[WIP] Add swc JavaScript parser

[punkeel]

swc is a super-fast compiler written in rust; producing widely-supported javascript from modern standards and typescript.

Expose the swc parser in AST Explorer. This parser is built using Rust, and the client side version relies on WebAssembly.

Known bug: any action (editing the code or changing a setting) breaks the Autofocus feature, and requires a page reload.

Closes #555.

[gengjiawen]

Looks like npm moudle missing files.

ERROR in ./node_modules/@swc/wasm-web/wasm.js
Module not found: Error: Can't resolve './wasm_bg.js' in '/workspace/astexplorer/website/node_modules/@swc/wasm-web'
 @ ./node_modules/@swc/wasm-web/wasm.js 2:0-29 2:0-29
 @ ./src/parsers/js/transformers/swc/index.js
 @ ./src/parsers sync ^\.\/(?!utils|transpilers)[^/]+\/(transformers\/([^/]+)\/)?(codeExample\.txt|[^/]+?\.js)$
 @ ./src/parsers/index.js
 @ ./src/storage/gist.js
 @ ./src/app.js

[punkeel]

Yup, a new @swc/wasm-web release is required to fix it 😕

[punkeel]

Still not ok ;(

[gengjiawen]

Still not ok ;(

The publish npm is still broken, you can delete files in package.json and remove .gitignore in pkg folder.
My fork works (https://www.npmjs.com/package/@gengjiawen/swc).

[fkling]

What's the current state of this? Can I do anything to help? Or do you just want me to take a look at the parser wrapper?

[gengjiawen]

What's the current state of this? Can I do anything to help? Or do you just want me to take a look at the parser wrapper?

I think next release will swc will fix the build issue since the fix pr merged. Not sure the focus issue still exists ? @punkeel

[punkeel]

Hey there,

This PR is still blocked by @swc/wasm-web not containing the required files, hopefully this will be fixed with the next release. Once it's ready, I'll just update the package.json+yarn.lock files. I don't plan on changing the code in this PR in the foreseeable future, so reviews are welcome!

The focus issue still exists, the bug is reproducible across reloads/builds, just introduce Syntax Errors in the snippet, and the focus stops working until the page is reloaded. I haven't been able to pinpoint a reason for it.

[jdb8]

@punkeel hey, curious if @swc/wasm-web has now exposed what you need for this PR? I tried cloning it locally and bumping the package, but it seems like under webpack 4 (which astexplorer uses, at least in this branch), the way that the wasm lib is being imported doesn't work (they're using import.meta.url plus the URL() constructor which I think may have been added in webpack 5).

I can dig in more and google for workarounds but wondering if you were still interested in getting this merged - I think it'd be really useful as I and likely many others are starting to explore swc :)

Additionally - IMO something that would be really cool after this lands would be to support swc plugins in the transform section of ast explorer, so then it'd be feasible to prototype a full swc js plugin in-browser. UPDATE (2021-08-21): looks like the js plugin architecture is going to be deprecated, so this part probably doesn't make sense now (unless adding support for writing rust in-browser too!).

[punkeel]

Merged as part of f6a399b