Edit

ESM

If you want to write your CLI or plugins using ESM you just need to make a few changes to your tsconfig.json and bin scripts.

1. Add the following options to the tsconfig.json in your project:

{
  "compilerOptions": {
    "module": "ES2020",
    "moduleResolution": "node",
  },
  "ts-node": {
    "esm": true
  }
}

2. Rename bin/dev to bin/dev.js and replace the contents with the following:

#!/usr/bin/env ts-node

/* eslint-disable node/shebang */

import oclif from '@oclif/core'
import path from 'node:path'
import url from 'node:url'
// eslint-disable-next-line node/no-unpublished-import
import {register} from 'ts-node'

// In dev mode -> use ts-node and dev plugins
process.env.NODE_ENV = 'development'

register({
  project: path.join(path.dirname(url.fileURLToPath(import.meta.url)), '..', 'tsconfig.json'),
})

// In dev mode, always show stack traces
oclif.settings.debug = true

// Start the CLI
oclif
.run(process.argv.slice(2), import.meta.url)
.then(oclif.flush)
.catch(oclif.Errors.handle)

3. Rename bin/run to bin/run.js and replace the contents with the following:

#!/usr/bin/env node

import oclif from '@oclif/core'

oclif
.run(process.argv.slice(2), import.meta.url)
.then(oclif.flush)
.catch(oclif.Errors.handle)

Alternatively, you can use the execute function to abstract out the bin scripts. You will still need to modify your tsconfig.json as documented above.

Example for ESM dev.js

#!/usr/bin/env ts-node
// eslint-disable-next-line node/shebang
(async () => {
  const oclif = await import('@oclif/core')
  await oclif.execute({type: 'esm', development: true, dir: import.meta.url})
})()

Example for ESM run.js

#!/usr/bin/env node
// eslint-disable-next-line node/shebang
(async () => {
  const oclif = await import('@oclif/core')
  await oclif.execute({type: 'esm', dir: import.meta.url})
})()

Example for CJS dev.js

#!/usr/bin/env node
// eslint-disable-next-line node/shebang
(async () => {
  const oclif = await import('@oclif/core')
  await oclif.execute({type: 'cjs', development: true, dir: __dirname})
})()

Example for CJS run.js

#!/usr/bin/env node
// eslint-disable-next-line node/shebang
(async () => {
  const oclif = await import('@oclif/core')
  await oclif.execute({type: 'cjs', dir: import.meta.url})
})()

3. Update the bin property in the package.json

Change

  "bin": {
    "my-cli": "./bin/run"
  },

to

  "bin": {
    "my-cli": "./bin/run.js"
  },

4. Update any other references to bin/dev and bin/run to bin/dev.js and bin/run.js

You may have references to the bin scripts in your .vscode/launch.json. You'll need to update these as well.