Add AsyncFromSyncIterator tests

test/built-ins/AsyncFromSyncIteratorPrototype/return/return-null.js

@@ -0,0 +1,53 @@
+// Copyright (C) 2020 Alexey Shvayka. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-%asyncfromsynciteratorprototype%.return
+description: >
+  If syncIterator's "return" method is `null`,
+  a Promise resolved with `undefined` value is returned.
+info: |
+  %AsyncFromSyncIteratorPrototype%.return ( value )
+
+  [...]
+  5. Let return be GetMethod(syncIterator, "return").
+  [...]
+  7. If return is undefined, then
+    a. Let iterResult be ! CreateIterResultObject(value, true).
+    b. Perform ! Call(promiseCapability.[[Resolve]], undefined, « iterResult »).
+    c. Return promiseCapability.[[Promise]].
+
+  GetMethod ( V, P )
+
+  [...]
+  2. Let func be ? GetV(V, P).
+  3. If func is either undefined or null, return undefined.
+flags: [async]
+features: [async-iteration]
+---*/
+
+var iterationCount = 0;
+var returnGets = 0;
+
+var syncIterator = {
+  [Symbol.iterator]() {
+    return this;
+  },
+  next() {
+    return {value: 1, done: false};
+  },
+  get return() {
+    returnGets += 1;
+    return null;
+  },
+};
+
+(async function() {
+  for await (let _ of syncIterator) {
+    iterationCount += 1;
+    break;
+  }
+
+  assert.sameValue(iterationCount, 1);
+  assert.sameValue(returnGets, 1);
+}()).then($DONE, $DONE);

test/built-ins/AsyncFromSyncIteratorPrototype/throw/throw-null.js

@@ -0,0 +1,62 @@
+// Copyright (C) 2020 Alexey Shvayka. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-%asyncfromsynciteratorprototype%.throw
+description: >
+  If syncIterator's "throw" method is `null`,
+  a Promise rejected with provided value is returned.
+info: |
+  %AsyncFromSyncIteratorPrototype%.throw ( value )
+
+  [...]
+  5. Let throw be GetMethod(syncIterator, "throw").
+  [...]
+  7. If throw is undefined, then
+    a. Perform ! Call(promiseCapability.[[Reject]], undefined, « value »).
+    b. Return promiseCapability.[[Promise]].
+
+  GetMethod ( V, P )
+
+  [...]
+  2. Let func be ? GetV(V, P).
+  3. If func is either undefined or null, return undefined.
+flags: [async]
+features: [async-iteration]
+---*/
+
+var throwGets = 0;
+var syncIterator = {
+  [Symbol.iterator]() {
+    return this;
+  },
+  next() {
+    return {value: 1, done: false};
+  },
+  get throw() {
+    throwGets += 1;
+    return null;
+  },
+};
+
+async function* asyncGenerator() {
+  yield* syncIterator;
+}
+
+var asyncIterator = asyncGenerator();
+asyncIterator.next().then(function() {
+  var thrownError = { name: "err" };
+  asyncIterator.throw(thrownError).then(
+    function(result) {
+      throw new Test262Error("Promise should be rejected, got: " + result.value);
+    },
+    function(err) {
+      assert.sameValue(err, thrownError);
+
+      asyncIterator.next().then(function(result) {
+        assert.sameValue(result.value, undefined);
+        assert.sameValue(result.done, true);
+      }).then($DONE, $DONE);
+    }
+  ).catch($DONE);
+}).catch($DONE);