Add test for "constructor" lookups and correct job order in for-await loop

test/language/statements/for-await-of/ticks-with-async-iter-resolved-promise-and-constructor-lookup-two.js

@@ -0,0 +1,91 @@
+// Copyright (C) 2019 André Bargull. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-runtime-semantics-forin-div-ofbodyevaluation-lhs-stmt-iterator-lhskind-labelset
+description: >
+  Ensure the number of ticks and Promise constructor lookups is correct with custom async iterator.
+info: |
+  13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation ( lhs, stmt, iteratorRecord, iterationKind,
+                                                        lhsKind, labelSet [ , iteratorKind ] )
+  25.6.4.5.1 PromiseResolve
+  6.2.3.1 Await
+
+includes: [compareArray.js]
+flags: [async]
+features: [async-iteration]
+---*/
+
+// The expected event log.
+var expected = [
+  // Before entering loop.
+  "pre",
+
+  // Await
+  // -> PromiseResolve
+  "constructor",
+
+  // Await promise resolved.
+  "tick 1",
+
+  // In loop body.
+  "loop",
+
+  // Await
+  // -> PromiseResolve
+  "constructor",
+
+  // Await promise resolved
+  "tick 2",
+
+  // After exiting loop.
+  "post",
+];
+
+// The actual event log.
+var actual = [];
+
+// Custom async iterator returning the result of the synchronous iterator wrapped in a Promise.
+function toAsyncIterator(iterable) {
+  return {
+    [Symbol.asyncIterator]() {
+      var iter = iterable[Symbol.iterator]();
+      return {
+        next() {
+          return Promise.resolve(iter.next());
+        }
+      };
+    }
+  };
+}
+
+// Test function using for-await with a single, already resolved Promise.
+async function f() {
+  var p = Promise.resolve(0);
+  actual.push("pre");
+  for await (var x of toAsyncIterator([p])) {
+    actual.push("loop");
+  }
+  actual.push("post");
+}
+
+// Count the number of ticks needed to complete the loop and compare the actual log.
+Promise.resolve(0)
+  .then(() => actual.push("tick 1"))
+  .then(() => actual.push("tick 2"))
+  .then(() => {
+    assert.compareArray(actual, expected, "Ticks and constructor lookups");
+}).then($DONE, $DONE);
+
+// Redefine `Promise.constructor` in order to intercept "constructor" lookups from PromiseResolve.
+// (Perform last so that the lookups from SpeciesConstructor in `then` aren't logged.)
+Object.defineProperty(Promise.prototype, "constructor", {
+  get() {
+    actual.push("constructor");
+    return Promise;
+  },
+  configurable: true,
+});
+
+// Start the asynchronous function.
+f();

test/language/statements/for-await-of/ticks-with-async-iter-resolved-promise-and-constructor-lookup.js

@@ -0,0 +1,77 @@
+// Copyright (C) 2019 André Bargull. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-runtime-semantics-forin-div-ofbodyevaluation-lhs-stmt-iterator-lhskind-labelset
+description: >
+  Ensure the number of ticks and Promise constructor lookups is correct with custom async iterator.
+info: |
+  13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation ( lhs, stmt, iteratorRecord, iterationKind,
+                                                        lhsKind, labelSet [ , iteratorKind ] )
+  6.2.3.1 Await
+
+includes: [compareArray.js]
+flags: [async]
+features: [async-iteration]
+---*/
+
+// The expected event log.
+var expected = [
+  // Before entering loop.
+  "pre",
+
+  // Await promise resolved.
+  "tick 1",
+
+  // In loop body.
+  "loop",
+
+  // Await promise resolved
+  "tick 2",
+
+  // After exiting loop.
+  "post",
+];
+
+// The actual event log.
+var actual = [];
+
+// Custom async iterator directly using a synchronous iterator.
+function toAsyncIterator(iterable) {
+  return {
+    [Symbol.asyncIterator]() {
+      return iterable[Symbol.iterator]();
+    }
+  };
+}
+
+// Test function using for-await with a single, already resolved Promise.
+async function f() {
+  var p = Promise.resolve(0);
+  actual.push("pre");
+  for await (var x of toAsyncIterator([p])) {
+    actual.push("loop");
+  }
+  actual.push("post");
+}
+
+// Count the number of ticks needed to complete the loop and compare the actual log.
+Promise.resolve(0)
+  .then(() => actual.push("tick 1"))
+  .then(() => actual.push("tick 2"))
+  .then(() => {
+    assert.compareArray(actual, expected, "Ticks and constructor lookups");
+}).then($DONE, $DONE);
+
+// Redefine `Promise.constructor` in order to intercept "constructor" lookups from PromiseResolve.
+// (Perform last so that the lookups from SpeciesConstructor in `then` aren't logged.)
+Object.defineProperty(Promise.prototype, "constructor", {
+  get() {
+    actual.push("constructor");
+    return Promise;
+  },
+  configurable: true,
+});
+
+// Start the asynchronous function.
+f();

