diff --git a/src/builtin/tags/case.ts b/src/builtin/tags/case.ts
index 4033ffc68..e8f4a20ad 100644
--- a/src/builtin/tags/case.ts
+++ b/src/builtin/tags/case.ts
@@ -16,13 +16,10 @@ export default {
 
         while (!tokenizer.end()) {
           const value = tokenizer.readValue()
-          if (value) {
-            this.cases.push({
-              val: value,
-              templates: p
-            })
-          }
-
+          this.cases.push({
+            val: value,
+            templates: p
+          })
           tokenizer.readTo(',')
         }
       })
diff --git a/src/builtin/tags/if.ts b/src/builtin/tags/if.ts
index 1cf06d3b0..5a600af59 100644
--- a/src/builtin/tags/if.ts
+++ b/src/builtin/tags/if.ts
@@ -1,4 +1,4 @@
-import { Value, Emitter, isTruthy, TagToken, TopLevelToken, Context, Template, TagImplOptions, ParseStream } from '../../types'
+import { Value, Emitter, isTruthy, TagToken, TopLevelToken, Context, Template, TagImplOptions } from '../../types'
 
 export default {
   parse: function (tagToken: TagToken, remainTokens: TopLevelToken[]) {
@@ -6,34 +6,29 @@ export default {
     this.elseTemplates = []
 
     let p
-    const stream: ParseStream = this.liquid.parser.parseStream(remainTokens)
+    this.liquid.parser.parseStream(remainTokens)
       .on('start', () => this.branches.push({
-        cond: new Value(tagToken.args, this.liquid),
+        predicate: new Value(tagToken.args, this.liquid),
+        templates: (p = [])
+      }))
+      .on('tag:elsif', (token: TagToken) => this.branches.push({
+        predicate: new Value(token.args, this.liquid),
         templates: (p = [])
       }))
-      .on('tag:elsif', (token: TagToken) => {
-        this.branches.push({
-          cond: new Value(token.args, this.liquid),
-          templates: p = []
-        })
-      })
       .on('tag:else', () => (p = this.elseTemplates))
-      .on('tag:endif', () => stream.stop())
+      .on('tag:endif', function () { this.stop() })
       .on('template', (tpl: Template) => p.push(tpl))
-      .on('end', () => {
-        throw new Error(`tag ${tagToken.getText()} not closed`)
-      })
-
-    stream.start()
+      .on('end', () => { throw new Error(`tag ${tagToken.getText()} not closed`) })
+      .start()
   },
 
   render: function * (ctx: Context, emitter: Emitter) {
     const r = this.liquid.renderer
 
-    for (const branch of this.branches) {
-      const cond = yield branch.cond.value(ctx, ctx.opts.lenientIf)
-      if (isTruthy(cond, ctx)) {
-        yield r.renderTemplates(branch.templates, ctx, emitter)
+    for (const { predicate, templates } of this.branches) {
+      const value = yield predicate.value(ctx, ctx.opts.lenientIf)
+      if (isTruthy(value, ctx)) {
+        yield r.renderTemplates(templates, ctx, emitter)
         return
       }
     }
diff --git a/src/builtin/tags/render.ts b/src/builtin/tags/render.ts
index e281d66f7..3b90a0459 100644
--- a/src/builtin/tags/render.ts
+++ b/src/builtin/tags/render.ts
@@ -18,8 +18,10 @@ export default {
       const keyword = tokenizer.readIdentifier()
       if (keyword.content === 'with' || keyword.content === 'for') {
         tokenizer.skipBlank()
+        // can be normal key/value pair, like "with: true"
         if (tokenizer.peek() !== ':') {
           const value = tokenizer.readValue()
+          // can be normal key, like "with,"
           if (value) {
             const beforeAs = tokenizer.p
             const asStr = tokenizer.readIdentifier()
@@ -30,10 +32,14 @@ export default {
             this[keyword.content] = { value, alias: alias && alias.content }
             tokenizer.skipBlank()
             if (tokenizer.peek() === ',') tokenizer.advance()
+            // matched!
             continue
           }
         }
       }
+      /**
+       * restore cursor if with/for not matched
+       */
       tokenizer.p = begin
       break
     }
@@ -83,14 +89,11 @@ export function parseFilePath (tokenizer: Tokenizer, liquid: Liquid): ParsedFile
     const file = tokenizer.readValue()
     if (file === undefined) throw new TypeError(`illegal argument "${tokenizer.input}"`)
     if (file.getText() === 'none') return null
-    // for filenames like "files/{{file}}", eval as liquid template
     if (TypeGuards.isQuotedToken(file)) {
+      // for filenames like "files/{{file}}", eval as liquid template
       const tpls = liquid.parse(evalQuotedToken(file))
       // for filenames like "files/file.liquid", extract the string directly
-      if (tpls.length === 1) {
-        const first = tpls[0]
-        if (TypeGuards.isHTMLToken(first)) return first.getText()
-      }
+      if (tpls.length === 1 && TypeGuards.isHTMLToken(tpls[0].token)) return tpls[0].token.getContent()
       return tpls
     }
     return file
diff --git a/src/builtin/tags/unless.ts b/src/builtin/tags/unless.ts
index 442a75827..54ed7d63e 100644
--- a/src/builtin/tags/unless.ts
+++ b/src/builtin/tags/unless.ts
@@ -1,45 +1,35 @@
-import { Value, TopLevelToken, Template, Emitter, isTruthy, isFalsy, ParseStream, Context, TagImplOptions, TagToken } from '../../types'
+import { Value, TopLevelToken, Template, Emitter, isTruthy, isFalsy, Context, TagImplOptions, TagToken } from '../../types'
 
