Fix for issue 16967

tests/compiler/dart2js_extra/16967_test.dart

Index: tests/compiler/dart2js_extra/16967_test.dart
diff --git a/tests/compiler/dart2js_extra/16967_test.dart b/tests/compiler/dart2js_extra/16967_test.dart
new file mode 100644
index 0000000000000000000000000000000000000000..26d9df7449a9ae31812b714a5f37ee849f9ddb43
--- /dev/null
+++ b/tests/compiler/dart2js_extra/16967_test.dart
@@ -0,0 +1,30 @@
+// Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:expect/expect.dart';
+
+// Regression test for http://dartbug.com/16967
+// Tests type propagation of negation.
+
+void main() {
+  new Foo().test();
+}
+
+class Foo {
+  var scale = 1;
+
+  void test() {
+    var scaleX = scale;
+    var scaleY = scale;
+    var flipX = true;
+
+    if (flipX) {
+      scaleX = -scaleX;
+    }
+
+    Expect.equals('X: -1, Y: 1', 'X: $scaleX, Y: $scaleY');
+    Expect.equals('true', '${scaleX < 0}', '$scaleX < 0');
+    Expect.equals('false', '${scaleY < 0}', '$scaleY < 0');
+  }
+}