Mark await expressions as caught or uncaught

test/mjsunit/harmony/async-debug-caught-exception2.js

+// Copyright 2016 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.
+
+// Flags: --allow-natives-syntax --harmony-async-await --expose-debug-as debug
+
+Debug = debug.Debug
+
+let exception = null;

[jgruber, 2016/09/08 10:19:58]

This is never set.

[Dan Ehrenberg, 2016/09/08 22:34:04]

Deleted

+let events = 0;
+
+function listener(event, exec_state, event_data, data) {
+  if (event != Debug.DebugEvent.Exception) return;
+  try {
+    events++;

[jgruber, 2016/09/08 10:19:58]

Can this ever fail?

[Dan Ehrenberg, 2016/09/08 22:34:04]

Deleted

+  } catch (e) {
+    %AbortJS(e + "\n" + e.stack);
+  }
+}
+
+async function thrower() {
+  throw "a";  // Exception a
+}
+
+var reject = () => Promise.reject("b");  // Exception b
+
+async function awaitReturn() { await 1; return; }
+
+async function scalar() { return 1; }
+
+function nothing() { return 1; }
+
+function rejectConstructor() {
+  return new Promise((resolve, reject) => reject("c"));  // Exception c
+}
+
+async function argThrower(x = (() => { throw "d"; })()) { }  // Exception d
+
+async function awaitThrow() {
+  await undefined;
+  throw "e";  // Exception e
+}
+
+function constructorThrow() {
+  return new Promise((resolve, reject) =>
+    Promise.resolve().then(() =>
+      reject("f")  // Exception f
+    )
+  );
+}
+
+function suppressThrow() {
+  return thrower();
+}
+
+async function caught(producer) {
+  try {
+    await producer();
+  } catch (e) {
+  }
+}
+
+async function uncaught(producer) {
+  await producer();
+}
+
+async function caught(producer) {

[jgruber, 2016/09/08 10:19:58]

Duplicate from above.

[Dan Ehrenberg, 2016/09/08 22:34:04]

Deleted

+  try {
+    await producer();
+  } catch (e) {
+  }
+}
+
+async function indirectUncaught(producer) {
+  await uncaught(producer);
+}
+
+async function indirectCaught(producer) {
+  try {
+    await uncaught(producer);
+  } catch (e) {
+  }
+}
+
+function dotCatch(producer) {
+  Promise.resolve(producer()).catch(() => {});
+}
+
+function indirectReturnDotCatch(producer) {
+  (async() => producer())().catch(() => {});
+}
+
+function indirectAwaitDotCatch(producer) {
+  (async() => await producer())().catch(() => {});
+}
+
+function nestedDotCatch(producer) {
+  Promise.resolve(producer()).then().catch(() => {});
+}
+
+async function indirectAwaitCatch(producer) {
+  try {
+    await (() => producer())();
+  } catch (e) {
+  }
+}
+
+let catches = [caught, indirectCaught, indirectAwaitCatch];
+let noncatches = [uncaught, indirectUncaught];
+let lateCatches = [dotCatch, indirectReturnDotCatch, indirectAwaitDotCatch, nestedDotCatch];

[jgruber, 2016/09/08 10:19:58]

Nit: 80 columns here and below.

[Dan Ehrenberg, 2016/09/08 22:34:04]

Fixed

+
+let throws = [thrower, reject, argThrower, suppressThrow];
+let nonthrows = [awaitReturn, scalar, nothing];
+// TODO(littledan): Build a dependency graph to track the relationship between Promises
+// linked by async/await, and enable tests so that
+// let lateThrows = [awaitThrow, constructorThrow, rejectConstructor];

[jgruber, 2016/09/08 10:19:58]

Maybe we could add these (awaitThrow, constructorThrow, rejectConstructor,
lateThrows, the for loop below and the comment) once they become relevant?
Otherwise it's just dead code here. But I guess I'm fine with either way.

[Dan Ehrenberg, 2016/09/08 22:34:04]

Done

[Dan Ehrenberg, 2016/09/08 22:34:04]

Done

+let lateThrows = [];
+
+let cases = [];
+
+for (let producer of throws.concat(lateThrows)) {
+  for (let consumer of catches) {
+    cases.push({ producer, consumer, expectedEvents: 1, caught: true });
+    cases.push({ producer, consumer, expectedEvents: 0, caught: false });
+  }
+}
+
+for (let producer of throws.concat(lateThrows)) {
+  for (let consumer of noncatches) {
+    cases.push({ producer, consumer, expectedEvents: 1, caught: true });
+    cases.push({ producer, consumer, expectedEvents: 1, caught: false });
+  }
+}
+
+for (let producer of nonthrows) {
+  for (let consumer of catches.concat(noncatches, lateCatches)) {
+    cases.push({ producer, consumer, expectedEvents: 0, caught: true });
+    cases.push({ producer, consumer, expectedEvents: 0, caught: false });
+  }
+}
+
+for (let producer of lateThrows) {
+  for (let consumer of lateCatches) {
+    cases.push({ producer, consumer, expectedEvents: 1, caught: true });
+    cases.push({ producer, consumer, expectedEvents: 0, caught: false });
+  }
+}
+
+for (let producer of throws) {
+  for (let consumer of lateCatches) {
+    cases.push({ producer, consumer, expectedEvents: 1, caught: true });
+    cases.push({ producer, consumer, expectedEvents: 1, caught: false });
+  }
+}
+
+const tonsOfTasks = 50;
+
+function afterWaiting(callback, tasks = tonsOfTasks) {

[jgruber, 2016/09/08 10:19:58]

This appears to be unused.

[Dan Ehrenberg, 2016/09/08 22:34:05]

Removed

+  if (tasks === 0) callback();
+  else %EnqueueMicrotask(() => afterWaiting(callback, tasks - 1));
+}
+
+let failureCount = 0;
+
+for (let {producer, consumer, expectedEvents, caught} of cases) {
+  events = 0;
+  Debug.setListener(listener);
+  if (caught)
+    Debug.setBreakOnException();
+  else
+    Debug.setBreakOnUncaughtException();
+
+  consumer(producer);
+
+  %RunMicrotasks();
+
+  Debug.setListener(null);
+  if (caught) Debug.clearBreakOnException();
+  else Debug.clearBreakOnUncaughtException();
+  if (expectedEvents != events || exception) {
+    print(`producer ${producer} consumer ${consumer} expectedEvents ` +
+          `${expectedEvents} caught ${caught} events ${events} exception ` +
+          `${exception}`);
+    failureCount++;
+  }
+}
+
+if (failureCount > 0) {

[jgruber, 2016/09/08 10:19:58]

What about assertEquals() here (or above in the loop)?

[Dan Ehrenberg, 2016/09/08 22:34:04]

Now it exits at the first failure (though this form was useful for development)

+  print(`failureCount ${failureCount}`);
+  quit(1);
+}