 export default {
   parse: function (tagToken: TagToken, remainTokens: TopLevelToken[]) {
-    this.templates = []
     this.branches = []
     this.elseTemplates = []
     let p
-    const stream: ParseStream = this.liquid.parser.parseStream(remainTokens)
-      .on('start', () => {
-        p = this.templates
-        this.cond = new Value(tagToken.args, this.liquid)
-      })
-      .on('tag:elsif', (token: TagToken) => {
-        this.branches.push({
-          cond: new Value(token.args, this.liquid),
-          templates: p = []
-        })
-      })
+    this.liquid.parser.parseStream(remainTokens)
+      .on('start', () => this.branches.push({
+        predicate: new Value(tagToken.args, this.liquid),
+        test: isFalsy,
+        templates: (p = [])
+      }))
+      .on('tag:elsif', (token: TagToken) => this.branches.push({
+        predicate: new Value(token.args, this.liquid),
+        test: isTruthy,
+        templates: (p = [])
+      }))
       .on('tag:else', () => (p = this.elseTemplates))
-      .on('tag:endunless', () => stream.stop())
+      .on('tag:endunless', function () { this.stop() })
       .on('template', (tpl: Template) => p.push(tpl))
-      .on('end', () => {
-        throw new Error(`tag ${tagToken.getText()} not closed`)
-      })
-
-    stream.start()
+      .on('end', () => { throw new Error(`tag ${tagToken.getText()} not closed`) })
+      .start()
   },
 
   render: function * (ctx: Context, emitter: Emitter) {
     const r = this.liquid.renderer
-    const cond = yield this.cond.value(ctx, ctx.opts.lenientIf)
 
-    if (isFalsy(cond, ctx)) {
-      yield r.renderTemplates(this.templates, ctx, emitter)
-      return
-    }
-
-    for (const branch of this.branches) {
-      const cond = yield branch.cond.value(ctx, ctx.opts.lenientIf)
-      if (isTruthy(cond, ctx)) {
-        yield r.renderTemplates(branch.templates, ctx, emitter)
+    for (const { predicate, test, templates } of this.branches) {
+      const value = yield predicate.value(ctx, ctx.opts.lenientIf)
+      if (test(value, ctx)) {
+        yield r.renderTemplates(templates, ctx, emitter)
         return
       }
     }
diff --git a/src/parser/parse-stream.ts b/src/parser/parse-stream.ts
index 5c7833907..7543f2125 100644
--- a/src/parser/parse-stream.ts
+++ b/src/parser/parse-stream.ts
@@ -15,13 +15,13 @@ export class ParseStream<T extends Token = TopLevelToken> {
     this.tokens = tokens
     this.parseToken = parseToken
   }
-  public on<T2 extends Template | T | undefined> (name: string, cb: (arg: T2) => void): ParseStream<T> {
+  public on<T2 extends Template | T | undefined> (name: string, cb: (this: ParseStream, arg: T2) => void): ParseStream<T> {
     this.handlers[name] = cb
     return this
   }
   private trigger <T extends Token | Template> (event: string, arg?: T) {
     const h = this.handlers[event]
-    return h ? (h(arg), true) : false
+    return h ? (h.call(this, arg), true) : false
   }
   public start () {
     this.trigger('start')
diff --git a/test/integration/builtin/filters/date.ts b/test/integration/builtin/filters/date.ts
index 73d7a269d..bc50815b5 100644
--- a/test/integration/builtin/filters/date.ts
+++ b/test/integration/builtin/filters/date.ts
@@ -30,6 +30,9 @@ describe('filters/date', function () {
     it('should apply numeric timezone offset (+2.30)', function () {
       return test('{{ "1990-12-31T23:00:00+02:30" | date: "%Y-%m-%dT%H:%M:%S"}}', '1990-12-31T23:00:00', undefined, opts)
     })
+    it('should automatically work when timezone not specified', function () {
+      return test('{{ "1990-12-31T23:00:00" | date: "%Y-%m-%dT%H:%M:%S"}}', '1990-12-31T23:00:00', undefined, opts)
+    })
   })
   it('should render string as string if not valid', function () {
     return test('{{ "foo" | date: "%Y"}}', 'foo')
diff --git a/test/integration/builtin/tags/layout.ts b/test/integration/builtin/tags/layout.ts
index 4fbd21c4e..0be2d30a8 100644
--- a/test/integration/builtin/tags/layout.ts
+++ b/test/integration/builtin/tags/layout.ts
@@ -191,6 +191,15 @@ describe('tags/layout', function () {
       return expect(html).to.equal('blackA')
     })
 
