Commit 7d406320 authored by Karl Tomlinson's avatar Karl Tomlinson
Browse files

Bug 1473463 evaluate worklet scripts as modules without support for nested import r=baku 

The separation of parse and evaluate steps permits implementation of behavior
on unhandled exception during evaluation that is different from that on
parsing error.

Implementation of fetching a complete module script graph is tracked in
https://bugzilla.mozilla.org/show_bug.cgi?id=1572644

Differential Revision: https://phabricator.services.mozilla.com/D41339

--HG--
extra : moz-landing-system : lando
parent 859de114

dom/worklet/Worklet.cpp

+40 −12
Original line number Diff line number Diff line
@@ -16,7 +16,7 @@ 
#include "mozilla/dom/ScriptSettings.h"

#include "mozilla/dom/ScriptLoader.h"

#include "mozilla/dom/WorkletImpl.h"

#include "js/CompilationAndEvaluation.h"

#include "js/Modules.h"

#include "js/SourceText.h"

#include "nsIInputStreamPump.h"

#include "nsIThreadRetargetableRequest.h"
@@ -50,6 +50,8 @@ class ExecutionRunnable final : public Runnable { 


  void RunOnMainThread();



  bool ParseAndLinkModule(JSContext* aCx, JS::MutableHandle<JSObject*> aModule);



  RefPtr<WorkletFetchHandler> mHandler;

  RefPtr<WorkletImpl> mWorkletImpl;

  JS::UniqueTwoByteChars mScriptBuffer;
@@ -336,6 +338,33 @@ ExecutionRunnable::Run() { 
  return NS_OK;

}



bool ExecutionRunnable::ParseAndLinkModule(

    JSContext* aCx, JS::MutableHandle<JSObject*> aModule) {

  JS::CompileOptions compileOptions(aCx);

  compileOptions.setIntroductionType("Worklet");

  compileOptions.setFileAndLine(mHandler->URL().get(), 0);

  compileOptions.setIsRunOnce(true);

  compileOptions.setNoScriptRval(true);



  JS::SourceText<char16_t> buffer;

  if (!buffer.init(aCx, std::move(mScriptBuffer), mScriptLength)) {

    return false;

  }

  JS::Rooted<JSObject*> module(aCx,

                               JS::CompileModule(aCx, compileOptions, buffer));

  if (!module) {

    return false;

  }

  // Link() was previously named Instantiate().

  // https://github.com/tc39/ecma262/pull/1312

  // Any imports will fail here - bug 1572644.

  if (!JS::ModuleInstantiate(aCx, module)) {

    return false;

  }

  aModule.set(module);

  return true;

}



void ExecutionRunnable::RunOnWorkletThread() {

  WorkletThread::EnsureCycleCollectedJSContext(mParentRuntime);
@@ -346,19 +375,10 @@ void ExecutionRunnable::RunOnWorkletThread() { 
  JSContext* cx = aes.cx();



  JS::Rooted<JSObject*> globalObj(cx, globalScope->GetGlobalJSObject());



  JS::CompileOptions compileOptions(cx);

  compileOptions.setIntroductionType("Worklet");

  compileOptions.setFileAndLine(mHandler->URL().get(), 0);

  compileOptions.setIsRunOnce(true);

  compileOptions.setNoScriptRval(true);



  JSAutoRealm ar(cx, globalObj);



  JS::Rooted<JS::Value> unused(cx);

  JS::SourceText<char16_t> buffer;

  if (!buffer.init(cx, std::move(mScriptBuffer), mScriptLength) ||

      !JS::Evaluate(cx, compileOptions, buffer, &unused)) {

  JS::Rooted<JSObject*> module(cx);

  if (!ParseAndLinkModule(cx, &module)) {

    ErrorResult error;

    error.MightThrowJSException();

    error.StealExceptionFromJSContext(cx);
@@ -366,6 +386,14 @@ void ExecutionRunnable::RunOnWorkletThread() { 
    return;

  }



  // https://drafts.css-houdini.org/worklets/#fetch-and-invoke-a-worklet-script

  // invokes

  // https://html.spec.whatwg.org/multipage/webappapis.html#run-a-module-script

  // without /rethrow errors/ and so unhandled exceptions do not cause the

  // promise to be rejected.

  JS::ModuleEvaluate(cx, module);

  JS::Rooted<JS::Value> unused(cx);



  // All done.

  mResult = NS_OK;

}

dom/worklet/tests/test_exception.html

+2 −2
Original line number Diff line number Diff line
@@ -32,9 +32,9 @@ function runTestInIframe() { 
    return audioContext.audioWorklet.addModule("worklet_exception.js")

  })

  .then(() => {

    ok(false, "We should not be called!");

    ok(true, "The script threw but we are still here.");

  }, () => {

    ok(true, "The script thrown but we are still here.");

    ok(false, "We should not be called!");

  })



  .then(() => {

testing/web-platform/meta/webaudio/the-audio-api/the-audioworklet-interface/audioworkletglobalscope-sample-rate.https.html.ini

+6 −1
Original line number Diff line number Diff line 
[audioworkletglobalscope-sample-rate.https.html]

  bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1572627

  expected:

    if release_or_beta: OK

    ERROR

  [\n      Test sampleRate in AudioWorkletGlobalScope\n    ]

    expected: FAIL

    expected:

      if release_or_beta: FAIL

testing/web-platform/meta/worklets/audio-worklet-import.https.html.ini

+2 −1
Original line number Diff line number Diff line
@@ -18,7 +18,8 @@ 
    expected: FAIL



  [Importing a script which throws should still resolve the given promise.]

    expected: FAIL

    expected:

      if release_or_beta: FAIL



  [Importing a non-existent script rejects the given promise with an AbortError.]

    expected: FAIL