idx < collection.length; idx++, tablerowloop.next()) {
       scope[this.variable] = collection[idx]

src/template/index.ts

@@ -1,7 +1,6 @@
 export * from './template'
 export * from './template-impl'
 export * from './tag'
-export * from './tag-options-adapter'
 export * from './filter'
 export * from './filter-impl-options'
 export * from './hash'

src/template/output.spec.ts

@@ -2,7 +2,6 @@ import { toPromise } from '../util'
 import { Context } from '../context'
 import { Output } from '../template'
 import { OutputToken } from '../tokens'
-import { defaultOptions } from '../liquid-options'
 
 describe('Output', function () {
   const emitter: any = { write: (html: string) => (emitter.html += html), html: '' }
@@ -30,59 +29,4 @@ describe('Output', function () {
     await toPromise(output.render(scope, emitter))
     return expect(emitter.html).toBe('FOO')
   })
-  it('should respect to .toString()', async () => {
-    const scope = new Context({ obj: { toString: () => 'FOO' } })
-    const output = new Output(token, liquid)
-    await toPromise(output.render(scope, emitter))
-    return expect(emitter.html).toBe('FOO')
-  })
-  describe('when keepOutputType is enabled', () => {
-    const emitter: any = {
-      write: (html: any) => {
-        if (emitter.keepOutputType && typeof html !== 'string') {
-          emitter.html = html
-        } else {
-          emitter.html += html as string
-        }
-      },
-      html: '',
-      keepOutputType: true
-    }
-    const token = { content: 'foo', input: 'foo' } as OutputToken
-
-    beforeEach(() => { emitter.html = '' })
-
-    it('should respect output variable number type', async () => {
-      const scope = new Context({
-        foo: 42
-      }, { ...defaultOptions, keepOutputType: true })
-      const output = new Output(token, liquid)
-      await toPromise(output.render(scope, emitter))
-      return expect(emitter.html).toBe(42)
-    })
-    it('should respect output variable boolean type', async () => {
-      const scope = new Context({
-        foo: true
-      }, { ...defaultOptions, keepOutputType: true })
-      const output = new Output(token, liquid)
-      await toPromise(output.render(scope, emitter))
-      return expect(emitter.html).toBe(true)
-    })
-    it('should respect output variable object type', async () => {
-      const scope = new Context({
-        foo: 'test'
-      }, { ...defaultOptions, keepOutputType: true })
-      const output = new Output(token, liquid)
-      await toPromise(output.render(scope, emitter))
-      return expect(emitter.html).toBe('test')
-    })
-    it('should respect output variable string type', async () => {
-      const scope = new Context({
-        foo: { a: { b: 42 } }
-      }, { ...defaultOptions, keepOutputType: true })
-      const output = new Output(token, liquid)
-      await toPromise(output.render(scope, emitter))
-      return expect(emitter.html).toEqual({ a: { b: 42 } })
-    })
-  })
 })

src/template/tag-options-adapter.ts

@@ -1,28 +0,0 @@
-import { isFunction } from '../util'
-import { Hash } from './hash'
-import { Tag, TagClass, TagRenderReturn } from './tag'
-import { TagToken, TopLevelToken } from '../tokens'
-import { Emitter } from '../emitters'
-import { Context } from '../context'
-import type { Liquid } from '../liquid'
-
-export interface TagImplOptions {
-  [key: string]: any
-  parse?: (this: Tag & TagImplOptions, token: TagToken, remainingTokens: TopLevelToken[]) => void;
-  render: (this: Tag & TagImplOptions, ctx: Context, emitter: Emitter, hash: Record<string, any>) => TagRenderReturn;
-}
-
-export function createTagClass (options: TagImplOptions): TagClass {
-  return class extends Tag {
-    constructor (token: TagToken, tokens: TopLevelToken[], liquid: Liquid) {
-      super(token, tokens, liquid)
-      if (isFunction(options.parse)) {
-        options.parse.call(this, token, tokens)
-      }
-    }
-    * render (ctx: Context, emitter: Emitter): TagRenderReturn {
-      const hash = (yield new Hash(this.token.args, ctx.opts.keyValueSeparator).render(ctx)) as Record<string, any>
-      return yield options.render.call(this, ctx, emitter, hash)
-    }
-  }
-}

src/util/limiter.ts

@@ -14,6 +14,11 @@ export class Limiter {
       this.base += +count
     }
   }
+  release (count: number) {
+    if (+count > 0) {
+      this.base -= +count
+    }
+  }
   check (count: number) {
     if (+count > 0) {
       assert(+count <= this.limit, this.message)

src/util/operator-trie.ts

@@ -10,7 +10,16 @@ export type Trie<T> = {
   needBoundary?: true
 } & Record<string, any>
 
+// Tries are built once per input object and reused: the Tokenizer rebuilds them
+// on every instantiation, but `input` (operators/literalValues) is a stable
+// reference. WeakMap-keying by `input` lets short-lived operator objects (and
+// their tries) be garbage collected. The returned trie is treated as read-only
+// by callers (matchTrie only reads it); do not mutate it.
+const trieCache = new WeakMap<TrieInput<any>, Trie<any>>()
+
 export function createTrie<T = any> (input: TrieInput<T>): Trie<T> {
+  const cached = trieCache.get(input)
+  if (cached) return cached
   const trie: Trie<T> = {}
   for (const [name, data] of Object.entries(input)) {
     let node = trie
@@ -29,5 +38,6 @@ export function createTrie<T = any> (input: TrieInput<T>): Trie<T> {
     node.data = data
     node.end = true
   }
+  trieCache.set(input, trie)
   return trie
 }

