Bug 1722448 - Implement self.reportError(). r=emilio,smaug

This is mostly just copying and adjusting code from `AutoJSAPI::ReportException`.

Differential Revision: https://phabricator.services.mozilla.com/D121070

dom/base/nsGlobalWindowInner.cpp

@@ -4134,6 +4134,31 @@ void nsGlobalWindowInner::GetOrigin(nsAString& aOrigin) {
   nsContentUtils::GetUTFOrigin(GetPrincipal(), aOrigin);
 }
 
+// See also AutoJSAPI::ReportException
+void nsGlobalWindowInner::ReportError(JSContext* aCx,
+                                      JS::Handle<JS::Value> aError,
+                                      CallerType aCallerType,
+                                      ErrorResult& aRv) {
+  if (MOZ_UNLIKELY(!HasActiveDocument())) {
+    return aRv.Throw(NS_ERROR_XPC_SECURITY_MANAGER_VETO);
+  }
+
+  JS::ErrorReportBuilder jsReport(aCx);
+  JS::ExceptionStack exnStack(aCx, aError, nullptr);
+  if (!jsReport.init(aCx, exnStack, JS::ErrorReportBuilder::WithSideEffects)) {
+    return aRv.NoteJSContextException(aCx);
+  }
+
+  RefPtr<xpc::ErrorReport> xpcReport = new xpc::ErrorReport();
+  bool isChrome = aCallerType == CallerType::System;
+  xpcReport->Init(jsReport.report(), jsReport.toStringResult().c_str(),
+                  isChrome, WindowID());
+
+  JS::RootingContext* rcx = JS::RootingContext::get(aCx);
+  DispatchScriptErrorEvent(this, rcx, xpcReport, exnStack.exception(),
+                           exnStack.stack());
+}
+
 void nsGlobalWindowInner::Atob(const nsAString& aAsciiBase64String,
                                nsAString& aBinaryData, ErrorResult& aError) {
   aError = nsContentUtils::Atob(aAsciiBase64String, aBinaryData);

dom/base/nsGlobalWindowInner.h

@@ -714,6 +714,12 @@ class nsGlobalWindowInner final : public mozilla::dom::EventTarget,
   MOZ_CAN_RUN_SCRIPT
   void ClearInterval(int32_t aHandle);
   void GetOrigin(nsAString& aOrigin);
+
+  MOZ_CAN_RUN_SCRIPT
+  void ReportError(JSContext* aCx, JS::Handle<JS::Value> aError,
+                   mozilla::dom::CallerType aCallerType,
+                   mozilla::ErrorResult& aRv);
+
   void Atob(const nsAString& aAsciiBase64String, nsAString& aBinaryData,
             mozilla::ErrorResult& aError);
   void Btoa(const nsAString& aBinaryData, nsAString& aAsciiBase64String,

dom/webidl/WindowOrWorkerGlobalScope.webidl

@@ -16,6 +16,9 @@ interface mixin WindowOrWorkerGlobalScope {
   [Replaceable] readonly attribute USVString origin;
   readonly attribute boolean crossOriginIsolated;
 
+  [Throws, NeedsCallerType]
+  void reportError(any e);
+
   // base64 utility methods
   [Throws]
   DOMString btoa(DOMString btoa);

dom/workers/WorkerError.cpp

@@ -288,6 +288,7 @@ void WorkerErrorReport::ReportError(
       init.mMessage = aReport->mMessage;
       init.mFilename = aReport->mFilename;
       init.mLineno = aReport->mLineNumber;
+      init.mColno = aReport->mColumnNumber;
       init.mError = aException;
     }
 

dom/workers/WorkerScope.cpp

@@ -279,6 +279,26 @@ nsISerialEventTarget* WorkerGlobalScopeBase::EventTargetFor(
   return mSerialEventTarget;
 }
 
+// See also AutoJSAPI::ReportException
+void WorkerGlobalScopeBase::ReportError(JSContext* aCx,
+                                        JS::Handle<JS::Value> aError,
+                                        CallerType, ErrorResult& aRv) {
+  JS::ErrorReportBuilder jsReport(aCx);
+  JS::ExceptionStack exnStack(aCx, aError, nullptr);
+  if (!jsReport.init(aCx, exnStack, JS::ErrorReportBuilder::WithSideEffects)) {
+    return aRv.NoteJSContextException(aCx);
+  }
+
+  // Before invoking ReportError, put the exception back on the context,
+  // because it may want to put it in its error events and has no other way
+  // to get hold of it.  After we invoke ReportError, clear the exception on
+  // cx(), just in case ReportError didn't.
+  JS::SetPendingExceptionStack(aCx, exnStack);
+  mWorkerPrivate->ReportError(aCx, jsReport.toStringResult(),
+                              jsReport.report());
+  JS_ClearPendingException(aCx);
+}
+
 void WorkerGlobalScopeBase::Atob(const nsAString& aAtob, nsAString& aOut,
                                  ErrorResult& aRv) const {
   mWorkerPrivate->AssertIsOnWorkerThread();

dom/workers/WorkerScope.h

@@ -121,6 +121,10 @@ class WorkerGlobalScopeBase : public DOMEventTargetHelper,
     MOZ_CRASH("AbstractMainThreadFor not supported for workers.");
   }
 
+  MOZ_CAN_RUN_SCRIPT
+  void ReportError(JSContext* aCx, JS::Handle<JS::Value> aError,
+                   CallerType aCallerType, ErrorResult& aRv);
+
   // atob, btoa, and dump are declared (separately) by both WorkerGlobalScope
   // and WorkerDebuggerGlobalScope WebIDL interfaces
   void Atob(const nsAString& aAtob, nsAString& aOut, ErrorResult& aRv) const;