Documentations about testing

[mgallego]

Hi,
The first of all: Thank to everybody for the mode, I've been using it for a long time.

At this moment I'm trying to learn some of emacs lisp, and I'm thinking in practice with a mode that I use, for example this one, but I have some doubts with the testing.

What is a php.face file? Exists any documentation about how to test and how you develop this mode?

Thank.

PS: I don't know how to set a "question" tag and if this is the right place to ask.

[zonuexe]

@mgallego
Hi, I'm sorry I missed your question for a week and a half.

The .php.face file is a serialized list of file contents and "Face".
This is related to code coloring: it is called “Text Property” "Face" in Emacs terms.
In general, major mode for programming is realized by a mechanism called font-lock-mode.

The regression test is realized by comparing this file with the actual rendering result.
Its core feature is php-mode-test--buffer-face-list and php-mode-test--parse-list-file.

From ERT, we just compare the serialized list to the file and the result of actually coloring the PHP script. Therefore, there are some problems with test visibility.

---

Also, generating .php.face files from PHP files requires some manual work.
I'm generating a “faces list” (list of propertized text) with the following steps:

1. Load the php-mode-test--buffer-face-list function from php-mode-test.el.
2. Open the target test file in PHP-mode.
   • At this time, disable some minor modes that cause distracting coloring.
     In my Emacs environment:
     • highlight-indent-guides-mode
     • idle-highlight-mode
3. Press M-: (or M-x eval-expression and input (setq x (php-mode-test--buffer-face-list (current-buffer))))
4. Execute M-x ielm and input x and press RET.
   • I use ielm because its pretty print is the easiest to use and has good visibility
5. Copy (yank / kill) the output into the .php.faces file.

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This is information that should generally be included in CONTRIBUTING.md, but I have neglected to describe it for a long time.

Please feel free to ask any questions about this test method.