[ES6 modules] Introduce ModuleMap

third_party/WebKit/Source/core/dom/ScriptModuleResolver.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 ScriptModuleResolver_h
+#define ScriptModuleResolver_h
+
+#include "bindings/core/v8/ExceptionState.h"
+#include "platform/heap/Handle.h"
+#include "wtf/text/WTFString.h"
+
+namespace blink {
+
+class ScriptModule;
+class ModuleScript;
+
+// The ScriptModuleResolver interface is used from V8 module bindings
+// when it need the ScriptModule's descendants.
+//
+// When a module writes import 'x', the module is called the referrer, 'x' is
+// the specifier, and the module identified by 'x' is the descendant.
+// ScriptModuleResolver, given a referrer and specifier, can look up the
+// descendant.
+class ScriptModuleResolver : public GarbageCollected<ScriptModuleResolver> {
+ public:
+  DEFINE_INLINE_VIRTUAL_TRACE() {}
+
+  // Notify the ScriptModuleResolver that a ModuleScript exists.
+  // This hook gives a chance for the resolver impl to populate module record
+  // identifier -> ModuleScript mapping entry.
+  virtual void registerModuleScript(ModuleScript*) = 0;
+
+  // Implements "Runtime Semantics: HostResolveImportedModule"
+  // https://tc39.github.io/ecma262/#sec-hostresolveimportedmodule
+  // This returns a null ScriptModule when an exception is thrown.
+  virtual ScriptModule resolve(const String& specifier,
+                               const ScriptModule& referrer,
+                               ExceptionState&) = 0;
+};
+
+}  // namespace blink
+
+#endif  // ScriptModuleResolver_h