replace handlebars with squirrelly (#5521)

* WIP: rip out handlebars and implement with squirrelly

- handle caching ourselves
- TODO: add tests, make sure escaping and all that jazz works

* fixes squirrelly template handling

* only fire mocha events when in run mode

* add unit tests for template engine rendering + caching

packages/driver/test/cypress/integration/e2e/rerun_spec.coffee

@@ -7,6 +7,8 @@
 window.top.hasRunOnce ?= false
 window.top.previousHash ?= window.top.location.hash
 
+isTextTerminal = Cypress.config("isTextTerminal")
+
 describe "rerun state bugs", ->
   it "stores viewport globally and does not hang on re-runs", ->
     ## NOTE: there's probably other ways to cause a re-run
@@ -28,8 +30,8 @@ describe "rerun state bugs", ->
       else
         if window.top.location.hash is window.top.previousHash
           ## 3rd time around
-          ## let the mocha end events fire
-          Cypress.config("isTextTerminal", true)
+          ## let the mocha end events fire if they're supposed to
+          Cypress.config("isTextTerminal", isTextTerminal)
         else
           ## our test has already run so remove
           ## the query param

packages/runner/static/index.html

@@ -17,7 +17,7 @@
       window.__Cypress__ = true
 
       setTimeout(function(){
-        Runner.start(document.getElementById('app'), "{{{base64Config}}}")
+        Runner.start(document.getElementById('app'), "{{base64Config | safe}}")
       }, 0)
     </script>
   </body>

packages/server/lib/html/iframe.html

@@ -17,12 +17,12 @@
       })(window.opener || window.parent);
     </script>
 
-    {{#each javascripts}}
-      <script type="text/javascript" src="{{{this}}}"></script>
+    {{each(options.javascripts)}}
+      <script type="text/javascript" src="{{@this}}"></script>
     {{/each}}
 
-    {{#each specs}}
-      <script type="text/javascript" src="{{{this}}}"></script>
+    {{each(options.specs)}}
+      <script type="text/javascript" src="{{@this}}"></script>
     {{/each}}
   </body>
 </html>

packages/server/lib/server.coffee

@@ -1,5 +1,4 @@
 _            = require("lodash")
-exphbs       = require("express-handlebars")
 url          = require("url")
 http         = require("http")
 concatStream = require("concat-stream")
@@ -31,6 +30,7 @@ logger       = require("./logger")
 Socket       = require("./socket")
 Request      = require("./request")
 fileServer   = require("./file_server")
+templateEngine = require("./template_engine")
 
 DEFAULT_DOMAIN_NAME    = "localhost"
 fullyQualifiedRe       = /^https?:\/\//
@@ -85,11 +85,7 @@ class Server
 
     ## since we use absolute paths, configure express-handlebars to not automatically find layouts
     ## https://github.com/cypress-io/cypress/issues/2891
-    app.engine("html", exphbs({
-      defaultLayout: false
-      layoutsDir: []
-      partialsDir: []
-    }))
+    app.engine("html", templateEngine.render)
 
     ## handle the proxied url in case
     ## we have not yet started our websocket server

packages/server/lib/template_engine.js

@@ -0,0 +1,29 @@
+const Sqrl = require('squirrelly')
+const fs = require('./util/fs')
+
+const cache = {}
+
+module.exports = {
+  cache,
+
+  render (filePath, options, cb) {
+    const cachedFn = cache[filePath]
+
+    // if we already have a cachedFn function
+    if (cachedFn) {
+      // just return it and move in
+      return cb(null, cachedFn(options, Sqrl))
+    }
+
+    // else go read it off the filesystem
+    return fs
+    .readFileAsync(filePath, 'utf8')
+    .then((str) => {
+      // and cache the Sqrl compiled template fn
+      const compiledFn = cache[filePath] = Sqrl.Compile(str)
+
+      return compiledFn(options, Sqrl)
+    })
+    .asCallback(cb)
+  },
+}

packages/server/package.json

@@ -72,7 +72,6 @@
     "evil-dns": "0.2.0",
     "execa": "1.0.0",
     "express": "4.16.4",
-    "express-handlebars": "3.0.2",
     "find-process": "1.4.1",
     "fix-path": "2.1.0",
     "fluent-ffmpeg": "2.1.2",
@@ -125,6 +124,7 @@
     "shell-env": "3.0.0",
     "signal-exit": "3.0.2",
     "sinon": "5.1.1",
+    "squirrelly": "7.7.0",
     "strip-ansi": "3.0.1",
     "syntax-error": "1.4.0",
     "term-size": "2.1.0",

packages/server/test/unit/template_engine_spec.js

@@ -0,0 +1,53 @@
+require('../spec_helper')
+
+const os = require('os')
+const path = require('path')
+const Bluebird = require('bluebird')
+const { cache, render } = require('../../lib/template_engine')
+const fs = require('../../lib/util/fs')
+
+describe('lib/template_engine', () => {
+  it('renders and caches a template function', () => {
+    sinon.spy(fs, 'readFile')
+
+    expect(cache).to.deep.eq({})
+
+    const tmpPath = path.join(os.tmpdir(), 'index.html')
+
+    return fs
+    .writeFileAsync(tmpPath, 'My favorite template engine is {{favorite}}.')
+    .then(() => {
+      return Bluebird.fromCallback((cb) => {
+        const opts = {
+          favorite: 'Squirrelly',
+        }
+
+        return render(tmpPath, opts, cb)
+      })
+    })
+    .then((str) => {
+      expect(str).to.eq('My favorite template engine is Squirrelly.')
+
+      expect(fs.readFile).to.be.calledOnce
+
+      const compiledFn = cache[tmpPath]
+
+      expect(compiledFn).to.be.a('function')
+
+      return Bluebird.fromCallback((cb) => {
+        const opts = {
+          favorite: 'Squirrelly2',
+        }
+
+        return render(tmpPath, opts, cb)
+      })
+      .then((str) => {
+        expect(str).to.eq('My favorite template engine is Squirrelly2.')
+
+        expect(cache[tmpPath]).to.eq(compiledFn)
+
+        expect(fs.readFile).to.be.calledOnce
+      })
+    })
+  })
+})