build: bundle recast

[antfu]

Install size from 8.5MB -> 5.2MB (mainly Babel), from 35 packages to 4 packages. Get rid of many es5 polyfills and ESM -> CJS -> ESM glues. Result in around 5% faster, tho the performance isn't very related to our use cases.

[pi0]

It is a nice idea btw have you tried with impact on nuxi final size with double bundling of babel stuff?

might worth to have a subpath with optional non bundled version.

[antfu]

Babel is not bundled. Only recast and ast-types are bundled from the source code, as their distribution targets Node 4 (es2015 and transpiled to CJS). This approach allows us to ship ESM directly without ESM -> CJS -> ESM convention.

[codecov]

Codecov Report

Merging #81 (56cb074) into main (0d65b23) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main      #81   +/-   ##
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  Coverage   92.40%   92.40%           
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  Files          23       23           
  Lines        1751     1751           
  Branches      322      322           
=======================================
  Hits         1618     1618           
  Misses        133      133           

[pi0]

Let's go ahead and introduce other improvements in next versions

[pi0]

Small notes:

assert: resolve(__dirname, 'stubs/assert/index.js'), this from build.config seems unused

Enabling rollup.esbuild.minify: true reduces bundle size from 640kB to 380kB!

[antfu]

After running pnpm pack, the size doesn't have that much different with gzip. I would think it would be better trade-off to avoid minification for better DX and debugging experience.

[pi0]

since we are not bundling babel stuff yet, yes it is not much different. anyway consider that when bundling more, the startup (and sometimes runtime) time also improves with modification + memory usage is always less.

[antfu]

Yeah, but I imagine we won't bundle Babel any sooner as it's quite big and commonly used, isn't it? I imagine we can bundle recast because it's a bit niche, and probably only used by magicast.

[pi0]

Sure. That's what I wanted to share with you later about babel ;)