In #89 I tried adding automatic caching of installed dependencies for Deno. But that PR makes the node_modules explode in size if added to Git, due to @actions/cache requiring a lot of subdependencies.

This PR adds bundling of the action code, which will reduce the impact by a lot (see below), since node_modules will no longer be cloned. If this PR is merged, it should make the remaining work on #89 trivial.

There's mostly pro's to using the approach in this PR (which works similarly to @actions/checkout and other GitHub created Actions), except that contributors to this action needs to run deno task build prior to committing any changes (or checks will fail in PRs).

Commits

1. Convert action source code to TS
2. Adds .vscode folder with setting enabling deno, formatting and linting
   • This was helpful during development, but I can remove it again if it's unwanted
3. Adds a build script and a workflow to ensure built code is committed to dist/

Action size

The amount of files cloned when action is checked out, main vs this PR:

Before

• 5.18 MB
• 738 files (724 from node_modules)
• 107 folders (103 from node_modules)

After

• 1.62 MB
• 16 files
• 6 folders

So bundling code should make it much quicker to clone and run actions, due to smaller amount of files to for Git to handle, as well as a single file being much quicker to run in Node.js over hundreds.

Bundler choice

I landed at using tsdown, which is using rolldown under the hood. Things I tried that did not work well:

• @deno/dnt: A had a lot of errors when I tried, and this also produces a lot of unnecessary files for this use-case (package.json, types, etc)
• esbuild + jsr:@luca/esbuild-deno-loader: This worked to produce CJS output, but trying to produce ESM did not go well. Though this approach is very nice in avoiding an install step and downloading/caching dependencies during bundling.
• tsdown + deno-vite-plugin: I tried to hack around making the vite plugin work (calling configResolved() manually), but had various issues and could not get this working in the end.

Finally, I gave up and used tsdown after just installing node_modules with Deno first. This worked well on the first try, and was quicker than the other options anyway. It also seems to work with ESM output without issues.