src/util/strftime.spec.ts

@@ -188,6 +188,14 @@ describe('util/strftime', function () {
     it('should have higher priority than H', () => {
       expect(t(then, '%0H')).toBe('03')
     })
+    it('should allow pad width up to MAX_STRFTIME_PAD', () => {
+      expect(t(now, '%100000d').length).toBe(100000)
+      expect(t(now, `%${1_000_000}d`).length).toBe(1_000_000)
+    })
+    it('should throw when pad width exceeds MAX_STRFTIME_PAD', () => {
+      expect(() => t(now, `%${1024 * 1024 + 1}d`)).toThrow('strftime pad width limit exceeded')
+      expect(() => t(now, '%5000000d')).toThrow('strftime pad width limit exceeded')
+    })
   })
   describe('modifier field', () => {
     it('should ignore E modifier', () => {

src/util/strftime.ts

@@ -1,13 +1,15 @@
 import { changeCase, padStart, padEnd } from './underscore'
 import { LiquidDate } from './liquid-date'
-import type { Limiter } from './limiter'
+import { assert } from './assert'
+
+/** Per-conversion numeric width cap for strftime (%N, %15d, …). */
+export const MAX_STRFTIME_PAD = 1024 * 1024
 
 const rFormat = /%([-_0^#:]+)?(\d+)?([EO])?(.)/
 interface FormatOptions {
   flags: Record<string, boolean>;
   width?: string;
   modifier?: string;
-  memoryLimit?: Pick<Limiter, 'use'>;
 }
 
 // prototype extensions
@@ -98,8 +100,8 @@ const formatCodes: Record<string, FormatCodeHandler> = {
   M: (d: LiquidDate) => d.getMinutes(),
   N: (d: LiquidDate, opts: FormatOptions) => {
     const width = Number(opts.width) || 9
+    assertPadWidth(width)
     const str = String(d.getMilliseconds()).slice(0, width)
-    opts.memoryLimit?.use(width - str.length)
     return padEnd(str, width, '0')
   },
   p: (d: LiquidDate) => (d.getHours() < 12 ? 'AM' : 'PM'),
@@ -123,25 +125,29 @@ const formatCodes: Record<string, FormatCodeHandler> = {
 }
 formatCodes.h = formatCodes.b
 
-export function strftime (d: LiquidDate, formatStr: string, memoryLimit?: Pick<Limiter, 'use'>) {
+export function strftime (d: LiquidDate, formatStr: string) {
   let output = ''
   let remaining = formatStr
   let match
   while ((match = rFormat.exec(remaining))) {
     output += remaining.slice(0, match.index)
     remaining = remaining.slice(match.index + match[0].length)
-    output += format(d, match, memoryLimit)
+    output += format(d, match)
   }
   return output + remaining
 }
 
-function format (d: LiquidDate, match: RegExpExecArray, memoryLimit?: Pick<Limiter, 'use'>) {
+function assertPadWidth (width: number) {
+  assert(width <= MAX_STRFTIME_PAD, 'strftime pad width limit exceeded')
+}
+
+function format (d: LiquidDate, match: RegExpExecArray) {
   const [input, flagStr = '', width, modifier, conversion] = match
   const convert = formatCodes[conversion]
   if (!convert) return input
   const flags: Record<string, boolean> = {}
   for (const flag of flagStr) flags[flag] = true
-  let ret = String(convert(d, { flags, width, modifier, memoryLimit }))
+  let ret = String(convert(d, { flags, width, modifier }))
   let padChar = padSpaceChars.has(conversion) ? ' ' : '0'
   let padWidth = Number(width) || padWidths[conversion] || 0
   if (flags['^']) ret = ret.toUpperCase()
@@ -149,6 +155,6 @@ function format (d: LiquidDate, match: RegExpExecArray, memoryLimit?: Pick<Limit
   if (flags['_']) padChar = ' '
   else if (flags['0']) padChar = '0'
   if (flags['-']) padWidth = 0
-  memoryLimit?.use(Number(padWidth) - ret.length)
+  else assertPadWidth(padWidth)
   return padStart(ret, padWidth, padChar)
 }

src/util/underscore.ts

@@ -1,10 +1,9 @@
 import { Drop } from '../drop/drop'
 
 export const toString = Object.prototype.toString
+export const hasOwnProperty = Object.prototype.hasOwnProperty
 const toLowerCase = String.prototype.toLowerCase
 
-export const hasOwnProperty = Object.hasOwnProperty
-
 export function isString (value: any): value is string {
   return typeof value === 'string'
 }
@@ -42,6 +41,12 @@ export function stringify (value: any): string {
   return String(value)
 }
 
+export function readArrayElement (arr: any[], index: number, ownPropertyOnly: boolean) {
+  if (index < 0) index = arr.length + index
+  if (ownPropertyOnly && !hasOwnProperty.call(arr, index)) return undefined
+  return arr[index]
+}
+
 export function toEnumerable<T = unknown> (val: any): T[] {
   val = toValue(val)
   if (isArray(val)) return val
@@ -84,8 +89,7 @@ export function isUndefined (value: any): boolean {
 }
 
 export function isArray (value: any): value is any[] {
-  // be compatible with IE 8
-  return toString.call(value) === '[object Array]'
+  return Array.isArray(value)
 }
 
 export function isArrayLike (value: any): value is any[] {

test/demo/test.sh

@@ -14,9 +14,9 @@ for demo in $(ls demo); do
   npm link liquidjs
 
   if npm test; then
-    echo [success] demo/webpack
+    echo "[success] demo/$demo"
   else
-    echo [fail] demo/webpack
+    echo "[fail] demo/$demo"
     exit 1
   fi
   cd -

