[fix] don't strip type="application/.." tags

[dummdidumm]

Fixes #6862

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[Rich-Harris]

This approach will work in 99% of scenarios but it makes me a little nervous — what we should really be doing is stripping lang from top-level <script> elements while ignoring any inside elements (including <svelte:head>). Is there a straightforward way to do that?

[dummdidumm]

svelte-preprocess transforms all script/style tags handed to it. Those tags are found through a Regex in Svelte core - so today more than the top level tags are transformed. Therefore, it would be inconcistent to only strip it from top level tags afterwards - it could theoretically produce bugs for people.

For Svelte 4 I'd like to rework the preprocessing by having a parser instead of a Regexp (that parser would make some assumptions about the form of the unpreprocessed code, balanced brackets etc) which would also help to preprocess mustache tags inside the markup so people could use TypeScript in there - but until we have that, the best we can do is string-checks.

[Rich-Harris]

Ah, got it. In that case the good-enough solution is good enough

[niktek]

Hi,

This seems to have broken our packaging for our project. It looks like there is no check on whether s4 contains a value before doing a startsWith in package/src/utils.js:55:34. When we run pnpm package we get the following:

> Cannot read properties of undefined (reading 'startsWith')
    at file:///Users/nik/code/skeleton/node_modules/.pnpm/@[email protected]_iprco5tylfmvffqgrvqxc46njy/node_modules/@sveltejs/package/src/utils.js:55:34
    at String.replace (<anonymous>)
    at strip_lang_tags (file:///Users/nik/code/skeleton/node_modules/.pnpm/@[email protected]_iprco5tylfmvffqgrvqxc46njy/node_modules/@sveltejs/package/src/utils.js:52:4)
    at process_file (file:///Users/nik/code/skeleton/node_modules/.pnpm/@[email protected]_iprco5tylfmvffqgrvqxc46njy/node_modules/@sveltejs/package/src/index.js:201:16)
    at async Module.build (file:///Users/nik/code/skeleton/node_modules/.pnpm/@[email protected]_iprco5tylfmvffqgrvqxc46njy/node_modules/@sveltejs/package/src/index.js:61:3)
    at async file:///Users/nik/code/skeleton/node_modules/.pnpm/@[email protected]_iprco5tylfmvffqgrvqxc46njy/node_modules/@sveltejs/package/src/cli.js:27:4

Looking at #6862 our project does nothing with application/ and I can't see any debug info as to what file in our project is making this check fail. It is managing to process a considerable amount of the project before it fails though.