update goog.js using base.js from google-closure-library@20161201.0.0

flyover · Dec 22, 2016 · c3eb2a7 · c3eb2a7
1 parent b51ca2d
commit c3eb2a7
Showing 1 changed file with 130 additions and 39 deletions.
diff --git a/demo/goog.js b/demo/goog.js
@@ -1031,8 +1031,9 @@ if (goog.DEPENDENCIES_ENABLED) {
   goog.isDeferredModule_ = function(name) {
     var path = goog.getPathFromDeps_(name);
     var loadFlags = path && goog.dependencies_.loadFlags[path] || {};
+    var languageLevel = loadFlags['lang'] || 'es3';
     if (path && (loadFlags['module'] == 'goog' ||
-                 goog.needsTranspile_(loadFlags['lang']))) {
+                 goog.needsTranspile_(languageLevel))) {
       var abspath = goog.basePath + path;
       return (abspath) in goog.dependencies_.deferred;
     }
@@ -1187,16 +1188,17 @@ if (goog.DEPENDENCIES_ENABLED) {
             goog.writeScriptSrcNode_(src);
           }
         } else {
-          var state = " onreadystatechange='goog.onScriptLoad_(this, " +
-              ++goog.lastNonModuleScriptIndex_ + ")' ";
+          var state = ' onreadystatechange=\'goog.onScriptLoad_(this, ' +
+              ++goog.lastNonModuleScriptIndex_ + ')\' ';
           doc.write(
               '<script type="text/javascript" src="' + src + '"' + state +
               '></' +
               'script>');
         }
       } else {
         doc.write(
-            '<script type="text/javascript">' + opt_sourceText + '</' +
+            '<script type="text/javascript">' +
+            goog.protectScriptTag_(opt_sourceText) + '</' +
             'script>');
       }
       return true;
@@ -1205,6 +1207,17 @@ if (goog.DEPENDENCIES_ENABLED) {
     }
   };
 
+  /**
+   * Rewrites closing script tags in input to avoid ending an enclosing script
+   * tag.
+   *
+   * @param {string} str
+   * @return {string}
+   * @private
+   */
+  goog.protectScriptTag_ = function(str) {
+    return str.replace(/<\/(SCRIPT)/ig, '\\x3c\\$1');
+  };
 
   /**
    * Determines whether the given language needs to be transpiled.
@@ -1217,41 +1230,18 @@ if (goog.DEPENDENCIES_ENABLED) {
       return true;
     } else if (goog.TRANSPILE == 'never') {
       return false;
-    } else if (!goog.transpiledLanguages_) {
-      goog.transpiledLanguages_ = {'es5': true, 'es6': true, 'es6-impl': true};
-      /** @preserveTry */
-      try {
-        // Perform some quick conformance checks, to distinguish
-        // between browsers that support es5, or es6.
-
-        // Identify ES3-only browsers by their incorrect treatment of commas.
-        goog.transpiledLanguages_['es5'] = eval('[1,].length!=1');
-
-        // Test es6: [FF50 (?), Edge 14 (?), Chrome 50]
-        //   (a) default params (specifically shadowing locals),
-        //   (b) destructuring, (c) block-scoped functions,
-        //   (d) for-of (const), (e) new.target/Reflect.construct
-        var es6fullTest =
-            'class X{constructor(){if(new.target!=String)throw 1;this.x=42}}' +
-            'let q=Reflect.construct(X,[],String);if(q.x!=42||!(q instanceof ' +
-            'String))throw 1;for(const a of[2,3]){if(a==2)continue;function ' +
-            'f(z={a}){let a=0;return z.a}{function f(){return 0;}}return f()' +
-            '==3}';
-
-        if (eval('(()=>{"use strict";' + es6fullTest + '})()')) {
-          goog.transpiledLanguages_['es6'] = false;
-          // TODO(joeltine): Remove es6-impl references for http://31340605.
-          goog.transpiledLanguages_['es6-impl'] = false;
-        }
-      } catch (err) {
-      }
+    } else if (!goog.requiresTranspilation_) {
+      goog.requiresTranspilation_ = goog.createRequiresTranspilation_();
+    }
+    if (lang in goog.requiresTranspilation_) {
+      return goog.requiresTranspilation_[lang];
+    } else {
+      throw new Error('Unknown language mode: ' + lang);
     }
-    return !!goog.transpiledLanguages_[lang];
   };
 
-
   /** @private {?Object<string, boolean>} */
-  goog.transpiledLanguages_ = null;
+  goog.requiresTranspilation_ = null;
 