test/e2e/issues.spec.ts

@@ -1,4 +1,4 @@
-import { TopLevelToken, TagToken, Tokenizer, Context, Liquid, Drop, toValueSync, LiquidError, IfTag } from '../..'
+import { Tokenizer, Context, Liquid, Drop, toValueSync, LiquidError, IfTag } from '../..'
 import { spawnSync } from 'child_process'
 import { resolve as resolvePath } from 'path'
 const LiquidUMD = require('../../dist/liquid.browser.umd.js').Liquid
@@ -362,33 +362,8 @@ describe('Issues', function () {
     const html = await liquid.parseAndRender(tpl)
     expect(html).toMatch(/^\s*This is a love or luck potion.\s+This is a strength or health or love potion.\s*$/)
   })
-  it('tag registration compatible to v9 #570', async () => {
-    const liquid = new Liquid()
-    liquid.registerTag('metadata_file', {
-      parse (tagToken: TagToken, remainTokens: TopLevelToken[]) {
-        this.str = tagToken.args
-      },
-      async render (ctx: Context) {
-        const content = await Promise.resolve(`{{${this.str}}}`)
-        return this.liquid.parseAndRender(content.toString(), ctx)
-      }
-    })
-    const tpl = '{% metadata_file foo %}'
-    const ctx = { foo: 'FOO' }
-    const html = await liquid.parseAndRender(tpl, ctx)
-    expect(html).toBe('FOO')
-  })
   it('date filter should return parsed input when no format is provided #573', async () => {
     const liquid = new Liquid()
-    liquid.registerTag('metadata_file', {
-      parse (tagToken: TagToken, remainTokens: TopLevelToken[]) {
-        this.str = tagToken.args
-      },
-      async render (ctx: Context) {
-        const content = await Promise.resolve(`{{${this.str}}}`)
-        return this.liquid.parseAndRender(content.toString(), ctx)
-      }
-    })
     const tpl = `{{ 'now' | date }}`
     const html = await liquid.parseAndRender(tpl)
     // sample: Thursday, February 2, 2023 at 6:25 pm +0000
@@ -544,13 +519,6 @@ describe('Issues', function () {
     const result = engine.parseAndRenderSync(`\n{{ "foo" | pos }}`)
     expect(result).toEqual('\n[2,12] foo')
   })
-  it("memoryLimit doesn't work in for tag #776", () => {
-    const engine = new Liquid({
-      memoryLimit: 1e5
-    })
-    const tpl = `{% for i in (1..1000000000) %} {{'a'}} {% endfor %}`
-    expect(() => engine.parseAndRenderSync(tpl)).toThrow('memory alloc limit exceeded, line:1, col:1')
-  })
   it('group_by_exp fails with object as input #785', () => {
     const site = {
       tags: {

test/integration/context/own-property-only.spec.ts

@@ -0,0 +1,54 @@
+import { Liquid } from '../../../src/liquid'
+
+describe('ownPropertyOnly / inherited array indices', function () {
+  const engine = new Liquid({ ownPropertyOnly: true })
+
+  function pollutedArrays () {
+    // eslint-disable-next-line no-extend-native
+    Array.prototype[0] = 'ARRAY_PROTO_POLLUTED'
+    ;(Object.prototype as any).secret = 'OBJECT_PROTO_POLLUTED'
+    const a: any[] = []
+    a.length = 1
+    const o = {}
+    return {
+      a,
+      o,
+      cleanup () {
+        delete (Array.prototype as any)[0]
+        delete (Object.prototype as any).secret
+      }
+    }
+  }
+
+  const cases: [string, (ctx: ReturnType<typeof pollutedArrays>) => object, string][] = [
+    ['{{ a[0] }}', ({ a }) => ({ a }), ''],
+    ['{{ a[-1] }}', ({ a }) => ({ a }), ''],
+    ['{{ o.secret }}', ({ o }) => ({ o }), ''],
+    ['{{ a.first }}', ({ a }) => ({ a }), ''],
+    ['{{ a.last }}', ({ a }) => ({ a }), ''],
+    ['{{ a | first }}', ({ a }) => ({ a }), ''],
+    ['{{ a | last }}', ({ a }) => ({ a }), ''],
+    ['{% assign x = a | first %}{{ x }}', ({ a }) => ({ a }), '']
+  ]
+
+  it.each(cases)('%s', function (src, scopeFn, expected) {
+    const ctx = pollutedArrays()
+    try {
+      expect(engine.parseAndRenderSync(src, scopeFn(ctx))).toBe(expected)
+    } finally {
+      ctx.cleanup()
+    }
+  })
+
+  it('still allows array length and size', function () {
+    const { a, cleanup } = pollutedArrays()
+    try {
+      expect(engine.parseAndRenderSync('{{ a.size }}', { a })).toBe('1')
+      const arr = [1, 2]
+      expect(engine.parseAndRenderSync('{{ arr | first }}', { arr })).toBe('1')
+      expect(engine.parseAndRenderSync('{{ arr[-1] }}', { arr })).toBe('2')
+    } finally {
+      cleanup()
+    }
+  })
+})

test/integration/filters/date.spec.ts

@@ -204,31 +204,21 @@ describe('filters/date', function () {
       return test('{{ "1990-12-31T23:00:00Z" | date: "%Y-%m-%dT%H:%M:%S" }}', '1991-01-01T04:30:00', undefined, optsWithDateFormat)
     })
   })
-  describe('strftime width / memoryLimit', () => {
-    it('should charge memoryLimit for huge numeric strftime widths', () => {
-      const liquid = new Liquid({ memoryLimit: 500 })
-      expect(() => liquid.parseAndRenderSync('{{ d | date: f }}', { d: 'now', f: '%5000000d' }))
-        .toThrow('memory alloc limit exceeded')
-    })
-    it('should charge memoryLimit for array format PoC', () => {
-      const liquid = new Liquid({ memoryLimit: 50, renderLimit: 1e9 })
-      expect(() => liquid.parseAndRenderSync('{{ d | date: f }}', { d: 'now', f: ['a'.repeat(2000000)] }))
-        .toThrow('memory alloc limit exceeded')
-    })
-    it('should charge memoryLimit for object toString format PoC', () => {
-      const liquid = new Liquid({ memoryLimit: 50, renderLimit: 1e9 })
-      const huge = 'a'.repeat(2000000)
-      const f = { toString: () => huge }
-      expect(() => liquid.parseAndRenderSync('{{ d | date: f }}', { d: 'now', f }))
-        .toThrow('memory alloc limit exceeded')
-    })
-    it('should honor numeric strftime pad width when memoryLimit allows', () => {
-      const liquid = new Liquid({ memoryLimit: 1e7 })
+  describe('strftime width', () => {
+    it('should honor numeric strftime pad width', () => {
+      const liquid = new Liquid()
       const out = liquid.parseAndRenderSync('{{ d | date: f }}', { d: 'now', f: '%5000d' })
       expect(out.length).toBe(5000)
-      const tight = new Liquid({ memoryLimit: 100 })
-      expect(() => tight.parseAndRenderSync('{{ d | date: f }}', { d: 'now', f: '%5000d' }))
-        .toThrow('memory alloc limit exceeded')
+    })
+    it('should honor large numeric strftime pad width up to the cap', () => {
+      const liquid = new Liquid()
+      const out = liquid.parseAndRenderSync('{{ d | date: f }}', { d: 'now', f: '%100000d' })
+      expect(out.length).toBe(100000)
+    })
+    it('should throw when numeric strftime pad width is too large', () => {
+      const liquid = new Liquid()
+      expect(() => liquid.parseAndRenderSync('{{ d | date: f }}', { d: 'now', f: '%5000000d' }))
+        .toThrow('strftime pad width limit exceeded')
     })
   })
 })

