[promises] Port ResolvePromise to TF

src/js/promise.js

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 (function(global, utils, extrasUtils) {
 
 "use strict";
 
 %CheckIsBootstrapping();
 
@@ skipping 100 matching lines @@
 // For bootstrapper.
 
 // This is used by utils and v8-extras.
 function PromiseCreate() {
   return %promise_internal_constructor();
 }
 
 // ES#sec-promise-resolve-functions
 // Promise Resolve Functions, steps 6-13
 function ResolvePromise(promise, resolution) {
-  if (resolution === promise) {
-    var exception = %make_type_error(kPromiseCyclic, resolution);
-    %PromiseReject(promise, exception, true);
-    return;
-  }
-  if (IS_RECEIVER(resolution)) {
-    // 25.4.1.3.2 steps 8-12
-    try {
-      var then = resolution.then;
-    } catch (e) {
-      %PromiseReject(promise, e, true);
-      return;
-    }
-
-    // Resolution is a native promise and if it's already resolved or
-    // rejected, shortcircuit the resolution procedure by directly
-    // reusing the value from the promise.
-    if (%is_promise(resolution) && then === PromiseThen) {
-      var thenableState = %PromiseStatus(resolution);
-      if (thenableState === kFulfilled) {
-        // This goes inside the if-else to save one symbol lookup in
-        // the slow path.
-        var thenableValue = %PromiseResult(resolution);
-        %PromiseFulfill(promise, kFulfilled, thenableValue);
-        SET_PRIVATE(promise, promiseHasHandlerSymbol, true);
-        return;
-      } else if (thenableState === kRejected) {
-        var thenableValue = %PromiseResult(resolution);
-        if (!HAS_DEFINED_PRIVATE(resolution, promiseHasHandlerSymbol)) {
-          // Promise has already been rejected, but had no handler.
-          // Revoke previously triggered reject event.
-          %PromiseRevokeReject(resolution);
-        }
-        // Don't cause a debug event as this case is forwarding a rejection
-        %PromiseReject(promise, thenableValue, false);
-        SET_PRIVATE(resolution, promiseHasHandlerSymbol, true);
-        return;
-      }
-    }
-
-    if (IS_CALLABLE(then)) {
-      if (DEBUG_IS_ACTIVE && %is_promise(resolution)) {
-          // Mark the dependency of the new promise on the resolution
-        SET_PRIVATE(resolution, promiseHandledBySymbol, promise);
-      }
-      %EnqueuePromiseResolveThenableJob(promise, resolution, then);
-      return;
-    }
-  }
-  %PromiseFulfill(promise, kFulfilled, resolution);
+    %resolve_promise(promise, resolution);

[jgruber, 2016/12/05 09:25:17]

Can we replace calls to ResolvePromise by %resolve_promise and remove
ResolvePromise?

[gsathya, 2016/12/05 16:03:05]

Nope. We use this in async-await and v8-extras

[caitp, 2016/12/05 16:22:51]

Couldn't we just export %resolve_promise from the bootstrapper and avoid
creating the extra closure in promise.js?

 }
 
 // Only used by async-await.js
 function RejectPromise(promise, reason, debugEvent) {
   %PromiseReject(promise, reason, debugEvent);
 }
 
 // Export to bindings
 function DoRejectPromise(promise, reason) {
   %PromiseReject(promise, reason, true);
@@ skipping 263 matching lines @@
 
 utils.InstallFunctions(GlobalPromise, DONT_ENUM, [
   "reject", PromiseReject,
   "all", PromiseAll,
   "race", PromiseRace,
   "resolve", PromiseResolve
 ]);
 
 utils.InstallGetter(GlobalPromise, speciesSymbol, PromiseSpecies);
 
-utils.InstallFunctions(GlobalPromise.prototype, DONT_ENUM, [
-  "catch", PromiseCatch
-]);
+%SetCode(GlobalPromise.prototype.catch, PromiseCatch);

[jgruber, 2016/12/05 09:25:17]

This and below + corresponding changes in bootstrapper seem unrelated?

[gsathya, 2016/12/05 16:03:05]

I need to install an empty .catch in bootstrapper and set the code here,
otherwise the prototype will change here and my map checks will always fail.

[jgruber, 2016/12/07 12:59:38]

Acknowledged.

 
 %InstallToContext([
   "promise_catch", PromiseCatch,
   "promise_create", PromiseCreate,
   "promise_has_user_defined_reject_handler", PromiseHasUserDefinedRejectHandler,
   "promise_reject", DoRejectPromise,
   // TODO(gsathya): Remove this once we update the promise builtin.
   "promise_internal_reject", RejectPromise,
   "promise_resolve", ResolvePromise,
-  "promise_then", PromiseThen,
   "promise_handle", PromiseHandle,
   "promise_debug_get_info", PromiseDebugGetInfo,
   "new_promise_capability", NewPromiseCapability,
   "internal_promise_capability", CreateInternalPromiseCapability,
   "promise_id_resolve_handler", PromiseIdResolveHandler,
   "promise_id_reject_handler", PromiseIdRejectHandler
 ]);
 
 // This allows extras to create promises quickly without building extra
 // resolve/reject closures, and allows them to later resolve and reject any
 // promise without having to hold on to those closures forever.
 utils.InstallFunctions(extrasUtils, 0, [
   "createPromise", PromiseCreate,
   "resolvePromise", ResolvePromise,
   "rejectPromise", DoRejectPromise,
   "markPromiseAsHandled", MarkPromiseAsHandled
 ]);
 
 utils.Export(function(to) {
   to.PromiseCreate = PromiseCreate;
   to.PromiseThen = PromiseThen;
 
   to.CreateInternalPromiseCapability = CreateInternalPromiseCapability;
   to.ResolvePromise = ResolvePromise;
   to.RejectPromise = RejectPromise;
 });
 
 })