Most CSS keywords, functions,... are case insensitive

[romainmenke]

https://github.com/romainmenke/css-import-tests/blob/main/tests/001-core-features/case-sensitivity/001/style.css#L2

Browsers don't distinguish between

• @IMPORT url("a.css");
• @import url("a.css");

But this is not a lowercase match.

esbuild currently ignores @IMPORT and treats @import 'foo.css' LAYER SUPPORTS(display: grid) as media conditions.

I am only testing @import, but maybe there are other parts of esbuild that also need to handle keywords as case insensitive?

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Difference between case insensitive and lower case match :

// Not a regular 'K'
`blacK`.toLowerCase() === 'black' 
// true

/black/i.test(`blacK`)
// false

this might be obvious, but there are numerous bugs in PostCSS plugins because of this difference :)

[romainmenke]

Works now! Awesome!

---

I don't think my earlier comment about case insensitivity vs lower case matching was entirely correct.

It seems that somewhere in copy/pasting or maybe GitHub normalizing the specific char was lost.

A gist to generate all possible cases (there is only one) : https://gist.github.com/romainmenke/6a578290b240aa9ba3c6e726ecab96a4

The specific char code that produces the specific K : 8490