Fixes#18431
The `~W(…)` syntax in Elixir is a _sigil_. It's basically another way to
write strings, arrays of strings, etc… The syntax lets you use a handful
of surrounding brackets like `~W(…)`, `~W[…]`, `~W{…}`, `~W"…"`, etc… to
let you write lists without necessarily having to escape characters.
In v3 our extractor was able to pick these up but in v4 Oxide does not.
I've added a preprocessor for Elixir files so we can modify the code
before our main extractor sees it.
Now things like this: `~W(text-white bg-gray-600)` will get turned into
` ~W text-white bg-gray-600 ` which can easily be processed by our
extractor.
The sigils we support are:
- `~s` / `~S` (strings)
- `~w` / `~W` (word lists)
- `~c` / `~C` (charlists)
We're specifically detecting the use of `(…)`, `[…]`, and `{…}` as using
quotes already works today.
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Co-authored-by: Robin Malfait <malfait.robin@gmail.com>