assert_equal("foo.jpg", legal_file::change_extension("foo.png", "jpg")); } public function change_four_letter_extension_test() { $this->assert_equal("foo.flv", legal_file::change_extension("foo.mpeg", "flv")); } public function change_extension_with_no_extension_test() { $this->assert_equal("foo.flv", legal_file::change_extension("foo", "flv")); } public function change_extension_path_containing_dots_test() { $this->assert_equal( "/website/foo.com/VID_20120513_105421.jpg", legal_file::change_extension("/website/foo.com/VID_20120513_105421.mp4", "jpg")); } }