/**
  * Creates a ready to use function fixture.
  *
  * @param string $name Optional function name.
  * @return \PDepend\Source\AST\ASTFunction
  * @since 1.0.2
  */
 protected function createFunctionFixture($name = null)
 {
     $name = $name ? $name : get_class($this);
     $function = new ASTFunction($name);
     $function->setCompilationUnit(new ASTCompilationUnit($GLOBALS['argv'][0]));
     $function->setCache(new MemoryCacheDriver());
     $function->addChild(new ASTFormalParameters());
     return $function;
 }