Make exceptions propagate through multiple Future branches.

tests/corelib/future_test.dart

Index: tests/corelib/future_test.dart
diff --git a/tests/corelib/future_test.dart b/tests/corelib/future_test.dart
index 9ed1db54ed8a38e398b61fb2691a54d1067b8f12..1916dddfeddb9e0b68c331cf44b5835a13689713 100644
--- a/tests/corelib/future_test.dart
+++ b/tests/corelib/future_test.dart
@@ -565,6 +565,92 @@ testTransformExceptionReturnsAFuture() {
   Expect.equals("transformed value", transformedFuture.value);
 }
 
+// Tests for branching exceptions
+
+testExceptionTravelsAlongBothBranches() {
+  var results = <int>[];
+
+  var completer = new Completer();
+  var branch1 = completer.future.transform((_) => null);
+  var branch2 = completer.future.transform((_) => null);
+
+  branch1.handleException((e) {
+    results.add(1);
+    return true;
+  });
+
+  branch2.handleException((e) {
+    results.add(2);
+    return true;
+  });
+
+  completer.completeException("error");
+  Expect.setEquals([1, 2], results);
+}
+
+testExceptionTravelsAlongBothBranchesAfterComplete() {
+  var results = <int>[];
+
+  var completer = new Completer();
+  completer.completeException("error");
+
+  var branch1 = completer.future.transform((_) => null);
+  var branch2 = completer.future.transform((_) => null);
+
+  branch1.handleException((e) {
+    results.add(1);
+    return true;
+  });
+
+  branch2.handleException((e) {
+    results.add(2);
+    return true;
+  });
+
+  Expect.setEquals([1, 2], results);
+}
+
+testExceptionIsHandledInBaseAndBranch() {
+  var results = <String>[];
+
+  var completer = new Completer();
+  var branch = completer.future.transform((_) => null);
+
+  completer.future.handleException((e) {
+    results.add("base");
+    return true;
+  });
+
+  branch.handleException((e) {
+    results.add("branch");
+    return true;
+  });
+
+  completer.completeException("error");
+  Expect.setEquals(["base", "branch"], results);
+}
+
+testExceptionIsHandledInBaseAndBranchAfterComplete() {
+  var results = <String>[];
+
+  var completer = new Completer();
+  completer.completeException("error");
+
+  var branch = completer.future.transform((_) => null);
+
+  completer.future.handleException((e) {
+    results.add("base");
+    return true;
+  });
+
+  branch.handleException((e) {
+    results.add("branch");
+    return true;
+  });
+
+  Expect.setEquals(["base", "branch"], results);
+}
+
 main() {
   testImmediate();
   testNeverComplete();
@@ -605,4 +691,8 @@ main() {
   testTransformExceptionThrows();
   testTransformExceptionReturns();
   testTransformExceptionReturnsAFuture();
+  testExceptionTravelsAlongBothBranches();
+  testExceptionTravelsAlongBothBranchesAfterComplete();
+  testExceptionIsHandledInBaseAndBranch();
+  testExceptionIsHandledInBaseAndBranchAfterComplete();
 }