@Test
public void testOut() throws Exception {

  final String prog = "void f(out int x) { } void main() { int a; f(a); }";
  TranslationUnit tu = ParseHelper.parse(prog);
  List<SimplifyExprReductionOpportunity> ops = ExprToConstantReductionOpportunities
      .findOpportunities(MakeShaderJobFromFragmentShader.make(tu),
        new ReducerContext(true, ShadingLanguageVersion.ESSL_100,
      new RandomWrapper(0), new IdGenerator()));
  for (SimplifyExprReductionOpportunity op : ops) {
    op.applyReduction();
  }
  assertEquals(PrettyPrinterVisitor.prettyPrintAsString(ParseHelper.parse(prog)),
      PrettyPrinterVisitor.prettyPrintAsString(tu));
}