Custom formatter cleanup Fix case where displaying a class constructor generated unreadable huge ou…

pkg/dev_compiler/lib/js/legacy/dart_library.js

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /* This file defines the module loader for the dart runtime.
 */
 var dart_library;
 if (!dart_library) {
 dart_library =
   typeof module != "undefined" && module.exports || {};
 
 (function (dart_library) {
   'use strict';
 
   /** Note that we cannot use dart_utils.throwInternalError from here. */
   function throwLibraryError(message) {
     throw Error(message);
   }
 
-  const dartLibraryName = Symbol('dartLibraryName');
-  dart_library.dartLibraryName = dartLibraryName;
-
   const libraryImports = Symbol('libraryImports');
   dart_library.libraryImports = libraryImports;
 
+  // We need to load this symbol from the dart-sdk once it is loaded.
+  let dartLibraryName = null;
+
   // Module support.  This is a simplified module system for Dart.
   // Longer term, we can easily migrate to an existing JS module system:
   // ES6, AMD, RequireJS, ....
 
   // Returns a proxy that delegates to the underlying loader.
   // This defers loading of a module until a library is actually used.
   const loadedModule = Symbol('loadedModule');
   dart_library.defer = function(module, name, patch) {
     let done = false;
     function loadDeferred() {
@@ skipping 52 matching lines @@
         return this._library;
       }
       this._state = LibraryLoader.LOADING;
 
       // Handle imports
       let args = this.loadImports();
 
       // Load the library
       let loader = this;
       let library = this._library;
-      library[dartLibraryName] = this._name;
+      if (dartLibraryName !== null) {
+        this._library[dartLibraryName] = this._name;

[vsm, 2017/02/21 14:33:00]

Can this be moved to code_generator.dart - _emitModule perhaps?  That would make
it less legacy specific.  `this._library` should be the main export object.

+      }
+
       library[libraryImports] = this._imports;
       library[loadedModule] = library;
       args.unshift(library);
 
       if (this._name == 'dart_sdk') {
         // Eagerly load the SDK.
         this._loader.apply(null, args);
         loader._loader = null;
       } else {
         // Load / parse other modules on demand.
@@ skipping 73 matching lines @@
   }
   dart_library.start = start;
 
   let _bootstrapped = false;
   function bootstrap() {
     if (_bootstrapped) return;
     _bootstrapped = true;
 
     // Force import of core.
     var dart_sdk = import_('dart_sdk');
+    dartLibraryName = dart_sdk.dart.dartLibraryName;
 
     // This import is only needed for chrome debugging. We should provide an
     // option to compile without it.
     dart_sdk._debugger.registerDevtoolsFormatter();
   }
 
 })(dart_library);
 }