add wildcard support for web-mode-indentless-attributes

[jasalt]

Noted issue with JS libraries / frameworks like Datastar and AlpineJS where attribute value non-indenting rules cannot be easily applied to attributes that use modifiers such as data-on:<eventname> or x-on:<eventname> as only string matches are looked from web-mode-indentless-attributes.

With this edit, wildcard postfix is allowed for more flexible matching e.g. following which should match attributes starting with data-on::

(setq web-mode-indentless-attributes
      '("onclick" "onmouseover" "onmouseout" "onsubmit" "data-on:*"))

With quick testing this seems to work but am evaluating it further currently. Is this sort of feature something that would be feasible to include in web-mode @fxbois ?

Test setup / demo (Emacs 30.1):

config.el

(setq-default indent-tabs-mode nil)
(setopt inhibit-splash-screen t)

;; Load the patched web-mode.el
(load "/home/user/Desktop/web-mode-attr-wildcard/web-mode/web-mode.el")
(add-to-list 'auto-mode-alist '("\\.html?\\'" . web-mode))

;; Add custom rule to match data-on: attribute
(setq web-mode-indentless-attributes
      '("onclick" "onmouseover" "onmouseout" "onsubmit" "data-on:*"))

example.html

<div onclick="just {
                testing
              }"
     data-on:click="just {
                      testing
                    }"
     data-not-click="just {
              testing
              }"></div>

• onclick keeps manual indent (as it does by default)
• data-on:click follows same rule (matched by wildcard)
• data-not-click gets auto indented (normal behavior)

Run: emacs -q -l ./config.el ./example.html

[fxbois]

Would it be possible for you to test that it works with 29.x version of emacs ?

[jasalt]

@fxbois sure, I'll test it later next week.