esbuild-plugin-transform-hook

Esbuild plugin to apply custom transformation hooks

Status

PoC

Problem

Esbuild and its plugins mostly focus on sources processing, but sometimes additional modifications is also necessary for dependencies or bundles:

• Polyfill injects: esbuild#2840, esbuild#3517, esbuild#3099
• Custom patches: esbuild#3360
• Dynamic banners: esbuild#3291
• Importable helpers: esbuild#1230, esbuild-plugin-extract-helpers

These features will be provided sooner or later, but for now we need a workaround to apply custom transforms.

Usage

import { build, BuildOptions } from 'esbuild'
import { transformHookPlugin } from 'esbuild-plugin-transform-hook'

const plugin = transformHookPlugin({
  hooks: [
    {
      on: 'load', // or 'end'
      pattern: /\.ts$/,
      transform: (source) => {
        return source.replace(/console\.log/g, 'console.error')
      },
      rename: (path) => {
        return path.replace(/\.ts$/, '.js')
      }
    }
  ],
  // optional first-level pattern, defaults to /.$/
  pattern: /^(?!.*\.html$)/, 
})
const config: BuildOptions = {
  entryPoints: ['index.ts'],
  outdir: 'target/cjs',
  plugins: [plugin],
  format: 'cjs',
}

await build(config)

License

MIT