Use esbuild for tests and build

[johnrees]

Just a proposal, no worries if you don't think it's suitable for this project :)

Esbuild runs faster, simplifies the configuration a bit and wouldn't compile the project until (#8) was fixed. The node resolve plugin didn't seem to detect this issue.

npm run test

before
npm run test 3.26s user 0.68s system 125% cpu 3.140 total

after (using esbuild)
npm run test 2.20s user 0.67s system 107% cpu 2.669 total

npm run build

before
npm run build 3.21s user 0.56s system 173% cpu 2.174 total

after
npm run build 1.48s user 0.34s system 213% cpu 0.855 total

(using minify option instead of terser)
npm run build 0.44s user 0.10s system 103% cpu 0.521 total
created dist/index.mjs in 72ms

[johnrees]

perhaps experimental isn't the way to go for this particular project. I added an issue to the rollup plugin that I found with injecting env here egoist/rollup-plugin-esbuild#314

[koeninger]

Thanks for proposing this, couple of questions

• I'm not super familiar with esbuild, does it make more sense to have a separate wrangler template that's esbuild only, rather than rollup + esbuild?
• I'm a little concerned about the comment that it wouldn't compile with is-even but would with is-odd... I'd expect transitive dependencies to work. Do you have any more info on what the issue there was?