[inspector] async stacks for Promise.then calls...

test/inspector/debugger/async-promise-late-then.js

Index: test/inspector/debugger/async-promise-late-then.js
diff --git a/test/inspector/debugger/async-promise-late-then.js b/test/inspector/debugger/async-promise-late-then.js
new file mode 100644
index 0000000000000000000000000000000000000000..c0b588a9ccd2e39273143372edbb32c3c333e33a
--- /dev/null
+++ b/test/inspector/debugger/async-promise-late-then.js
@@ -0,0 +1,48 @@
+// 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: --expose-gc
+
+print('Checks async stack for late .then handlers with gc');
+
+InspectorTest.addScript(`
+function foo1() {
+  gc();
+  debugger;
+}
+
+function test() {
+  var resolve1;
+  var p1 = new Promise(resolve => resolve1 = resolve);
+  gc();
+  var p2 = p1.then(foo1);
+  gc();
+  resolve1();
+  gc();
+  var p3 = p1.then(foo1);
+  gc();
+  var p4 = p1.then(foo1);
+  gc();
+  return Promise.all([p2,p3,p4]);
+}
+//# sourceURL=test.js`, 8, 26);
+
+InspectorTest.setupScriptMap();
+Protocol.Debugger.onPaused(message => {
+  InspectorTest.logCallFrames(message.params.callFrames);
+  var asyncStackTrace = message.params.asyncStackTrace;
+  while (asyncStackTrace) {
+    InspectorTest.log(`-- ${asyncStackTrace.description} --`);
+    InspectorTest.logCallFrames(asyncStackTrace.callFrames);
+    asyncStackTrace = asyncStackTrace.parent;
+  }
+  InspectorTest.log('');
+  Protocol.Debugger.resume();
+});
+
+Protocol.Debugger.enable();
+Protocol.Debugger.setAsyncCallStackDepth({ maxDepth: 128 });
+Protocol.Runtime.evaluate({ expression: 'test()//# sourceURL=expr.js',
+    awaitPromise: true })
+  .then(() => Protocol.Runtime.evaluate({ expression: 'gc()'}))
+  .then(InspectorTest.completeTest);