test/integration/filters/html.spec.ts

@@ -85,5 +85,9 @@ describe('filters/html', function () {
       expect(liquid.parseAndRenderSync('{{"<img\rsrc=x\ronerror=alert(1)>" | strip_html}}')).toBe('')
       expect(liquid.parseAndRenderSync('{{"<svg\nonload=alert(1)>" | strip_html}}')).toBe('')
     })
+    it('should not loop on unclosed openers (GHSA-m7fp-h3p4-hr49)', function () {
+      expect(liquid.parseAndRenderSync('{{ "a<" | strip_html }}')).toBe('a<')
+      expect(liquid.parseAndRenderSync('{{ "hello<world<again" | strip_html }}')).toBe('hello<world<again')
+    })
   })
 })

test/integration/filters/math.spec.ts

@@ -50,6 +50,9 @@ describe('filters/math', function () {
       expect(Number(html)).toBeCloseTo(3.357, 3)
     })
     it('should convert string', () => test('{{ "24" | modulo: "7" }}', '3'))
+    it('should follow divisor sign for negative dividend', () => test('{{ -7 | modulo: 3 }}', '2'))
+    it('should follow divisor sign for negative divisor', () => test('{{ 7 | modulo: -3 }}', '-2'))
+    it('should follow divisor sign for negative float', () => test('{{ -4.5 | modulo: 3 }}', '1.5'))
   })
   describe('plus', function () {
     it('should return "6" for 4,2', () => test('{{ 4 | plus: 2 }}', '6'))
@@ -70,6 +73,10 @@ describe('filters/math', function () {
     it('should return "183.36" for 183.357,2',
       () => test('{{183.357|round: 2}}', '183.36'))
     it('should convert string to number', () => test('{{"2.7"|round}}', '3'))
+    it('odd number 1.005 should round correctly', () => test('{{1.005|round:2}}', '1.01'))
+    it('odd number -1.005 should round correctly', () => test('{{num|round:2}}', { num: -1.005 }, '-1.01'))
+    it('odd number 9.075 should round correctly', () => test('{{9.075|round:2}}', '9.08'))
+    it('odd number -9.075 should round correctly', () => test('{{num|round:2}}', { num: -9.075 }, '-9.08'))
   })
   describe('times', function () {
     it('should return "6" for 3,2', () => test('{{ 3 | times: 2 }}', '6'))

