Merge pull request #65 from GoogleChrome/misc

misc fixes

README.md

@@ -2,7 +2,7 @@
 
 This is a polyfill for the `Proxy` object, part of ES6.
 See the [MDN docs](https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Proxy) or [Introducing ES2015 Proxies](https://developers.google.com/web/updates/2016/02/es2015-proxies) for more information on `Proxy` itself.
-Unlike other polyfills, this does not require `Object.observe`, [which is deprecated](https://www.google.com/search?q=object.observe+deprecated).
+Unlike other polyfills, this does not require `Object.observe`, [which is no longer supported anywhere](https://www.google.com/search?q=object.observe+deprecated).
 
 The polyfill supports just a limited number of proxy 'traps'.
 It also works by calling [seal](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/seal) on the object passed to `Proxy`.
@@ -69,10 +69,10 @@ function observe(o, callback) {
   return buildProxy('', o);
 }
 
-const x = {'model': {name: 'Falcon'}};
+const x = {'model': {name: 'LEAF'}};
 const p = observe(x, (property, value) => console.info(property, value));
-p.model.name = 'Commodore';
-// model.name Commodore
+p.model.name = 'Tesla';
+// model.name Tesla
 ```
 
 ## Adding new properties
@@ -94,48 +94,34 @@ For a similar reason, this polyfill can't proxy `Array` objects very well - but
 
 # Usage
 
-## To assign Proxy to the global object
+Install via your favourite package manager as `proxy-polyfill`.
 
-Include the JavaScript at the start of your page, as an ES6 module (although browsers that support ES6 modules support `Proxy` natively) or include it as a dependency to your build steps.
-The source is in ES6, but the included, minified version is ES5.
+## To polyfill Proxy everywhere
 
-## To consume Proxy as a function
+You should include `proxy-polyfill` into your build system (just require it directly, it doesn't export anything), or import the `proxy.min.js` file directly.
+This is the recommended approach and works on the web, in Node, or React Native.
 
-Require from your app the file `./src/proxy.js`, which exports a proxy polyfill functionvian commonJS.
+## To consume the polyfill as a function
+
+Requires `./src/proxy.js`, which exports a proxy polyfill _builder_ function in commonJS.
 
 ```js
 // commonJS require
-const ProxyPolyfill = require('proxy-polyfill/src/proxy');
+const proxyPolyfill = require('proxy-polyfill/src/proxy')();
 
 // Your environment may also support transparent rewriting of commonJS to ES6:
-import ProxyPolyfill from 'proxy-polyfill/src/proxy';
+import ProxyPolyfillBuilder from 'proxy-polyfill/src/proxy';
+const proxyPolyfill = ProxyPolyfillBuilder();
 
 // Then use...
-const myProxy = new ProxyPolyfill(...);
-```
-
-## Installation
-
-Available via NPM or Bower-
-
-```bash
-$ npm install proxy-polyfill
-$ bower install proxy-polyfill
+const myProxy = new proxyPolyfill(...);
 ```
 
-If this is imported as a Node module, it will polyfill the global namespace rather than returning the `Proxy` object.
-If you'd like to just get the polyfill'ed version, use the require statement as above.
-
-## Supports
+# Support
 
 The polyfill supports browsers that implement the full [ES5 spec](http://kangax.github.io/compat-table/es5/), such as IE9+ and Safari 6+.
 It may work in other non-browser environments too.
 
 Note that Firefox, Chrome, Safari 10+ and Edge support `Proxy` natively.
+You don't need this if you're only targeting these modern browsers.
 
-# Release
-
-Run
-```bash
-$ npm run build
-```

build.js

@@ -23,10 +23,9 @@ const closureCompiler = new ClosureCompiler({
   language_in: 'ECMASCRIPT6_STRICT',
   language_out: 'ECMASCRIPT5',
   compilation_level: 'ADVANCED_OPTIMIZATIONS',
-//  dependency_mode: 'STRICT',
   warning_level: 'VERBOSE',
   process_common_js_modules: true,
-  output_wrapper: '(function(){%output%})()', // this prevents closure compiler from polluting the global scope
+  output_wrapper: '(function(){%output%})();',  // don't pollute global scope
 });
 
 const compilerProcess = closureCompiler.run((code, stdout, stderr) => {

src/proxy.js

@@ -41,10 +41,15 @@ module.exports = function proxyPolyfill() {
     // to call itself, but that seems unlikely especially when using the polyfill.
     let throwRevoked = function() {};
     lastRevokeFn = function() {
+      /** @suppress {checkTypes} */
+      target = null;  // clear ref
       throwRevoked = function(trap) {
         throw new TypeError(`Cannot perform '${trap}' on a proxy that has been revoked`);
       };
     };
+    setTimeout(function() {
+      lastRevokeFn = null;
+    }, 0);
 
     // Fail on unsupported traps: Chrome doesn't do this, but ensure that users of the polyfill
     // are a bit more careful. Copy the internal parts of handler to prevent user changes.