Make compile-time errors catchable

runtime/vm/dart_api_impl.cc

Index: runtime/vm/dart_api_impl.cc
diff --git a/runtime/vm/dart_api_impl.cc b/runtime/vm/dart_api_impl.cc
index ccda7f0d172d6666140b1b55016e06ce5106d367..7e3a401d285fc558e4b5ccad1c496633b9967c29 100644
--- a/runtime/vm/dart_api_impl.cc
+++ b/runtime/vm/dart_api_impl.cc
@@ -184,6 +184,18 @@ static RawInstance* GetMapInstance(Zone* zone, const Object& obj) {
 }
 
 
+static bool IsSyntaxErrorObject(Zone* zone, const Object& obj) {
+  Isolate* I = Thread::Current()->isolate();
+  const Class& error_class =
+      Class::Handle(I->object_store()->syntax_error_class());

[siva, 2016/09/15 18:11:45]

Handle(zone, I->object_store()....
as the zone seems to be passed in as a parameter.

[hausner, 2016/09/15 21:28:28]

Done.

+  ASSERT(!error_class.IsNull());
+  if (obj.GetClassId() == error_class.id()) {
+    return true;
+  }
+  return false;
+}
+
+
 static bool GetNativeStringArgument(NativeArguments* arguments,
                                     int arg_index,
                                     Dart_Handle* str,
@@ -761,6 +773,13 @@ DART_EXPORT bool Dart_IsUnhandledExceptionError(Dart_Handle object) {
 
 
 DART_EXPORT bool Dart_IsCompilationError(Dart_Handle object) {
+  if (Dart_IsUnhandledExceptionError(object)) {
+    DARTSCOPE(Thread::Current());
+    const UnhandledException& error =
+        UnhandledException::Cast(Object::Handle(Z, Api::UnwrapHandle(object)));
+    const Instance& exc = Instance::Handle(Z, error.exception());
+    return IsSyntaxErrorObject(Z, exc);
+  }
   return Api::ClassId(object) == kLanguageErrorCid;
 }