chore(DRAFT): use acorn, estree and esrap

[manuel3108]

Closes #94
Closes #44

Benefits

• closer to other tools in the svelte ecosystem
• Faster bundling (~33% speed improvement locally from 3s to 2s)
• Smaller bundle (not tested, but dropping babel should dramatically decrease the bundle size)
• more consistent formatting
• we are in full control of the printing, as we own esrap

Downsides

• Potentially to consistent formatting, as it looks like it's completely ignore the user input (tabs vs spaces, etc), but that's probably fixable in esrap
• Custom typing for special typescript types (see packages/ast-tooling/ts-estree.ts) and add typescript support Rich-Harris/esrap#13 for reasoning and considered alternatives.

Depends on Rich-Harris/esrap#13. Currently published as esrap-typescript-temp for ease of use for testing. Otherwise, this would require using pnpm link locally with the branch mentioned before.

If we want to proceed with this (which i think we should), this needs to be done

• publish packages/ast-tooling/ts-estree.ts seperately so that it can also be used inside esrap. Later they should probably live inside acorn-typescript once we fork it
• make esrap understand what a TSModuleDeclaration is and how to print it
• update types inside esrap according to the types above. This will probably also require way more types in this new package
• merge the pr inside esrap and publish it
• fix todos
• Testing. I have done a few tests here and there and generally the formatting is way more consistent and matches what i would expect.

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pnpm add https://pkg.pr.new/sveltejs/cli/sv@100

commit: 53921b6

[benmccann]

publish packages/ast-tooling/ts-estree.ts seperately so that it can also be used inside esrap. Later they should probably live inside acorn-typescript once we fork it

I think it'd be preferrable to just duplicate it in the short-term than to add a dependency on ast-tooling from esrap. Hopefully that can be short-lived and we can just add it to the acorn-typescript fork like you suggest

update types inside esrap according to the types above. This will probably also require way more types in this new package

That would be nice, but I wouldn't necessarily block on it. It will be a huge cleanup just to get this done and get off of recast, so if there are some things left for followups that would be fine

[manuel3108]

I think it'd be preferrable to just duplicate it in the short-term than to add a dependency on ast-tooling from esrap. Hopefully that can be short-lived and we can just add it to the acorn-typescript fork like you suggest

I was thinking about a custom package just for those types, but copying over should also work, if we want proceed with this