test/language/statements/for-await-of/ticks-with-sync-iter-resolved-promise-and-constructor-lookup.js

@@ -0,0 +1,92 @@
+// Copyright (C) 2019 André Bargull. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-runtime-semantics-forin-div-ofbodyevaluation-lhs-stmt-iterator-lhskind-labelset
+description: >
+  Ensure the number of ticks and Promise constructor lookups is correct with a Async-from-Sync iterator.
+info: |
+  13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation ( lhs, stmt, iteratorRecord, iterationKind,
+                                                        lhsKind, labelSet [ , iteratorKind ] )
+  25.1.4.2.1 %AsyncFromSyncIteratorPrototype%.next
+  25.1.4.4 AsyncFromSyncIteratorContinuation
+  25.6.4.5.1 PromiseResolve
+  6.2.3.1 Await
+
+includes: [compareArray.js]
+flags: [async]
+features: [async-iteration]
+---*/
+
+// The expected event log.
+var expected = [
+  // Before entering loop.
+  "pre",
+
+  // %AsyncFromSyncIteratorPrototype%.next
+  // -> AsyncFromSyncIteratorContinuation
+  //   -> PromiseResolve
+  "constructor",
+
+  // Await
+  // -> PromiseResolve
+  "constructor",
+
+  // Async-from-Sync Iterator promise resolved.
+  "tick 1",
+
+  // Await promise resolved.
+  "tick 2",
+
+  // In loop body.
+  "loop",
+
+  // Await
+  // -> PromiseResolve
+  "constructor",
+
+  // Async-from-Sync Iterator promise resolved.
+  "tick 3",
+
+  // Await promise resolved
+  "tick 4",
+
+  // After exiting loop.
+  "post",
+];
+
+// The actual event log.
+var actual = [];
+
+// Test function using for-await with a single, already resolved Promise.
+async function f() {
+  var p = Promise.resolve(0);
+  actual.push("pre");
+  for await (var x of [p]) {
+    actual.push("loop");
+  }
+  actual.push("post");
+}
+
+// Count the number of ticks needed to complete the loop and compare the actual log.
+Promise.resolve(0)
+  .then(() => actual.push("tick 1"))
+  .then(() => actual.push("tick 2"))
+  .then(() => actual.push("tick 3"))
+  .then(() => actual.push("tick 4"))
+  .then(() => {
+    assert.compareArray(actual, expected, "Ticks and constructor lookups");
+}).then($DONE, $DONE);
+
+// Redefine `Promise.constructor` in order to intercept "constructor" lookups from PromiseResolve.
+// (Perform last so that the lookups from SpeciesConstructor in `then` aren't logged.)
+Object.defineProperty(Promise.prototype, "constructor", {
+  get() {
+    actual.push("constructor");
+    return Promise;
+  },
+  configurable: true,
+});
+
+// Start the asynchronous function.
+f();