Explicit resource management iterator return

test/built-ins/AsyncIteratorPrototype/Symbol.asyncDispose/invokes-return.js

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+// Copyright (C) 2023 Ron Buckton. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-%asynciteratorprototype%-@@asyncDispose
+description: Return value of @@asyncDispose on %AsyncIteratorPrototype%
+info: |
+  %AsyncIteratorPrototype% [ @@asyncDispose ] ( )
+
+  1. Let O be the this value.
+  2. Let promiseCapability be ! NewPromiseCapability(%Promise%).
+  3. Let return be GetMethod(O, "return").
+  4. IfAbruptRejectPromise(return, promiseCapability).
+  5. If return is undefined, then
+    a. Perform ! Call(promiseCapability.[[Resolve]], undefined, « undefined »).
+  6. Else,
+    a. Let result be Call(return, O, « undefined »).
+    b. IfAbruptRejectPromise(result, promiseCapability).
+    c. Let resultWrapper be Completion(PromiseResolve(%Promise%, result)).
+    d. IfAbruptRejectPromise(resultWrapper, promiseCapability).
+    e. Let unwrap be a new Abstract Closure that performs the following steps when called:
+      i. Return undefined.
+    f. Let onFulfilled be CreateBuiltinFunction(unwrap, 1, "", « »).
+    g. Perform PerformPromiseThen(resultWrapper, onFulfilled, undefined, promiseCapability).
+  7. Return promiseCapability.[[Promise]].
+
+flags: [async]
+includes: [asyncHelpers.js]
+features: [explicit-resource-management]
+---*/
+
+asyncTest(async function () {
+  async function* generator() {}
+  const AsyncIteratorPrototype = Object.getPrototypeOf(Object.getPrototypeOf(generator.prototype))
+
+  const iter = Object.create(AsyncIteratorPrototype);
+  var returnCalled = false;
+  iter.return = async function () {
+    returnCalled = true;
+    return { done: true };
+  };
+
+  await iter[Symbol.asyncDispose]();
+  assert.sameValue(returnCalled, true);
+});

test/built-ins/AsyncIteratorPrototype/Symbol.asyncDispose/return-val.js

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+// Copyright (C) 2023 Ron Buckton. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-%asynciteratorprototype%-@@asyncDispose
+description: Return value of @@asyncDispose on %AsyncIteratorPrototype%
+info: |
+  %AsyncIteratorPrototype% [ @@asyncDispose ] ( )
+
+  1. Let O be the this value.
+  2. Let promiseCapability be ! NewPromiseCapability(%Promise%).
+  3. Let return be GetMethod(O, "return").
+  4. IfAbruptRejectPromise(return, promiseCapability).
+  5. If return is undefined, then
+    a. Perform ! Call(promiseCapability.[[Resolve]], undefined, « undefined »).
+  6. Else,
+    a. Let result be Call(return, O, « undefined »).
+    b. IfAbruptRejectPromise(result, promiseCapability).
+    c. Let resultWrapper be Completion(PromiseResolve(%Promise%, result)).
+    d. IfAbruptRejectPromise(resultWrapper, promiseCapability).
+    e. Let unwrap be a new Abstract Closure that performs the following steps when called:
+      i. Return undefined.
+    f. Let onFulfilled be CreateBuiltinFunction(unwrap, 1, "", « »).
+    g. Perform PerformPromiseThen(resultWrapper, onFulfilled, undefined, promiseCapability).
+  7. Return promiseCapability.[[Promise]].
+
+features: [explicit-resource-management]
+---*/
+
+async function* generator() {}
+const AsyncIteratorPrototype = Object.getPrototypeOf(Object.getPrototypeOf(generator.prototype))
+
+assert(AsyncIteratorPrototype[Symbol.asyncDispose]() instanceof Promise);

test/built-ins/Iterator/prototype/Symbol.dispose/invokes-return.js

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+// Copyright (C) 2023 Ron Buckton. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-%iteratorprototype%-@@dispose
+description: Return value of @@dispose on %IteratorPrototype%
+info: |
+  %IteratorPrototype% [ @@dispose ] ( )
+
+  1. Let O be the this value.
+  2. Let return be ? GetMethod(O, "return").
+  3. If return is not undefined, then
+    a. Perform ? Call(return, O, « »).
+  4. Return undefined.
+
+features: [explicit-resource-management]
+---*/
+
+const IteratorPrototype = Object.getPrototypeOf(
+  Object.getPrototypeOf([][Symbol.iterator]())
+);
+
+const iter = Object.create(IteratorPrototype);
+var returnCalled = false;
+iter.return = function () {
+  returnCalled = true;
+  return { done: true };
+};
+
+iter[Symbol.dispose]();
+assert.sameValue(returnCalled, true);

test/built-ins/Iterator/prototype/Symbol.dispose/return-val.js

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+// Copyright (C) 2023 Ron Buckton. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-%iteratorprototype%-@@dispose
+description: Return value of @@dispose on %IteratorPrototype%
+info: |
+  %IteratorPrototype% [ @@dispose ] ( )
+
+  1. Let O be the this value.
+  2. Let return be ? GetMethod(O, "return").
+  3. If return is not undefined, then
+    a. Perform ? Call(return, O, « »).
+  4. Return undefined.
+
+features: [explicit-resource-management]
+---*/
+const IteratorPrototype = Object.getPrototypeOf(
+  Object.getPrototypeOf([][Symbol.iterator]())
+);
+
+assert.sameValue(IteratorPrototype[Symbol.dispose](), undefined);