test/integration/liquid/dos.spec.ts

@@ -4,15 +4,18 @@ import { mock, restore } from '../../stub/mockfs'
 describe('DoS related', function () {
   describe('#parseLimit', function () {
     afterEach(restore)
+
     it('should throw when parse limit exceeded', async () => {
       const noLimit = new Liquid()
       const limit10 = new Liquid({ parseLimit: 10 })
       const limit90 = new Liquid({ parseLimit: 90 })
       const template = '{% capture bar %}{{ foo | bar: 3, a[3] }}{% endcapture %}'
+
       await expect(noLimit.parseAndRender(template)).resolves.toBe('')
       await expect(limit10.parseAndRender(template)).rejects.toThrow('parse length limit exceeded')
       await expect(limit90.parseAndRender(template)).resolves.toBe('')
     })
+
     it('should take included template into account', async () => {
       mock({
         '/small': 'Lorem ipsum',
@@ -23,78 +26,151 @@ describe('DoS related', function () {
       await expect(liquid.parseAndRender('{% include "large" %}')).rejects.toThrow('parse length limit exceeded')
     })
   })
-  describe('#renderLimit', () => {
+
+  describe('#templateLimit', () => {
     it('should throw when rendering too many templates', async () => {
       const src = '{% for i in (1..1000) %}{{i}},{% endfor %}'
       const noLimit = new Liquid()
-      const limitSmall = new Liquid({ renderLimit: 0.01 })
-      const limitLarge = new Liquid({ renderLimit: 2e4 })
+      const limitSmall = new Liquid({ templateLimit: 100 })
+      const limitLarge = new Liquid({ templateLimit: 2001 })
       await expect(noLimit.parseAndRender(src)).resolves.toMatch(/^1,2,3,4,5,.*,999,1000,$/)
-      await expect(limitSmall.parseAndRender(src)).rejects.toThrow('template render limit exceeded')
+      await expect(limitSmall.parseAndRender(src)).rejects.toThrow('template limit exceeded')
       await expect(limitLarge.parseAndRender(src)).resolves.toMatch(/^1,2,3,4,5,.*,999,1000,$/)
     })
+
     it('should support reset when calling render', async () => {
       const src = '{% for i in (1..1000) %}{{i}},{% endfor %}'
-      const liquid = new Liquid({ renderLimit: 0.01 })
-      await expect(liquid.parseAndRender(src)).rejects.toThrow('template render limit exceeded')
-      await expect(liquid.parseAndRender(src, {}, { renderLimit: 1e6 })).resolves.toMatch(/^1,2,3,4,5,.*,999,1000,$/)
+      const liquid = new Liquid({ templateLimit: 100 })
+      await expect(liquid.parseAndRender(src)).rejects.toThrow('template limit exceeded')
+      await expect(liquid.parseAndRender(src, {}, { templateLimit: 2001 })).resolves.toMatch(/^1,2,3,4,5,.*,999,1000,$/)
     })
+
     it('should take partials into account', async () => {
       mock({
         '/small': '{% for i in (1..5) %}{{i}}{% endfor %}',
         '/large': '{% for i in (1..50000000) %}{{i}}{% endfor %}'
       })
-      const liquid = new Liquid({ root: '/', renderLimit: 1000 })
-      await expect(liquid.parseAndRender('{% render "large" %}')).rejects.toThrow('template render limit exceeded')
+      const liquid = new Liquid({ root: '/', templateLimit: 1000 })
+      await expect(liquid.parseAndRender('{% render "large" %}')).rejects.toThrow('template limit exceeded')
       await expect(liquid.parseAndRender('{% render "small" %}')).resolves.toBe('12345')
     })
-    it('should enforce renderLimit when for body has no template nodes', () => {
-      const liquid = new Liquid({ memoryLimit: 1e9, renderLimit: 1 })
-      expect(() => liquid.parseAndRenderSync('{%- for i in (1..5000000) -%}{%- endfor -%}', {}))
-        .toThrow('template render limit exceeded')
-    })
-    it('should enforce renderLimit when tablerow body has no template nodes', () => {
-      const liquid = new Liquid({ memoryLimit: 1e9, renderLimit: 1 })
-      expect(() => liquid.parseAndRenderSync('{%- tablerow i in (1..1000000) cols:1 -%}{%- endtablerow -%}', {}))
-        .toThrow('template render limit exceeded')
-    })
   })
-  describe('#memoryLimit', () => {
-    it('should throw for too many array creation in filters', async () => {
-      const array = Array(1e3).fill(0)
-      const liquid = new Liquid({ memoryLimit: 100 })
-      await expect(liquid.parseAndRender('{{ array | slice: 0, 3 | join }}', { array })).resolves.toBe('0 0 0')
-      await expect(liquid.parseAndRender('{{ array | slice: 0, 300 | join }}', { array })).rejects.toThrow('memory alloc limit exceeded, line:1, col:1')
+
+  describe('#outputLengthLimit', () => {
+    it('should throw when output length exceeded', async () => {
+      const src = '{% for i in (1..1000) %}{{i}},{% endfor %}'
+      const noLimit = new Liquid()
+      const limitSmall = new Liquid({ outputLengthLimit: 10 })
+      const limitLarge = new Liquid({ outputLengthLimit: 5000 })
+      await expect(noLimit.parseAndRender(src)).resolves.toMatch(/^1,2,3,4,5,.*,999,1000,$/)
+      await expect(limitSmall.parseAndRender(src)).rejects.toThrow('output length limit exceeded')
+      await expect(limitLarge.parseAndRender(src)).resolves.toMatch(/^1,2,3,4,5,.*,999,1000,$/)
     })
+
     it('should support reset when calling render', async () => {
-      const array = Array(1e3).fill(0)
-      const liquid = new Liquid({ memoryLimit: 100 })
-      await expect(liquid.parseAndRender('{{ array | slice: 0, 300 | join }}', { array })).rejects.toThrow('memory alloc limit exceeded, line:1, col:1')
-      await expect(liquid.parseAndRender('{{ array | slice: 0, 300 | join }}', { array }, { memoryLimit: 1e3 })).resolves.toBe(Array(300).fill(0).join(' '))
+      const src = '{% for i in (1..1000) %}{{i}},{% endfor %}'
+      const liquid = new Liquid({ outputLengthLimit: 10 })
+      await expect(liquid.parseAndRender(src)).rejects.toThrow('output length limit exceeded')
+      await expect(liquid.parseAndRender(src, {}, { outputLengthLimit: 5000 })).resolves.toMatch(/^1,2,3,4,5,.*,999,1000,$/)
     })
-    it('should throw for too many array iteration in tags', async () => {
-      const array = ['a']
-      const liquid = new Liquid({ memoryLimit: 100 })
-      const src = '{% for i in (1..count) %}{% assign array = array | concat: array %}{% endfor %}{{ array | join }}'
-      await expect(liquid.parseAndRender(src, { array, count: 3 })).resolves.toBe('a a a a a a a a')
-      await expect(liquid.parseAndRender(src, { array, count: 100 })).rejects.toThrow('memory alloc limit exceeded, line:1, col:26')
+
+    it('should take partials into account', async () => {
+      mock({
+        '/small': 'abc',
+        '/large': '{% for i in (1..1000) %}{{i}}{% endfor %}'
+      })
+      const liquid = new Liquid({ root: '/', outputLengthLimit: 10 })
+      await expect(liquid.parseAndRender('{% render "small" %}')).resolves.toBe('abc')
+      await expect(liquid.parseAndRender('{% render "large" %}')).rejects.toThrow('output length limit exceeded')
     })
-    it('should charge pop allocation to memoryLimit', async () => {
-      const array = Array(1e3).fill(0)
-      const liquid = new Liquid({ memoryLimit: 100 })
-      await expect(liquid.parseAndRender('{{ array | pop | size }}', { array })).rejects.toThrow('memory alloc limit exceeded')
+
+    it('should enforce outputLengthLimit in sync render', () => {
+      const liquid = new Liquid({ outputLengthLimit: 5 })
+      expect(() => liquid.parseAndRenderSync('{% for i in (1..100) %}{{i}}{% endfor %}'))
+        .toThrow('output length limit exceeded')
     })
-    it('should charge sample allocation to memoryLimit', async () => {
-      const array = Array(1e3).fill(0)
-      const liquid = new Liquid({ memoryLimit: 100 })
-      await expect(liquid.parseAndRender('{{ array | sample: 1 | size }}', { array })).rejects.toThrow('memory alloc limit exceeded')
-    })
-    it('should charge strip_html input length to memoryLimit', () => {
-      const liquid = new Liquid({ memoryLimit: 100 })
-      expect(() => liquid.parseAndRenderSync('{{ s | strip_html }}', { s: 'a'.repeat(200) }))
-        .toThrow('memory alloc limit exceeded')
+
+    it('should enforce outputLengthLimit in stream render', async () => {
+      const liquid = new Liquid({ outputLengthLimit: 5 })
+      const tpl = liquid.parse('{% for i in (1..100) %}{{i}}{% endfor %}')
+      const stream = liquid.renderToNodeStream(tpl)
+      await expect(new Promise((resolve, reject) => {
+        stream.on('error', reject)
+        stream.on('end', resolve)
+      })).rejects.toThrow('output length limit exceeded')
     })
   })
+
+  describe('#maxDepth', () => {
+    function chain (depth: number, tag: string) {
+      const templates: Record<string, string> = {}
+      for (let i = 0; i < depth; i++) {
+        templates[`t${i}`] = i === depth - 1 ? 'done' : `{% ${tag} "t${i + 1}" %}`
+      }
+      return templates
+    }
+
+    it('should throw when include depth exceeded', async () => {
+      const liquid = new Liquid({ templates: chain(3, 'include'), maxDepth: 2 })
+      await expect(liquid.parseAndRender('{% include "t0" %}')).rejects.toThrow('template depth limit exceeded')
+    })
+
+    it('should allow include within maxDepth', async () => {
+      const liquid = new Liquid({ templates: chain(2, 'include'), maxDepth: 2 })
+      await expect(liquid.parseAndRender('{% include "t0" %}')).resolves.toBe('done')
+    })
+
+    it('should throw when render depth exceeded', async () => {
+      const liquid = new Liquid({ templates: chain(3, 'render'), maxDepth: 2 })
+      await expect(liquid.parseAndRender('{% render "t0" %}')).rejects.toThrow('template depth limit exceeded')
+    })
+
+    it('should allow render within maxDepth', async () => {
+      const liquid = new Liquid({ templates: chain(2, 'render'), maxDepth: 2 })
+      await expect(liquid.parseAndRender('{% render "t0" %}')).resolves.toBe('done')
+    })
+
+    it('should throw when layout depth exceeded', async () => {
+      const liquid = new Liquid({
+        templates: {
+          a: '{% layout "b" %}body-a',
+          b: '{% layout "c" %}body-b',
+          c: 'body-c'
+        },
+        maxDepth: 2
+      })
+      await expect(liquid.parseAndRender('{% layout "a" %}root')).rejects.toThrow('template depth limit exceeded')
+    })
+
+    it('should allow layout within maxDepth', async () => {
+      const liquid = new Liquid({
+        templates: {
+          a: '{% layout "b" %}body-a',
+          b: 'body-b'
+        },
+        maxDepth: 2
+      })
+      await expect(liquid.parseAndRender('{% layout "a" %}root')).resolves.toBe('body-b')
+    })
+
+    it('should not count layout none toward depth', async () => {
+      const liquid = new Liquid({ maxDepth: 0 })
+      await expect(liquid.parseAndRender('{% layout none %}ok')).resolves.toBe('ok')
+    })
+
+    it('should default maxDepth to 128', async () => {
+      const liquid = new Liquid({ templates: chain(128, 'include') })
+      await expect(liquid.parseAndRender('{% include "t0" %}')).resolves.toBe('done')
+      const overflow = new Liquid({ templates: chain(129, 'include') })
+      await expect(overflow.parseAndRender('{% include "t0" %}')).rejects.toThrow('template depth limit exceeded')
+    })
+
+    it('should enforce maxDepth in sync render', () => {
+      const liquid = new Liquid({ templates: chain(3, 'include'), maxDepth: 2 })
+      expect(() => liquid.parseAndRenderSync('{% include "t0" %}')).toThrow('template depth limit exceeded')
+    })
+  })
+
   describe('strip_html ReDoS', () => {
     // Regression for O(n^2) backtracking on unclosed `<script` / `<style` openers.
     // The previous regex stalled the event loop for ~10s on 350KB of `'<script'.repeat`.
@@ -104,11 +180,13 @@ describe('DoS related', function () {
       const payload = '<script'.repeat(50000)
       expect(liquid.parseAndRenderSync('{{ x | strip_html }}', { x: payload })).toBe(payload)
     }, 1000)
+
     it('should handle many unclosed <style openers in linear time', () => {
       const liquid = new Liquid()
       const payload = '<style'.repeat(50000)
       expect(liquid.parseAndRenderSync('{{ x | strip_html }}', { x: payload })).toBe(payload)
     }, 1000)
+
     it('should handle <script openers that have > but no </script> in linear time', () => {
       const liquid = new Liquid()
       const payload = '<script>foo'.repeat(50000)

