| // 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; |
| |
| // 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() { |
| done = true; |
| var mod = module[loadedModule]; |
| var lib = mod[name]; |
| // Install unproxied module and library in caller's context. |
| patch(mod, lib); |
| } |
| // The deferred library object. Note, the only legal operations on a Dart |
| // library object should be get (to read a top-level variable, method, or |
| // Class) or set (to write a top-level variable). |
| return new Proxy({}, { |
| get: function(o, p) { |
| if (!done) loadDeferred(); |
| return module[name][p]; |
| }, |
| set: function(o, p, value) { |
| if (!done) loadDeferred(); |
| module[name][p] = value; |
| return true; |
| }, |
| }); |
| }; |
| |
| class LibraryLoader { |
| |
| constructor(name, defaultValue, imports, loader) { |
| this._name = name; |
| this._library = defaultValue ? defaultValue : {}; |
| this._imports = imports; |
| this._loader = loader; |
| |
| // Cyclic import detection |
| this._state = LibraryLoader.NOT_LOADED; |
| } |
| |
| loadImports() { |
| let results = []; |
| for (let name of this._imports) { |
| let lib = libraries.get(name); |
| if (!lib) { |
| throwLibraryError('Library not available: ' + name); |
| } |
| results.push(lib.load()); |
| } |
| return results; |
| } |
| |
| load() { |
| // Check for cycles |
| if (this._state == LibraryLoader.LOADING) { |
| throwLibraryError('Circular dependence on library: ' |
| + this._name); |
| } else if (this._state >= LibraryLoader.READY) { |
| 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; |
| 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. |
| let done = false; |
| this._library = new Proxy(library, { |
| get: function(o, name) { |
| if (!done) { |
| done = true; |
| loader._loader.apply(null, args); |
| loader._loader = null; |
| } |
| return o[name]; |
| } |
| }); |
| } |
| |
| this._state = LibraryLoader.READY; |
| return this._library; |
| } |
| |
| stub() { |
| return this._library; |
| } |
| } |
| LibraryLoader.NOT_LOADED = 0; |
| LibraryLoader.LOADING = 1; |
| LibraryLoader.READY = 2; |
| |
| // Map from name to LibraryLoader |
| let libraries = new Map(); |
| dart_library.libraries = function() { return libraries.keys(); }; |
| dart_library.debuggerLibraries = function() { |
| var debuggerLibraries = []; |
| libraries.forEach(function (value, key, map) { |
| debuggerLibraries.push(value.load()); |
| }); |
| debuggerLibraries.__proto__ = null; |
| return debuggerLibraries; |
| }; |
| |
| function library(name, defaultValue, imports, loader) { |
| let result = libraries.get(name); |
| if (result) { |
| console.warn('Already loaded ' + name); |
| return result; |
| } |
| result = new LibraryLoader(name, defaultValue, imports, loader); |
| libraries.set(name, result); |
| return result; |
| } |
| dart_library.library = library; |
| |
| function import_(libraryName) { |
| bootstrap(); |
| let loader = libraries.get(libraryName); |
| // TODO(vsm): A user might call this directly from JS (as we do in tests). |
| // We may want a different error type. |
| if (!loader) throwLibraryError('Library not found: ' + libraryName); |
| return loader.load(); |
| } |
| dart_library.import = import_; |
| |
| var _currentIsolate = false; |
| |
| function start(moduleName, libraryName) { |
| if (libraryName == null) libraryName = moduleName; |
| let library = import_(moduleName)[libraryName]; |
| let dart_sdk = import_('dart_sdk'); |
| |
| if (!_currentIsolate) { |
| // Create isolate. |
| _currentIsolate = true; |
| dart_sdk._isolate_helper.startRootIsolate(() => {}, []); |
| } |
| |
| library.main(); |
| } |
| dart_library.start = start; |
| |
| let _bootstrapped = false; |
| function bootstrap() { |
| if (_bootstrapped) return; |
| _bootstrapped = true; |
| |
| // Force import of core. |
| var dart_sdk = import_('dart_sdk'); |
| |
| // This import is only needed for chrome debugging. We should provide an |
| // option to compile without it. |
| dart_sdk._debugger.registerDevtoolsFormatter(); |
| } |
| |
| })(dart_library); |
| } |