[ES6 modules] Introduce ModuleMap

third_party/WebKit/Source/core/dom/ModuleMap.h

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef ModuleMap_h
+#define ModuleMap_h
+
+#include "core/CoreExport.h"
+#include "platform/heap/Handle.h"
+#include "platform/weborigin/KURL.h"
+#include "platform/weborigin/KURLHash.h"
+#include "wtf/HashMap.h"
+
+namespace blink {
+
+class Modulator;
+class ModuleScript;
+class ModuleScriptFetchRequest;
+class SingleModuleClient;
+enum class ModuleGraphLevel;
+
+// A ModuleMap implements "module map" spec.
+// https://html.spec.whatwg.org/#module-map
+class CORE_EXPORT ModuleMap final : public GarbageCollected<ModuleMap> {
+  WTF_MAKE_NONCOPYABLE(ModuleMap);
+  class Entry;
+  class LoaderHost;
+
+ public:
+  static ModuleMap* create(Modulator* modulator) {
+    return new ModuleMap(modulator);
+  }
+  DECLARE_TRACE();
+
+  // https://html.spec.whatwg.org/multipage/webappapis.html#fetch-a-single-module-script
+  void fetchSingleModuleScript(const ModuleScriptFetchRequest&,
+                               ModuleGraphLevel,
+                               SingleModuleClient*);
+
+  // Synchronously get the ModuleScript for a given URL.
+  // Note: fetchSingleModuleScript of the ModuleScript must be complete before
+  // calling this.
+  ModuleScript* getFetchedModuleScript(const KURL&) const;
+
+  Modulator* modulator() { return m_modulator; }
+
+ private:
+  explicit ModuleMap(Modulator*);
+
+  using MapImpl = HeapHashMap<KURL, Member<Entry>>;
+
+  // A module map is a map of absolute URLs to map entry.
+  MapImpl m_map;
+
+  Member<Modulator> m_modulator;
+};
+
+}  // namespace blink
+
+#endif