test/integration/liquid/keepoutput-opt.spec.ts

@@ -1,39 +0,0 @@
-import { Liquid } from '../../../src/liquid'
-
-describe('LiquidOptions#*keepOutputType*', function () {
-  it('should respect keepOutputType', async function () {
-    const engine = new Liquid({
-      keepOutputType: true
-    })
-    const context = {
-      'my-boolean': true,
-      'my-number': 42,
-      'my-string': 'test'
-    }
-    const booleanHtml = await engine.parseAndRender('{{my-boolean}}', context)
-    expect(booleanHtml).toBe(true)
-    const numberHtml = await engine.parseAndRender('{{my-number}}', context)
-    expect(numberHtml).toBe(42)
-    const html = await engine.parseAndRender('{{my-string}}', context)
-    expect(html).toBe('test')
-    const composedHtml = await engine.parseAndRender('{{my-string}}:{{my-number}}', context)
-    expect(composedHtml).toBe('test:42')
-  })
-
-  it('should respect keepOutputType = false as default', async function () {
-    const engine = new Liquid()
-    const context = {
-      'my-boolean': true,
-      'my-number': 42,
-      'my-string': 'test'
-    }
-    const booleanHtml = await engine.parseAndRender('{{my-boolean}}', context)
-    expect(booleanHtml).toBe('true')
-    const numberHtml = await engine.parseAndRender('{{my-number}}', context)
-    expect(numberHtml).toBe('42')
-    const html = await engine.parseAndRender('{{my-string}}', context)
-    expect(html).toBe('test')
-    const composedHtml = await engine.parseAndRender('{{my-string}}:{{my-number}}', context)
-    expect(composedHtml).toBe('test:42')
-  })
-})

