Fix #1832: Browser compiler should run code using globally-scoped eval (#5047)

* Explicitly turn off minify mangling, because it was previously implicitly disabled by the existence of the `eval` call we’re about to remove

* Update babel-core

* Run browser-compiled scripts using window.eval rather than just eval, to use a clean scope (many times faster)

* Update output

* Fix browser-based test broken by #5028

* Update output

Cakefile

@@ -72,7 +72,7 @@ transpile = (code) ->
   # Exclude the `modules` plugin in order to not break the `}(this));`
   # at the end of the `build:browser` code block.
   presets.push ['env', {modules: no}] unless process.env.TRANSFORM is 'false'
-  presets.push 'minify' unless process.env.MINIFY is 'false'
+  presets.push ['minify', {mangle: no}] unless process.env.MINIFY is 'false'
   babelOptions =
     compact: process.env.MINIFY isnt 'false'
     presets: presets

docs/v2/test.html

@@ -148,6 +148,8 @@ diffOutput = (expectedOutput, actualOutput) ->
         ok yes
       else if e.toString().indexOf('[stdin]') is 0 # Handle comparing error messages
         ok err e
+      else if err instanceof RegExp
+        ok err.test e
       else
         eq e, err
     else

documentation/site/docs.coffee

@@ -143,7 +143,7 @@ $(document).ready ->
     else
       $(textareas[index]).val()
     js = "#{js}\nalert(#{unescape run});" unless run is yes
-    eval js
+    window.eval js
     gtag 'event', 'run_code',
       event_category: 'engagement'
       event_label: $(@).closest('[data-example]').data('example')

documentation/site/test.html

@@ -108,6 +108,8 @@ onFail = (description, fn, err) ->
         ok yes
       else if e.toString().indexOf('[stdin]') is 0 # Handle comparing error messages
         ok err e
+      else if err instanceof RegExp
+        ok err.test e
       else
         eq e, err
     else

lib/coffeescript/browser.js

@@ -9,14 +9,19 @@
 
   CoffeeScript = require('./coffeescript');
 
-  compile = CoffeeScript.compile;
+  ({compile} = CoffeeScript);
 
-  // Use standard JavaScript `eval` to eval code.
+  // Use `window.eval` to evaluate code, rather than just `eval`, to run the
+  // script in a clean global scope rather than inheriting the scope of the
+  // CoffeeScript compiler. (So that `cake test:browser` also works in Node,
+  // use either `window.eval` or `global.eval` as appropriate).
   CoffeeScript.eval = function(code, options = {}) {
+    var globalRoot;
     if (options.bare == null) {
       options.bare = true;
     }
-    return eval(compile(code, options));
+    globalRoot = typeof window !== "undefined" && window !== null ? window : global;
+    return globalRoot['eval'](compile(code, options));
   };
 
   // Running code does not provide access to this scope.

package-lock.json

@@ -167,9 +167,9 @@
       }
     },
     "babel-core": {
-      "version": "6.26.2",
-      "resolved": "https://registry.npmjs.org/babel-core/-/babel-core-6.26.2.tgz",
-      "integrity": "sha512-rFKFnHY8sbRSqja2O5eTx0z0Na5hukdtsFt7X9xdBFXMurrJ5YoY78Y/2/EuNZIaDQKEJSfxSMePfsymxt0CZg==",
+      "version": "6.26.3",
+      "resolved": "https://registry.npmjs.org/babel-core/-/babel-core-6.26.3.tgz",
+      "integrity": "sha512-6jyFLuDmeidKmUEb3NM+/yawG0M2bDZ9Z1qbZP59cyHLz8kYGKYwpJP0UwUKKUiTRNvxfLesJnTedqczP7cTDA==",
       "dev": true,
       "requires": {
         "babel-code-frame": "6.26.0",
@@ -1509,7 +1509,7 @@
       "integrity": "sha1-btAhFz4vy0htestFxgCahW9kcHE=",
       "dev": true,
       "requires": {
-        "babel-core": "6.26.2",
+        "babel-core": "6.26.3",
         "babel-runtime": "6.26.0",
         "core-js": "2.5.5",
         "home-or-tmp": "2.0.0",

package.json

@@ -39,7 +39,7 @@
     "url": "git://github.com/jashkenas/coffeescript.git"
   },
   "devDependencies": {
-    "babel-core": "~6.26.2",
+    "babel-core": "~6.26.3",
     "babel-preset-babili": "~0.1.4",
     "babel-preset-env": "~1.6.1",
     "babel-preset-minify": "^0.4.0",

src/browser.coffee

@@ -4,12 +4,16 @@
 # `text/coffeescript` script tags, source maps via data-URLs, and so on.
 
 CoffeeScript = require './coffeescript'
-compile = CoffeeScript.compile
+{ compile } = CoffeeScript
 
-# Use standard JavaScript `eval` to eval code.
+# Use `window.eval` to evaluate code, rather than just `eval`, to run the
+# script in a clean global scope rather than inheriting the scope of the
+# CoffeeScript compiler. (So that `cake test:browser` also works in Node,
+# use either `window.eval` or `global.eval` as appropriate).
 CoffeeScript.eval = (code, options = {}) ->
   options.bare ?= on
-  eval compile code, options
+  globalRoot = if window? then window else global
+  globalRoot['eval'] compile code, options
 
 # Running code does not provide access to this scope.
 CoffeeScript.run = (code, options = {}) ->