Bug 1839954 - support async defer and module scripts r=emilio

https://www.w3.org/2012/01/05-svg-irc#T21-07-03 says that async and defer should be supported as does the specification https://www.w3.org/TR/SVG2/interact.html#ScriptElement

w3c/svgwg#918 tracks getting the SVGScriptElement webidl updated.

Differential Revision: https://phabricator.services.mozilla.com/D181936

dom/base/Document.cpp

@@ -18114,12 +18114,12 @@ void Document::RecordNavigationTiming(ReadyState aReadyState) {
   }
 }
 
-bool Document::ModuleScriptsEnabled() {
+bool Document::ModuleScriptsEnabled() const {
   return nsContentUtils::IsChromeDoc(this) ||
          StaticPrefs::dom_moduleScripts_enabled();
 }
 
-bool Document::ImportMapsEnabled() {
+bool Document::ImportMapsEnabled() const {
   return nsContentUtils::IsChromeDoc(this) ||
          StaticPrefs::dom_importMaps_enabled();
 }

dom/base/Document.h

@@ -4029,9 +4029,9 @@ class Document : public nsINode,
 
   mozilla::dom::FeaturePolicy* FeaturePolicy() const;
 
-  bool ModuleScriptsEnabled();
+  bool ModuleScriptsEnabled() const;
 
-  bool ImportMapsEnabled();
+  bool ImportMapsEnabled() const;
 
   /**
    * Find the (non-anonymous) content in this document for aFrame. It will

dom/html/HTMLScriptElement.cpp

@@ -150,33 +150,13 @@ void HTMLScriptElement::GetScriptCharset(nsAString& charset) {
   GetCharset(charset);
 }
 
-void HTMLScriptElement::FreezeExecutionAttrs(Document* aOwnerDoc) {
+void HTMLScriptElement::FreezeExecutionAttrs(const Document* aOwnerDoc) {
   if (mFrozen) {
     return;
   }
 
-  MOZ_ASSERT((mKind != ScriptKind::eModule) &&
-             (mKind != ScriptKind::eImportMap) && !mAsync && !mDefer &&
-             !mExternal);
-
   // Determine whether this is a(n) classic/module/importmap script.
-  nsAutoString type;
-  GetScriptType(type);
-  if (!type.IsEmpty()) {
-    if (aOwnerDoc->ModuleScriptsEnabled() &&
-        type.LowerCaseEqualsASCII("module")) {
-      mKind = ScriptKind::eModule;
-    }
-
-    // https://html.spec.whatwg.org/multipage/scripting.html#prepare-the-script-element
-    // Step 11. Otherwise, if the script block's type string is an ASCII
-    // case-insensitive match for the string "importmap", then set el's type to
-    // "importmap".
-    if (aOwnerDoc->ImportMapsEnabled() &&
-        type.LowerCaseEqualsASCII("importmap")) {
-      mKind = ScriptKind::eImportMap;
-    }
-  }
+  DetermineKindFromType(aOwnerDoc);
 
   // variation of this code in SVGScriptElement - check if changes
   // need to be transfered when modifying.  Note that we don't use GetSrc here

dom/html/HTMLScriptElement.h

@@ -32,7 +32,7 @@ class HTMLScriptElement final : public nsGenericHTMLElement,
   // nsIScriptElement
   virtual void GetScriptText(nsAString& text) const override;
   virtual void GetScriptCharset(nsAString& charset) override;
-  virtual void FreezeExecutionAttrs(Document* aOwnerDoc) override;
+  virtual void FreezeExecutionAttrs(const Document* aOwnerDoc) override;
   virtual CORSMode GetCORSMode() const override;
   virtual mozilla::dom::ReferrerPolicy GetReferrerPolicy() override;
 

dom/script/nsIScriptElement.cpp

@@ -7,10 +7,13 @@
 
 #include "nsIScriptElement.h"
 
+#include "mozilla/dom/Document.h"
 #include "mozilla/dom/ReferrerPolicyBinding.h"
 #include "nsIParser.h"
 #include "nsIWeakReference.h"
 
+using JS::loader::ScriptKind;
+
 void nsIScriptElement::SetCreatorParser(nsIParser* aParser) {
   mCreatorParser = do_GetWeakReference(aParser);
 }
@@ -51,3 +54,29 @@ already_AddRefed<nsIParser> nsIScriptElement::GetCreatorParser() {
 mozilla::dom::ReferrerPolicy nsIScriptElement::GetReferrerPolicy() {
   return mozilla::dom::ReferrerPolicy::_empty;
 }
+
+void nsIScriptElement::DetermineKindFromType(
+    const mozilla::dom::Document* aOwnerDoc) {
+  MOZ_ASSERT((mKind != ScriptKind::eModule) &&
+             (mKind != ScriptKind::eImportMap) && !mAsync && !mDefer &&
+             !mExternal);
+
+  nsAutoString type;
+  GetScriptType(type);
+
+  if (!type.IsEmpty()) {
+    if (aOwnerDoc->ModuleScriptsEnabled() &&
+        type.LowerCaseEqualsASCII("module")) {
+      mKind = ScriptKind::eModule;
+    }
+
+    // https://html.spec.whatwg.org/multipage/scripting.html#prepare-the-script-element
+    // Step 11. Otherwise, if the script block's type string is an ASCII
+    // case-insensitive match for the string "importmap", then set el's type to
+    // "importmap".
+    if (aOwnerDoc->ImportMapsEnabled() &&
+        type.LowerCaseEqualsASCII("importmap")) {
+      mKind = ScriptKind::eImportMap;
+    }
+  }
+}

dom/script/nsIScriptElement.h

@@ -106,34 +106,34 @@ class nsIScriptElement : public nsIScriptLoaderObserver {
    *  - GetScriptURI()
    *  - GetScriptExternal()
    */
-  virtual void FreezeExecutionAttrs(mozilla::dom::Document*) = 0;
+  virtual void FreezeExecutionAttrs(const mozilla::dom::Document*) = 0;
 
