@Test
public void testNothingToRemove() throws Exception {

  final String program = "void main() {\n"
      + "  float k = 1.0;\n"
      + "  gl_FragColor = vec4(k, 0.0, 0.0, 0.0);\n"
      + "}\n";
  final TranslationUnit tu = ParseHelper.parse(program);
  List<VariableDeclReductionOpportunity> ops = VariableDeclReductionOpportunities
      .findOpportunities(
          MakeShaderJobFromFragmentShader.make(tu),
          new ReducerContext(
              false,
              ShadingLanguageVersion.ESSL_100,
              new RandomWrapper(0),
              new IdGenerator())
      );
  assertEquals(0, ops.size());
}