test/integration/liquid/liquid.spec.ts

@@ -1,6 +1,7 @@
 import { Liquid, Context, isFalsy } from '../../../src'
 import { mock, restore } from '../../stub/mockfs'
 import { drainStream } from '../../stub/stream'
+import { ThrowingTag } from '../../stub/tags'
 import { resolve } from 'path'
 
 describe('Liquid', function () {
@@ -231,11 +232,7 @@ describe('Liquid', function () {
         '/root/error.html': 'A{%throwingTag%}B'
       })
       engine = new Liquid({ root: ['/root/'] })
-      engine.registerTag('throwingTag', {
-        render: function () {
-          throw new Error('intended render error')
-        }
-      })
+      engine.registerTag('throwingTag', ThrowingTag)
     })
     afterEach(restore)
     it('should render a simple value', async () => {
@@ -244,7 +241,7 @@ describe('Liquid', function () {
     })
     it('should throw RenderError when tag throws', async () => {
       const stream = await engine.renderFileToNodeStream('error.html')
-      expect(drainStream(stream)).rejects.toThrow(/intended render error/)
+      expect(drainStream(stream)).rejects.toThrow(/intended error/)
     })
   })
   describe('#analyze', () => {

test/integration/liquid/register-tags.spec.ts

@@ -1,38 +1,57 @@
 import { Liquid } from '../../../src/liquid'
+import { Tag } from '../../../src/template/tag'
+import type { Context } from '../../../src/context'
+import type { TagToken, TopLevelToken } from '../../../src/tokens'
 
 describe('liquid#registerTag()', function () {
   it('should support render to simple string', async () => {
+    class SimpleStringTag extends Tag {
+      render () {
+        return 'B'
+      }
+    }
     const liquid = new Liquid()
-    liquid.registerTag('simple-string', {
-      render: () => 'B'
-    })
+    liquid.registerTag('simple-string', SimpleStringTag)
     const html = await liquid.parseAndRender(`A{% simple-string %}C`)
     return expect(html).toBe('ABC')
   })
   it('should support async tag render', async () => {
+    class AsyncStringTag extends Tag {
+      async render () {
+        return 'B'
+      }
+    }
     const liquid = new Liquid()
-    liquid.registerTag('async-string', {
-      render: async () => 'B'
-    })
+    liquid.registerTag('async-string', AsyncStringTag)
     const html = await liquid.parseAndRender(`A{% async-string %}C`)
     return expect(html).toBe('ABC')
   })
   it('should have access to ctx in render()', async () => {
+    class DynamicStringTag extends Tag {
+      async render (ctx: Context) {
+        return ctx.get(['c'])
+      }
+    }
     const liquid = new Liquid()
-    liquid.registerTag('dynamic-string', {
-      render: async (ctx) => ctx.get(['c'])
-    })
+    liquid.registerTag('dynamic-string', DynamicStringTag)
     const html = await liquid.parseAndRender(`A{% dynamic-string %}C`, {
       c: 'B'
     })
     return expect(html).toBe('ABC')
   })
   it('should have access to tag arguments', async () => {
+    class ArgumentReflectorTag extends Tag {
+      variable: string
+      constructor (token: TagToken, remainTokens: TopLevelToken[], liquid: Liquid) {
+        super(token, remainTokens, liquid)
+        this.variable = token.args.split('=')[1]
+      }
+      async render (ctx: Context) {
+        return ctx.get([this.variable])
+      }
+    }
     const liquid = new Liquid()
-    liquid.registerTag('argument-reflector', {
-      parse: function (token) { this.variable = token.args.split('=')[1] },
-      render: async function (ctx) { return ctx.get(this.variable) }
-    })
+    liquid.registerTag('argument-reflector', ArgumentReflectorTag)
     const html = await liquid.parseAndRender(`A{% argument-reflector variable=c %}C`, {
       c: 'B'
     })

test/integration/liquid/scope-security.spec.ts

@@ -0,0 +1,61 @@
+import { Liquid } from '../../../src/liquid'
+import { Drop } from '../../../src/drop/drop'
+
+describe('scope security', function () {
+  let liquid: Liquid
+
+  beforeEach(function () {
+    liquid = new Liquid()
+  })
+
+  it('should iterate plain objects via inherited Symbol.iterator (ownPropertyOnly exception)', async function () {
+    // eslint-disable-next-line no-extend-native
+    (Object.prototype as any)[Symbol.iterator] = function * () { yield 'inherited' }
+    try {
+      await expect(liquid.parseAndRender(
+        '{% for x in obj %}{{ x }}{% endfor %}',
+        { obj: {} }
+      )).resolves.toBe('inherited')
+    } finally {
+      delete (Object.prototype as any)[Symbol.iterator]
+    }
+  })
+
+  it('should not read inherited size on plain objects', async function () {
+    const obj = Object.create({ size: 99 })
+    obj.own = 'yes'
+    await expect(liquid.parseAndRender('{{ obj.size }}', { obj })).resolves.toBe('1')
+  })
+
+  it('should read inherited size when ownPropertyOnly=false', async function () {
+    liquid = new Liquid({ ownPropertyOnly: false })
+    const obj = Object.create({ size: 99 })
+    await expect(liquid.parseAndRender('{{ obj.size }}', { obj })).resolves.toBe('99')
+  })
+
+  it('should still iterate Drop with Symbol.iterator', async function () {
+    class IterableDrop extends Drop {
+      * [Symbol.iterator] () {
+        yield 'a'
+        yield 'b'
+      }
+    }
+    await expect(liquid.parseAndRender(
+      '{% for x in drop %}{{ x }}{% endfor %}',
+      { drop: new IterableDrop() }
+    )).resolves.toBe('ab')
+  })
+
+  it('should block own blocked keys when ownPropertyOnly=true', async function () {
+    const scope = JSON.parse('{"__proto__": {"polluted": true}, "constructor": {"name": "Custom"}, "name": "Alice"}')
+    await expect(liquid.parseAndRender('{{ __proto__.polluted }}', scope)).resolves.toBe('')
+    await expect(liquid.parseAndRender('{{ constructor.name }}', scope)).resolves.toBe('')
+    await expect(liquid.parseAndRender('{{ name }}', scope)).resolves.toBe('Alice')
+  })
+
+  it('should block inherited properties when ownPropertyOnly=true', async function () {
+    const scope = { foo: Object.create({ __proto__: { bar: 'BAR' }, constructor: { name: 'Evil' } }) }
+    await expect(liquid.parseAndRender('{{ foo.__proto__ }}', scope)).resolves.toBe('')
+    await expect(liquid.parseAndRender('{{ foo.constructor }}', scope)).resolves.toBe('')
+  })
+})

