Implement <script nomodule>

third_party/WebKit/Source/core/dom/ScriptLoader.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights
  * reserved.
  * Copyright (C) 2008 Nikolas Zimmermann <zimmermann@kde.org>
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 141 matching lines @@
 }
 
 void ScriptLoader::DispatchLoadEvent() {
   element_->DispatchLoadEvent();
   SetHaveFiredLoadEvent(true);
 }
 
 bool ScriptLoader::IsValidScriptTypeAndLanguage(
     const String& type,
     const String& language,
+    bool nomodule,
     LegacyTypeSupport support_legacy_types) {
+  if (RuntimeEnabledFeatures::moduleScriptsEnabled()) {
+    if (type == "module")
+      return true;
+    // https://html.spec.whatwg.org/#prepare-a-script, Step 11.

[hiroshige, 2017/04/15 00:45:09]

IsValidScriptTypeAndLanguage() is called as Step 6 of prepare-a-script,
and thus Step 11 (nomodule) should be implemented separately, outside this
function. Probably something like static bool
ScriptLoader::CheckNoModule(ScriptType, bool noModule) (a bad name though)
should be implemented and called from PrepareScript() and preloader.

[Nate Chapin, 2017/04/19 20:28:27]

Added ScriptLoader::BlockForNoModule()

+    if (nomodule)
+      return false;
+  }
+
   // FIXME: isLegacySupportedJavaScriptLanguage() is not valid HTML5. It is used
   // here to maintain backwards compatibility with existing layout tests. The
   // specific violations are:
   // - Allowing type=javascript. type= should only support MIME types, such as
   //   text/javascript.
   // - Allowing a different set of languages for language= and type=. language=
   //   supports Javascript 1.1 and 1.4-1.6, but type= does not.
   if (type.IsEmpty()) {
     return language.IsEmpty() ||  // assume text/javascript.
            MIMETypeRegistry::IsSupportedJavaScriptMIMEType("text/" +
                                                            language) ||
            MIMETypeRegistry::IsLegacySupportedJavaScriptLanguage(language);
-  } else if (RuntimeEnabledFeatures::moduleScriptsEnabled() &&
-             type == "module") {
-    return true;
   } else if (MIMETypeRegistry::IsSupportedJavaScriptMIMEType(
                  type.StripWhiteSpace()) ||
              (support_legacy_types == kAllowLegacyTypeInTypeAttribute &&
               MIMETypeRegistry::IsLegacySupportedJavaScriptLanguage(type))) {
     return true;
   }
 
   return false;
 }
 
 bool ScriptLoader::IsScriptTypeSupported(
     LegacyTypeSupport support_legacy_types) const {
-  return IsValidScriptTypeAndLanguage(element_->TypeAttributeValue(),
-                                      element_->LanguageAttributeValue(),
-                                      support_legacy_types);
+  return IsValidScriptTypeAndLanguage(
+      element_->TypeAttributeValue(), element_->LanguageAttributeValue(),
+      element_->NomoduleAttributeValue(), support_legacy_types);
 }
 
 // https://html.spec.whatwg.org/#prepare-a-script
 bool ScriptLoader::PrepareScript(const TextPosition& script_start_position,
                                  LegacyTypeSupport support_legacy_types) {
   // 1. "If the script element is marked as having "already started", then
   //     abort these steps at this point. The script is not executed."
   if (already_started_)
     return false;
 
@@ skipping 578 matching lines @@
   //     then abort these steps at this point. The script is not executed.
   return DeprecatedEqualIgnoringCase(event_attribute, "onload") ||
          DeprecatedEqualIgnoringCase(event_attribute, "onload()");
 }
 
 String ScriptLoader::ScriptContent() const {
   return element_->TextFromChildren();
 }
 
 }  // namespace blink