 
   /** @private {number} */
@@ -1340,7 +1330,8 @@ if (goog.DEPENDENCIES_ENABLED) {
       var path = scripts[i];
       if (path) {
         var loadFlags = deps.loadFlags[path] || {};
-        var needsTranspile = goog.needsTranspile_(loadFlags['lang']);
+        var languageLevel = loadFlags['lang'] || 'es3';
+        var needsTranspile = goog.needsTranspile_(languageLevel);
         if (loadFlags['module'] == 'goog' || needsTranspile) {
           goog.importProcessedScript_(
               goog.basePath + path, loadFlags['module'] == 'goog',
@@ -1563,7 +1554,20 @@ goog.transpile_ = function(code, path) {
       // need it, we're about to load and write the ES6 code synchronously,
       // so a normal script-tag load will be too slow.
       eval(transpilerCode + '\n//# sourceURL=' + transpilerPath);
-      // Note: transpile.js reassigns goog.global['$jscomp'] so pull it again.
+      // Even though the transpiler is optional, if $gwtExport is found, it's
+      // a sign the transpiler was loaded and the $jscomp.transpile *should*
+      // be there.
+      if (goog.global['$gwtExport'] && goog.global['$gwtExport']['$jscomp'] &&
+          !goog.global['$gwtExport']['$jscomp']['transpile']) {
+        throw new Error(
+            'The transpiler did not properly export the "transpile" ' +
+            'method. $gwtExport: ' + JSON.stringify(goog.global['$gwtExport']));
+      }
+      // transpile.js only exports a single $jscomp function, transpile. We
+      // grab just that and add it to the existing definition of $jscomp which
+      // contains the polyfills.
+      goog.global['$jscomp'].transpile =
+          goog.global['$gwtExport']['$jscomp']['transpile'];
       jscomp = goog.global['$jscomp'];
       transpile = jscomp.transpile;
     }
@@ -1970,7 +1974,9 @@ goog.bindJs_ = function(fn, selfObj, var_args) {
     };
 
   } else {
-    return function() { return fn.apply(selfObj, arguments); };
+    return function() {
+      return fn.apply(selfObj, arguments);
+    };
   }
 };
 
@@ -2210,7 +2216,9 @@ goog.getCssName = function(className, opt_modifier) {
     rename =
         goog.cssNameMappingStyle_ == 'BY_WHOLE' ? getMapping : renameByParts;
   } else {
-    rename = function(a) { return a; };
+    rename = function(a) {
+      return a;
+    };
   }
 
   var result =
@@ -2730,3 +2738,86 @@ goog.tagUnsealableClass = function(ctr) {
  * @const @private {string}
  */
 goog.UNSEALABLE_CONSTRUCTOR_PROPERTY_ = 'goog_defineClass_legacy_unsealable';
+
+
+/**
+ * Returns a newly created map from language mode string to a boolean
+ * indicating whether transpilation should be done for that mode.
+ *
+ * Guaranteed invariant:
+ * For any two modes, l1 and l2 where l2 is a newer mode than l1,
+ * `map[l1] == true` implies that `map[l2] == true`.
+ * @private
+ * @return {!Object<string, boolean>}
+ */
+goog.createRequiresTranspilation_ = function() {
+  var /** !Object<string, boolean> */ requiresTranspilation = {'es3': false};
+  var transpilationRequiredForAllLaterModes = false;
+
+  /**
+   * Adds an entry to requiresTranspliation for the given language mode.
+   *
+   * IMPORTANT: Calls must be made in order from oldest to newest language
+   * mode.
+   * @param {string} modeName
+   * @param {function(): boolean} isSupported Returns true if the JS engine
+   *     supports the given mode.
+   */
+  function addNewerLanguageTranspilationCheck(modeName, isSupported) {
+    if (transpilationRequiredForAllLaterModes) {
+      requiresTranspilation[modeName] = true;
+    } else if (isSupported()) {
+      requiresTranspilation[modeName] = false;
+    } else {
+      requiresTranspilation[modeName] = true;
+      transpilationRequiredForAllLaterModes = true;
+    }
+  }
+
+  /**
+   * Does the given code evaluate without syntax errors and return a truthy
+   * result?
+   */
+  function /** boolean */ evalCheck(/** string */ code) {
+    try {
+      return !!eval(code);
+    } catch (ignored) {
+      return false;
+    }
+  }
+
+  // Identify ES3-only browsers by their incorrect treatment of commas.
+  addNewerLanguageTranspilationCheck('es5', function() {
+    return evalCheck('[1,].length==1');
+  });
+  addNewerLanguageTranspilationCheck('es6', function() {
+    // Test es6: [FF50 (?), Edge 14 (?), Chrome 50]
+    //   (a) default params (specifically shadowing locals),
+    //   (b) destructuring, (c) block-scoped functions,
+    //   (d) for-of (const), (e) new.target/Reflect.construct
+    var es6fullTest =
+        'class X{constructor(){if(new.target!=String)throw 1;this.x=42}}' +
+        'let q=Reflect.construct(X,[],String);if(q.x!=42||!(q instanceof ' +
+        'String))throw 1;for(const a of[2,3]){if(a==2)continue;function ' +
+        'f(z={a}){let a=0;return z.a}{function f(){return 0;}}return f()' +
+        '==3}';
+
+    return evalCheck('(()=>{"use strict";' + es6fullTest + '})()');
+  });
+  // TODO(joeltine): Remove es6-impl references for b/31340605.
+  // Consider es6-impl (widely-implemented es6 features) to be supported
+  // whenever es6 is supported. Technically es6-impl is a lower level of
+  // support than es6, but we don't have tests specifically for it.
+  addNewerLanguageTranspilationCheck('es6-impl', function() {
+    return true;
+  });
+  // ** and **= are the only new features in 'es7'
+  addNewerLanguageTranspilationCheck('es7', function() {
+    return evalCheck('2 ** 2 == 4');
+  });
+  // async functions are the only new features in 'es8'
+  addNewerLanguageTranspilationCheck('es8', function() {
+    return evalCheck('async () => 1, true');
+  });
+  return requiresTranspilation;
+};