alexzhang1030/eslint-plugin-command

Comment-as-command for one-off codemod with ESLint.

eslint-plugin-command

Comment-as-command for one-off codemod with ESLint.

Install

npm i eslint-plugin-command -D

In your flat config eslint.config.mjs:

// eslint.config.mjs
import command from 'eslint-plugin-command/config'

export default [
  // ... your other flat config
  command(),
]

Built-in Commands

to-function

Convert an arrow function to a standard function declaration.

Trigger with /// to-function comment (triple slashes) one line above the arrow function.

Triggers:

• /// to-function
• /// to-fn
• /// 2f

/// to-function
const foo = async (msg: string): void => {
  console.log(msg)
}

Will be converted to (the command comment will be removed along the way):

async function foo(msg: string): void {
  console.log(msg)
}

to-arrow

Convert a standard function declaration to an arrow function.

Triggers:

• /// to-arrow
• /// 2a

/// to-arrow
function foo(msg: string): void {
  console.log(msg)
}

Will be converted to:

const foo = (msg: string): void => {
  console.log(msg)
}

keep-sorted

Keep the object keys or array items sorted.

Triggers:

• /// keep-sorted
• // @keep-sorted

/// keep-sorted
const obj = {
  b: 2,
  a: 1,
  c: 3,
}

Will be converted to:

/// keep-sorted
const obj = {
  a: 1,
  b: 2,
  c: 3,
}

Different from the other commands, the comment will not be removed after transformation to keep the sorting.

to-for-each

Convert for-of/for-in loop to .forEach().

Triggers:

• /// to-for-each
• /// foreach

/// to-for-each
for (const item of items) {
  if (!item)
    continue
  console.log(item)
}

Will be converted to:

items.forEach((item) => {
  if (!item)
    return
  console.log(item)
})

For for-in loop:

/// to-for-each
for (const key in obj) {
  if (!obj[key])
    continue
  console.log(obj[key])
}

Will be converted to:

Object.keys(obj).forEach((key) => {
  if (!obj[key])
    return
  console.log(obj[key])
})

to-for-of

Convert .forEach() to for-of loop.

Triggers:

• /// to-for-of
• /// forof

/// to-for-of
items.forEach((item) => {
  if (!item)
    return
  console.log(item)
})

Will be converted to:

for (const item of items) {
  if (!item)
    continue
  console.log(item)
}

to-dynamic-import

Convert import statement to dynamic import.

Triggers:

• /// to-dynamic-import
• /// to-dynamic

/// to-dynamic-import
import bar, { foo } from './foo'

Will be converted to:

const { default: bar, foo } = await import('./foo')

Custom Commands

It's also possible to define your custom commands.

// eslint.config.mjs
import command from 'eslint-plugin-command/config'
import { builtinCommands, defineCommand } from 'eslint-plugin-command/commands'

const myCommand = defineCommand({
  name: 'my-command',
  // RegExp to match the command comment (without leading `//`)
  match: /^@my-command$/,
  action(context) {
    // Do something with the context
  },
})

export default [
  // ... your other flat config
  command({
    commands: [
      ...builtinCommands,
      myCommand,
    ]
  }),
]

You can refer to the built-in commands for examples.

Sponsors

License

MIT License © 2023-PRESENT Anthony Fu