fix: allow {%render%} to reassign argument, #404

.all-contributorsrc

@@ -441,6 +441,15 @@
       "contributions": [
         "doc"
       ]
+    },
+    {
+      "login": "AleksandrHovhannisyan",
+      "name": "Aleksandr Hovhannisyan",
+      "avatar_url": "https://avatars.githubusercontent.com/u/19352442?v=4",
+      "profile": "https://www.aleksandrhovhannisyan.com/",
+      "contributions": [
+        "code"
+      ]
     }
   ],
   "contributorsPerLine": 7,

README.md

@@ -112,6 +112,7 @@ Want to contribute? see [Contribution Guidelines][contribution]. Thanks goes to
     <td align="center"><a href="https://github.com/bglw"><img src="https://avatars.githubusercontent.com/u/40188355?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Liam Bigelow</b></sub></a><br /><a href="https://github.com/harttle/liquidjs/commits?author=bglw" title="Code">💻</a></td>
     <td align="center"><a href="https://about.me/jasonkurian"><img src="https://avatars.githubusercontent.com/u/2642545?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Jason Kurian</b></sub></a><br /><a href="https://github.com/harttle/liquidjs/commits?author=JaKXz" title="Documentation">📖</a></td>
     <td align="center"><a href="https://github.com/dphm"><img src="https://avatars.githubusercontent.com/u/1707217?v=4?s=100" width="100px;" alt=""/><br /><sub><b>d pham (they/them)</b></sub></a><br /><a href="https://github.com/harttle/liquidjs/commits?author=dphm" title="Documentation">📖</a></td>
+    <td align="center"><a href="https://www.aleksandrhovhannisyan.com/"><img src="https://avatars.githubusercontent.com/u/19352442?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Aleksandr Hovhannisyan</b></sub></a><br /><a href="https://github.com/harttle/liquidjs/commits?author=AleksandrHovhannisyan" title="Code">💻</a></td>
   </tr>
 </table>
 

src/builtin/tags/render.ts

@@ -1,3 +1,4 @@
+import { __assign } from 'tslib'
 import { assert } from '../../util/assert'
 import { ForloopDrop } from '../../drop/forloop-drop'
 import { toEnumerable } from '../../util/collection'
@@ -51,12 +52,12 @@ export default {
     assert(filepath, () => `illegal filename "${filepath}"`)
 
     const childCtx = new Context({}, ctx.opts, ctx.sync)
-    const scope = yield hash.render(ctx)
+    const scope = childCtx.bottom()
+    __assign(scope, yield hash.render(ctx))
     if (this['with']) {
       const { value, alias } = this['with']
       scope[alias || filepath] = evalToken(value, ctx)
     }
-    childCtx.push(scope)
 
     if (this['for']) {
       const { value, alias } = this['for']
@@ -67,7 +68,7 @@ export default {
         scope[alias] = item
         const templates = yield liquid._parsePartialFile(filepath, childCtx.sync, this['currentFile'])
         yield liquid.renderer.renderTemplates(templates, childCtx, emitter)
-        scope.forloop.next()
+        scope['forloop'].next()
       }
     } else {
       const templates = yield liquid._parsePartialFile(filepath, childCtx.sync, this['currentFile'])

src/context/context.ts

@@ -6,9 +6,21 @@ import { isArray, isNil, isString, isFunction, toLiquid } from '../util/undersco
 import { InternalUndefinedVariableError } from '../util/error'
 
 export class Context {
+  /**
+   * insert a Context-level empty scope,
+   * for tags like {% capture %} {% assign %} to operate
+   */
   private scopes: Scope[] = [{}]
   private registers = {}
+  /**
+   * user passed in scope
+   * {% increment %}, {% decrement %} changes this scope,
+   * whereas {% capture %}, {% assign %} only hide this scope
+   */
   public environments: Scope
+  /**
+   * global scope used as fallback for missing variables
+   */
   public globals: Scope
   public sync: boolean
   public opts: NormalizedFullOptions

src/liquid-options.ts

@@ -55,7 +55,7 @@ export interface LiquidOptions {
   greedy?: boolean;
   /** `fs` is used to override the default file-system module with a custom implementation. */
   fs?: FS;
-  /** the global environment passed down to all partial templates, i.e. templates included by `include`, `layout` and `render` tags. */
+  /** 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;

test/integration/builtin/tags/assign.ts

@@ -69,6 +69,11 @@ describe('tags/assign', function () {
     const html = await liquid.parseAndRender(src)
     return expect(html).to.equal('-6')
   })
+  it('should allow reassignment', async function () {
+    const src = '{% assign var = 1 %}{% assign var = 2 %}{{ var }}'
+    const html = await liquid.parseAndRender(src)
+    return expect(html).to.equal('2')
+  })
   describe('scope', function () {
     it('should read from parent scope', async function () {
       const src = '{%for a in (1..2)%}{{num}}{%endfor%}'

test/integration/builtin/tags/capture.ts

@@ -19,7 +19,7 @@ describe('tags/capture', function () {
     return expect(html).to.equal('A')
   })
 
-  it('should shading rather than overwriting', async function () {
+  it('should not change root scope', async function () {
     const src = '{% capture var %}10{% endcapture %}{{var}}'
     const ctx = { 'var': 20 }
     const html = await liquid.parseAndRender(src, ctx)

test/integration/builtin/tags/increment.ts

@@ -39,7 +39,7 @@ describe('tags/increment', function () {
     return expect(html).to.equal('012 10')
   })
 
-  it('should not shading capture', async function () {
+  it('should not hide capture', async function () {
     const src = '{% capture var %}10{% endcapture %}{% increment var %}{% increment var %}{% increment var %} {{var}}'
     const html = await liquid.parseAndRender(src)
     return expect(html).to.equal('012 10')

test/integration/builtin/tags/render.ts

@@ -86,6 +86,16 @@ describe('tags/render', function () {
     expect(html).to.equal('InParent: harttle InChild: ')
   })
 
+  it('should allow argument reassignment', async function () {
+    mock({
+      '/parent.html': '{% render child.html, color: "red" %}',
+      '/child.html': '{% assign color = "green" %}{{ color }}'
+    })
+    const staticLiquid = new Liquid({ dynamicPartials: false, root: '/' })
+    const html = await staticLiquid.renderFile('parent.html')
+    return expect(html).to.equal('green')
+  })
+
   it('should be able to access globals', async function () {
     liquid = new Liquid({ root: '/', extname: '.html', globals: { name: 'Harttle' } })
     mock({