test/integration/misc/error.spec.ts

@@ -2,7 +2,8 @@ import { RenderError } from '../../../src/util/error'
 import { Liquid } from '../../../src/liquid'
 import { resolve } from 'path'
 import { mock, restore } from '../../stub/mockfs'
-import { throwIntendedError, rejectIntendedError } from '../../stub/util'
+import { throwIntendedError } from '../../stub/util'
+import { ThrowingTag, RejectingTag, ThrowsOnParseTag } from '../../stub/tags'
 
 const strictEngine = new Liquid({
   strictVariables: true,
@@ -13,9 +14,9 @@ const strictCatchingEngine = new Liquid({
   strictVariables: true,
   strictFilters: true
 })
-strictEngine.registerTag('throwingTag', { render: throwIntendedError })
+strictEngine.registerTag('throwingTag', ThrowingTag)
 strictEngine.registerFilter('throwingFilter', throwIntendedError)
-strictCatchingEngine.registerTag('throwingTag', { render: throwIntendedError })
+strictCatchingEngine.registerTag('throwingTag', ThrowingTag)
 strictCatchingEngine.registerFilter('throwingFilter', throwIntendedError)
 
 describe('error', function () {
@@ -83,8 +84,8 @@ describe('error', function () {
       engine = new Liquid({
         root: '/'
       })
-      engine.registerTag('throwingTag', { render: throwIntendedError })
-      engine.registerTag('rejectingTag', { render: rejectIntendedError })
+      engine.registerTag('throwingTag', ThrowingTag)
+      engine.registerTag('rejectingTag', RejectingTag)
       engine.registerFilter('throwingFilter', throwIntendedError)
     })
     it('should throw RenderError when tag throws', async function () {
@@ -244,10 +245,7 @@ describe('error', function () {
     let engine: Liquid
     beforeEach(function () {
       engine = new Liquid()
-      engine.registerTag('throwsOnParse', {
-        parse: throwIntendedError,
-        render: () => ''
-      })
+      engine.registerTag('throwsOnParse', ThrowsOnParseTag)
     })
     it('should throw ParseError when filter not defined', async function () {
       await expect(strictEngine.parseAndRender('{{1 | a}}')).rejects.toMatchObject({
@@ -337,11 +335,7 @@ describe('error', function () {
       engine = new Liquid({
         root: '/'
       })
-      engine.registerTag('throwingTag', {
-        render: function () {
-          throw new Error('intended error')
-        }
-      })
+      engine.registerTag('throwingTag', ThrowingTag)
     })
     it('should throw RenderError when tag throws', function () {
       const src = '{%throwingTag%}'

test/integration/tags/for.spec.ts

@@ -7,9 +7,6 @@ describe('tags/for', function () {
   let liquid: Liquid, scope: Scope
   beforeEach(function () {
     liquid = new Liquid()
-    liquid.registerTag('throwingTag', {
-      render: function () { throw new Error('intended render error') }
-    })
     scope = {
       one: 1,
       // eslint-disable-next-line
@@ -123,6 +120,18 @@ describe('tags/for', function () {
       const html = await liquid.parseAndRender(src, scope)
       return expect(html).toBe('b')
     })
+
+    it('should goto else when limit empties collection', async function () {
+      const src = '{%for c in alpha limit:0%}a{%else%}b{%endfor%}'
+      const html = await liquid.parseAndRender(src, scope)
+      return expect(html).toBe('b')
+    })
+
+    it('should goto else when offset past end', async function () {
+      const src = '{%for c in alpha offset:10%}a{%else%}b{%endfor%}'
+      const html = await liquid.parseAndRender(src, scope)
+      return expect(html).toBe('b')
+    })
   })
 
   it('should support for with forloop', async function () {

test/stub/tags.ts

@@ -0,0 +1,26 @@
+import { throwIntendedError, rejectIntendedError } from './util'
+import { Tag } from '../../src/template/tag'
+import type { TagToken, TopLevelToken } from '../../src/tokens'
+import type { Liquid } from '../../src/liquid'
+
+export class ThrowingTag extends Tag {
+  render () {
+    throwIntendedError()
+  }
+}
+
+export class RejectingTag extends Tag {
+  async render () {
+    await rejectIntendedError()
+  }
+}
+
+export class ThrowsOnParseTag extends Tag {
+  constructor (token: TagToken, remainTokens: TopLevelToken[], liquid: Liquid) {
+    super(token, remainTokens, liquid)
+    throwIntendedError()
+  }
+  render () {
+    return ''
+  }
+}

tsconfig.json

@@ -1,8 +1,9 @@
 {
   "compilerOptions": {
-    "target": "es6",
-    "module":"CommonJS",
-    "lib": ["es2015", "es2016", "es2017", "dom"],
+    "target": "ES2020",
+    "module":"ES2020",
+    "lib": ["ES2020", "dom"],
+    "moduleResolution": "node",
     "sourceMap": true,
     "outDir": "dist",
     "declaration": true,