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1// Copyright 2019 the V8 project authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include 'src/builtins/builtins-constructor-gen.h'
6#include 'src/builtins/builtins-promise-gen.h'
7
8namespace runtime {
9extern transitioning runtime
10DebugPushPromise(implicit context: Context)(JSAny): JSAny;
11
12extern transitioning runtime
13DebugPopPromise(implicit context: Context)(): JSAny;
14
15extern transitioning runtime
16PromiseHookInit(implicit context: Context)(Object, Object): JSAny;
17}
18
19// https://tc39.es/ecma262/#sec-promise-constructor
20namespace promise {
21
22extern runtime IncrementUseCounter(Context, Smi): void;
23type UseCounterFeature extends int31
24constexpr 'v8::Isolate::UseCounterFeature';
25const kPromiseConstructorReturnedUndefined: constexpr UseCounterFeature
26    generates 'v8::Isolate::kPromiseConstructorReturnedUndefined';
27
28extern macro
29IsDebugActive(): bool;
30
31transitioning macro
32HasAccessCheckFailed(implicit context: Context)(
33    nativeContext: NativeContext, promiseFun: JSAny, executor: JSAny): bool {
34  BranchIfAccessCheckFailed(nativeContext, promiseFun, executor)
35      otherwise return true;
36  return false;
37}
38
39extern macro ConstructorBuiltinsAssembler::FastNewObject(
40    Context, JSFunction, JSReceiver): JSObject;
41
42extern macro
43PromiseBuiltinsAssembler::IsPromiseHookEnabledOrHasAsyncEventDelegate(): bool;
44
45// https://tc39.es/ecma262/#sec-promise-executor
46transitioning javascript builtin
47PromiseConstructor(
48    js-implicit context: NativeContext, receiver: JSAny,
49    newTarget: JSAny)(executor: JSAny): JSAny {
50  // 1. If NewTarget is undefined, throw a TypeError exception.
51  if (newTarget == Undefined) {
52    ThrowTypeError(MessageTemplate::kNotAPromise, newTarget);
53  }
54
55  // 2. If IsCallable(executor) is false, throw a TypeError exception.
56  if (!Is<Callable>(executor)) {
57    ThrowTypeError(MessageTemplate::kResolverNotAFunction, executor);
58  }
59
60  const promiseFun = *NativeContextSlot(ContextSlot::PROMISE_FUNCTION_INDEX);
61
62  // Silently fail if the stack looks fishy.
63  if (HasAccessCheckFailed(context, promiseFun, executor)) {
64    IncrementUseCounter(
65        context, SmiConstant(kPromiseConstructorReturnedUndefined));
66    return Undefined;
67  }
68
69  let result: JSPromise;
70  if (promiseFun == newTarget) {
71    result = NewJSPromise();
72  } else {
73    result = UnsafeCast<JSPromise>(
74        FastNewObject(context, promiseFun, UnsafeCast<JSReceiver>(newTarget)));
75    PromiseInit(result);
76    if (IsPromiseHookEnabledOrHasAsyncEventDelegate()) {
77      runtime::PromiseHookInit(result, Undefined);
78    }
79  }
80
81  const isDebugActive = IsDebugActive();
82  if (isDebugActive) runtime::DebugPushPromise(result);
83
84  const funcs = CreatePromiseResolvingFunctions(result, True, context);
85  const resolve = funcs.resolve;
86  const reject = funcs.reject;
87  try {
88    Call(context, UnsafeCast<Callable>(executor), Undefined, resolve, reject);
89  } catch (e) {
90    Call(context, reject, Undefined, e);
91  }
92
93  if (isDebugActive) runtime::DebugPopPromise();
94  return result;
95}
96
97// Promise.prototype.catch ( onRejected )
98// https://tc39.es/ecma262/#sec-promise.prototype.catch
99transitioning javascript builtin
100PromisePrototypeCatch(
101    js-implicit context: Context, receiver: JSAny)(onRejected: JSAny): JSAny {
102  // 1. Let promise be the this value.
103  // 2. Return ? Invoke(promise, "then", « undefined, onRejected »).
104  const nativeContext = LoadNativeContext(context);
105  return UnsafeCast<JSAny>(
106      InvokeThen(nativeContext, receiver, Undefined, onRejected));
107}
108}
109