+    it('should support none', async function () {
+      mock({
+        '/main.html': '{% layout none %}foo'
+      })
+      const staticLiquid = new Liquid({ root: '/', dynamicPartials: false })
+      const html = await staticLiquid.renderFile('/main.html')
+      return expect(html).to.equal('foo')
+    })
+
     it('should support subpaths', async function () {
       mock({
         '/foo/parent.html': '{{color}}{%block%}{%endblock%}',
diff --git a/test/integration/builtin/tags/render.ts b/test/integration/builtin/tags/render.ts
index d7314786a..e05ec7c0c 100644
--- a/test/integration/builtin/tags/render.ts
+++ b/test/integration/builtin/tags/render.ts
@@ -1,6 +1,8 @@
 import { Liquid, Drop } from '../../../../src/liquid'
-import { expect } from 'chai'
+import { expect, use } from 'chai'
 import { mock, restore } from '../../../stub/mockfs'
+import * as chaiAsPromised from 'chai-as-promised'
+use(chaiAsPromised)
 
 describe('tags/render', function () {
   let liquid: Liquid
@@ -93,6 +95,22 @@ describe('tags/render', function () {
     const html = await liquid.renderFile('with.html')
     expect(html).to.equal('color:red, shape:rect')
   })
+  it('should treat as normal key/value if followed by ":"', async () => {
+    mock({
+      '/with.html': '{% render "color" with: "foo" %}',
+      '/color.html': 'color:{{color}}, with:{{with}}'
+    })
+    const html = await liquid.renderFile('with.html')
+    expect(html).to.equal('color:, with:foo')
+  })
+  it('should treat as normal key if with value not specified', async () => {
+    mock({
+      '/with.html': '{% render "color" with, shape: "rect" %}',
+      '/color.html': 'color:{{color}}, with:{{with}}, shape:{{shape}}'
+    })
+    const html = await liquid.renderFile('with.html')
+    expect(html).to.equal('color:, with:true, shape:rect')
+  })
   it('should support with...as', async function () {
     mock({
       '/with.html': '{% render "color" with color as c %}',
@@ -271,7 +289,7 @@ describe('tags/render', function () {
       const html = liquid.renderFileSync('with.html')
       expect(html).to.equal('color:red, shape:rect')
     })
-    it('should support filename with extention', function () {
+    it('should support filename with extension', function () {
       mock({
         '/parent.html': 'X{% render child.html color:"red" %}Y',
         '/child.html': 'child with {{color}}'
diff --git a/test/integration/liquid/fs-option.ts b/test/integration/liquid/fs-option.ts
index be68f35ae..83b9ed9bf 100644
--- a/test/integration/liquid/fs-option.ts
+++ b/test/integration/liquid/fs-option.ts
@@ -1,5 +1,7 @@
-import { expect } from 'chai'
+import { expect, use } from 'chai'
 import { Liquid } from '../../../src/liquid'
+import * as chaiAsPromised from 'chai-as-promised'
+use(chaiAsPromised)
 
 describe('LiquidOptions#fs', function () {
   let engine: Liquid
@@ -31,4 +33,13 @@ describe('LiquidOptions#fs', function () {
     const html = engine.renderFileSync('notexist/foo')
     expect(html).to.equal('content for /root/files/fallback')
   })
+
+  it('should throw lookup failure if fallback not specified', function () {
+    const engine = new Liquid({
+      root: '/root/',
+      fs: { ...fs, fallback: undefined }
+    } as any)
+    return expect(engine.renderFile('notexist/foo'))
+      .to.be.rejectedWith('Failed to lookup')
+  })
 })
diff --git a/test/integration/liquid/liquid.ts b/test/integration/liquid/liquid.ts
index c48f49ba2..55bf67ded 100644
--- a/test/integration/liquid/liquid.ts
+++ b/test/integration/liquid/liquid.ts
@@ -130,4 +130,13 @@ describe('Liquid', function () {
         .to.throw(/Failed to lookup "\/not\/exist.html" in "\/boo,\/root\/"/)
     })
   })
+  describe('#enderToNodeStream', function () {
+    const engine = new Liquid()
+    it('should render a simple value', function (done) {
+      const stream = engine.renderToNodeStream(engine.parse('{{"foo"}}'))
+      let html = ''
+      stream.on('data', data => { html += data })
+      stream.on('end', () => { expect(html).to.equal('foo'); done() })
+    })
+  })
 })
diff --git a/test/unit/liquid-options.ts b/test/unit/liquid-options.ts
new file mode 100644
index 000000000..df4ace548
--- /dev/null
+++ b/test/unit/liquid-options.ts
@@ -0,0 +1,15 @@
+import { normalize } from '../../src/liquid-options'
+import { expect } from 'chai'
+
+describe('liquid-options', () => {
+  describe('.normalize()', () => {
+    it('should return plain object for empty input', () => {
+      const options = normalize()
+      expect(JSON.stringify(options)).to.equal('{}')
+    })
+    it('should set falsy cache to undefined', () => {
+      const options = normalize({ cache: false })
+      expect(JSON.stringify(options)).to.equal('{}')
+    })
+  })
+})