Closure Compiler API minifier and unit test

JSMin preserves "/*!"

HISTORY.txt

@@ -1,6 +1,7 @@
 Minify Release History
 
 Version 2.1.4
+    * Option to minify JS with Closure Compiler API w/ JSMin failover
     * Cookie/bookmarklet-based debug mode. No HTML editing!
     * Allows 1 file to be missing w/o complete failure
     * Combine multiple groups and files in single URI

min/config.php

@@ -102,6 +102,18 @@ $min_serveOptions['bubbleCssImports'] = false;
 $min_serveOptions['maxAge'] = 1800;
 
 
+/**
+ * To use Google's Closure Compiler API (falling back to JSMin on failure),
+ * uncomment the following lines:
+ */
+/*function closureCompiler($js) {
+    require_once 'Minify/JS/ClosureCompiler.php';
+    return Minify_JS_ClosureCompiler::minify($js);
+}
+$min_serveOptions['minifiers']['application/x-javascript'] = 'closureCompiler';
+//*/
+
+
 /**
  * If you'd like to restrict the "f" option to files within/below
  * particular directories below DOCUMENT_ROOT, set this here.

min/lib/JSMin.php

@@ -308,7 +308,7 @@ class JSMin {
                     $this->get();
                     // if comment preserved by YUI Compressor
                     if (0 === strpos($comment, '!')) {
-                        return "\n/*" . substr($comment, 1) . "*/\n";
+                        return "\n/*!" . substr($comment, 1) . "*/\n";
                     }
                     // if IE conditional comment
                     if (preg_match('/^@(?:cc_on|if|elif|else|end)\\b/', $comment)) {

min/lib/Minify/JS/ClosureCompiler.php

@@ -0,0 +1,109 @@
+<?php
+/**
+ * Class Minify_JS_ClosureCompiler
+ * @package Minify
+ */
+
+/**
+ * Minify Javascript using Google's Closure Compiler API
+ *
+ * @link http://code.google.com/closure/compiler/
+ * @package Minify
+ * @author Stephen Clay <steve@mrclay.org>
+ */
+class Minify_JS_ClosureCompiler {
+    const URL = 'http://closure-compiler.appspot.com/compile';
+
+    /**
+     * Minify Javascript code via HTTP request to the Closure Compiler API
+     *
+     * @param string $js input code
+     * @param array $options unused at this point
+     * @return string
+     */
+    public static function minify($js, array $options = array())
+    {
+        $obj = new self($options);
+        return $obj->min($js);
+    }
+
+    /**
+     *
+     * @param array $options
+     *
+     * fallbackFunc : default array($this, 'fallback');
+     */
+    public function __construct(array $options = array())
+    {
+        $this->_fallbackFunc = isset($options['fallbackMinifier'])
+            ? $options['fallbackMinifier']
+            : array($this, '_fallback');
+    }
+
+    public function min($js)
+    {
+        $content = $this->_getPostContent($js);
+        $bytes = (function_exists('mb_strlen') && ((int)ini_get('mbstring.func_overload') & 2))
+            ? mb_strlen($content, '8bit')
+            : strlen($content);
+        if ($bytes > 200000) {
+            throw new Minify_JS_ClosureCompiler_Exception(
+                'POST content larger than 200000 bytes'
+            );
+        }
+        $response = $this->_getResponse($content);
+        if (preg_match('/^Error\(\d\d?\):/', $response)) {
+            if (is_callable($this->_fallbackFunc)) {
+                $response = "/* Received errors from Closure Compiler API:\n$response"
+                          . "\n(Using fallback minifier)\n*/\n";
+                $response .= call_user_func($this->_fallbackFunc, $js);
+            } else {
+                throw new Minify_JS_ClosureCompiler_Exception($response);
+            }
+        }
+        if ($response === '') {
+            $errors = $this->_getResponse($this->_getPostContent($js, true));
+            throw new Minify_JS_ClosureCompiler_Exception($errors);
+        }
+        return $response;
+    }
+    
+    protected $_fallbackFunc = null;
+
+    protected function _getResponse($content)
+    {
+        $contents = file_get_contents(self::URL, false, stream_context_create(array(
+            'http' => array(
+                'method' => 'POST',
+                'header' => 'Content-type: application/x-www-form-urlencoded',
+                'content' => $content,
+                'max_redirects' => 0,
+                'timeout' => 15,
+            )
+        )));
+        if (false === $contents) {
+            throw new Minify_JS_ClosureCompiler_Exception(
+               "No HTTP response from server"
+            );
+        }
+        return trim($contents);
+    }
+
+    protected function _getPostContent($js, $returnErrors = false)
+    {
+        return http_build_query(array(
+            'js_code' => $js,
+            'output_info' => ($returnErrors ? 'errors' : 'compiled_code'),
+            'output_format' => 'text',
+            'compilation_level' => 'SIMPLE_OPTIMIZATIONS'
+        ));
+    }
+
+    protected function _fallback($js)
+    {
+        require_once 'JSMin.php';
+        return JSMin::minify($js);
+    }
+}
+
+class Minify_JS_ClosureCompiler_Exception extends Exception {}