   /**
-   * Is the script a module script. Currently only supported by HTML scripts.
+   * Is the script a module script.
    */
   bool GetScriptIsModule() {
     MOZ_ASSERT(mFrozen, "Not ready for this call yet!");
     return mKind == JS::loader::ScriptKind::eModule;
   }
 
   /**
-   * Is the script an import map. Currently only supported by HTML scripts.
+   * Is the script an import map.
    */
   bool GetScriptIsImportMap() {
     MOZ_ASSERT(mFrozen, "Not ready for this call yet!");
     return mKind == JS::loader::ScriptKind::eImportMap;
   }
 
   /**
-   * Is the script deferred. Currently only supported by HTML scripts.
+   * Is the script deferred.
    */
   bool GetScriptDeferred() {
     MOZ_ASSERT(mFrozen, "Not ready for this call yet!");
     return mDefer;
   }
 
   /**
-   * Is the script async. Currently only supported by HTML scripts.
+   * Is the script async.
    */
   bool GetScriptAsync() {
     MOZ_ASSERT(mFrozen, "Not ready for this call yet!");
@@ -276,6 +276,11 @@ class nsIScriptElement : public nsIScriptLoaderObserver {
    */
   virtual nsIContent* GetAsContent() = 0;
 
+  /**
+   * Determine whether this is a(n) classic/module/importmap script.
+   */
+  void DetermineKindFromType(const mozilla::dom::Document* aOwnerDoc);
+
   /**
    * The start line number of the script.
    */

dom/svg/SVGScriptElement.cpp

@@ -14,6 +14,8 @@
 
 NS_IMPL_NS_NEW_SVG_ELEMENT_CHECK_PARSER(Script)
 
+using JS::loader::ScriptKind;
+
 namespace mozilla::dom {
 
 JSObject* SVGScriptElement::WrapNode(JSContext* aCx,
@@ -106,11 +108,14 @@ void SVGScriptElement::GetScriptCharset(nsAString& charset) {
   charset.Truncate();
 }
 
-void SVGScriptElement::FreezeExecutionAttrs(Document* aOwnerDoc) {
+void SVGScriptElement::FreezeExecutionAttrs(const Document* aOwnerDoc) {
   if (mFrozen) {
     return;
   }
 
+  // Determine whether this is a(n) classic/module/importmap script.
+  DetermineKindFromType(aOwnerDoc);
+
   if (mStringAttributes[HREF].IsExplicitlySet() ||
       mStringAttributes[XLINK_HREF].IsExplicitlySet()) {
     // variation of this code in nsHTMLScriptElement - check if changes
@@ -150,6 +155,12 @@ void SVGScriptElement::FreezeExecutionAttrs(Document* aOwnerDoc) {
     mExternal = true;
   }
 
+  bool async = (mExternal || mKind == ScriptKind::eModule) && Async();
+  bool defer = mExternal && Defer();
+
+  mDefer = !async && defer;
+  mAsync = async;
+
   mFrozen = true;
 }
 

dom/svg/SVGScriptElement.h

@@ -41,7 +41,7 @@ class SVGScriptElement final : public SVGScriptElementBase,
   // nsIScriptElement
   void GetScriptText(nsAString& text) const override;
   void GetScriptCharset(nsAString& charset) override;
-  void FreezeExecutionAttrs(Document* aOwnerDoc) override;
+  void FreezeExecutionAttrs(const Document* aOwnerDoc) override;
   CORSMode GetCORSMode() const override;
 
   // ScriptElement
@@ -59,6 +59,13 @@ class SVGScriptElement final : public SVGScriptElementBase,
   // WebIDL
   void GetType(nsAString& aType);
   void SetType(const nsAString& aType, ErrorResult& rv);
+  bool Async() { return mForceAsync || GetBoolAttr(nsGkAtoms::async); }
+  void SetAsync(bool aValue) {
+    mForceAsync = false;
+    SetBoolAttr(nsGkAtoms::async, aValue);
+  }
+  bool Defer() { return GetBoolAttr(nsGkAtoms::defer); }
+  void SetDefer(bool aDefer) { SetBoolAttr(nsGkAtoms::defer, aDefer); }
   void GetCrossOrigin(nsAString& aCrossOrigin);
   void SetCrossOrigin(const nsAString& aCrossOrigin, ErrorResult& aError);
   already_AddRefed<DOMSVGAnimatedString> Href();

dom/webidl/SVGScriptElement.webidl

@@ -14,8 +14,9 @@
 interface SVGScriptElement : SVGElement {
   [SetterThrows]
   attribute DOMString type;
-
-  // CORS attribute
+  // See https://github.com/w3c/svgwg/issues/918
+  attribute boolean async;
+  attribute boolean defer;
   [SetterThrows]
   attribute DOMString? crossOrigin;
 };

testing/web-platform/tests/svg/interact/scripted/defer.js

@@ -0,0 +1,4 @@
+t.step(() => {
+  assert_equals(script_run_status, "deferred", "script run status");
+});
+t.done();

testing/web-platform/tests/svg/interact/scripted/log.py

@@ -0,0 +1,13 @@
+import time
+
+def main(request, response):
+    response.headers.append(b"Content-Type", b"text/javascript")
+    try:
+        script_id = int(request.GET.first(b"id"))
+        delay = int(request.GET.first(b"sec"))
+    except:
+        response.set_error(400, u"Invalid parameter")
+
+    time.sleep(int(delay))
+
+    return u"log('%s')" % script_id