min_unit_tests/_test_files/js/before.min.js

@@ -1,10 +1,10 @@
-/* is.js
+/*! is.js
 
  (c) 2001 Douglas Crockford
  2001 June 3
 */
 var is={ie:navigator.appName=='Microsoft Internet Explorer',java:navigator.javaEnabled(),ns:navigator.appName=='Netscape',ua:navigator.userAgent.toLowerCase(),version:parseFloat(navigator.appVersion.substr(21))||parseFloat(navigator.appVersion),win:navigator.platform=='Win32'}
-/**
+/*!*
  * preserve this comment, too
  */
 is.mac=is.ua.indexOf('mac')>=0;if(is.ua.indexOf('opera')>=0){is.ie=is.ns=false;is.opera=true;}

min_unit_tests/test_Minify_JS_ClosureCompiler.php

@@ -0,0 +1,49 @@
+<?php
+require_once '_inc.php';
+
+require_once 'Minify/JS/ClosureCompiler.php';
+
+function test_Minify_JS_ClosureCompiler()
+{
+    global $thisDir;
+    
+    $src = "
+(function (window, undefined){
+    function addOne(input) {
+        return 1 + input;
+    }
+    window.addOne = addOne;
+    window.undefined = undefined;
+})(window);
+    ";
+    $minExpected = "(function(a,b){a.addOne=function(c){return 1+c};a.undefined=b})(window);";
+    $minOutput = Minify_JS_ClosureCompiler::minify($src);
+    if (false !== strpos($minOutput, 'Error(22): Too many compiles')) {
+        echo "!NOTE: Too many recent calls to Closure Compiler API to test.\n";
+        return;
+    }
+
+
+    $passed = assertTrue($minExpected == $minOutput, 'Minify_JS_ClosureCompiler : Overall');
+    if (__FILE__ === realpath($_SERVER['SCRIPT_FILENAME'])) {
+        echo "\n---Output: " .countBytes($minOutput). " bytes\n\n{$minOutput}\n\n";
+        echo "---Expected: " .countBytes($minExpected). " bytes\n\n{$minExpected}\n\n";
+        echo "---Source: " .countBytes($src). " bytes\n\n{$src}\n\n\n";
+    }
+
+    $src = "function blah({ return 'blah';} ";
+    $exc = null;
+    try {
+        $minOutput = Minify_JS_ClosureCompiler::minify($src);
+    } catch (Exception $e) {
+        $exc = $e;
+    }
+    $passed = assertTrue(
+        $exc instanceof Minify_JS_ClosureCompiler_Exception
+        , 'Minify_JS_ClosureCompiler : Throws Minify_JS_ClosureCompiler_Exception');
+    if (__FILE__ === realpath($_SERVER['SCRIPT_FILENAME'])) {
+        echo "\n---Message: " . var_export($exc->getMessage(), 1) . "\n\n\n";
+    }
+}
+
+test_Minify_JS_ClosureCompiler();

min_unit_tests/test_all.php

@@ -9,6 +9,7 @@ require 'test_Minify_Cache_Memcache.php';
 require 'test_Minify_Cache_ZendPlatform.php';
 require 'test_Minify_CSS.php';
 require 'test_Minify_CSS_UriRewriter.php';
+require 'test_Minify_JS_ClosureCompiler.php';
 require 'test_Minify_CommentPreserver.php';
 require 'test_Minify_HTML.php';
 require 'test_Minify_ImportProcessor.php';