unicorn/import-style

You can import most modules in several ways. If one file writes path.join() and the next writes join(), the same function has two names in your project, and a search finds only half of its uses. This rule lets you choose the import styles for a module and reports the others.

There are four styles:

Style	Looks like
`named`	`import { join } from "node:path"`
`default`	`import path from "node:path"`
`namespace`	`import * as path from "node:path"`
`unassigned`	`import "node:path"`

Without any options, path, node:path and chalk need a default import, and util and node:util need named imports. No other module is checked.

Configure#

Off by default. To turn it on:

bunfig.toml

[lint.rules]
"unicorn/import-style" = "error" # or "warn"

Every option, set to its default:

bunfig.toml

[lint.rules]
"unicorn/import-style" = ["error", {
  styles = {},
  extendDefaultStyles = true,
  checkImport = true,
  checkDynamicImport = true,
  checkRequire = true,
  checkExportFrom = false,
}]

Examples#

example.js2 problems

import { join } from "node:path";
import util from "node:util";

example.jsNo problems

import path from "node:path";
import { promisify } from "node:util";

require() and await import() are checked too. const path = require("path") is accepted wherever a default import is. const path = await import("path") is a namespace import.

example.js2 problems

const { join } = require("path");
const chalk = await import("chalk");

example.jsNo problems

const path = require("path");
const { default: chalk } = await import("chalk");
const { promisify } = await import("node:util");

Options#

Option	Default	What it does
`styles`	`{}`	For each module name, the styles you allow (`true`) or forbid (`false`). `false` instead of an object turns off the check for that module.
`extendDefaultStyles`	`true`	Keep the default styles for `path`, `util` and `chalk`, and merge `styles` into them.
`checkImport`	`true`	Check `import` declarations.
`checkDynamicImport`	`true`	Check `import()`.
`checkRequire`	`true`	Check `require()`.
`checkExportFrom`	`false`	Also check `export ... from`.

bunfig.toml

[lint.rules]
"unicorn/import-style" = ["error", { styles = { react = { named = true } } }]

example.jswith { "styles": { "react": { "named": true } } }1 problem

import React from "react";

example.jswith { "styles": { "react": { "named": true } } }No problems

import { useState } from "react";

Anything you set for path, util or chalk is added to the defaults. This allows a default import of node:util and still allows named imports. Add "named": false to forbid those.

example.jswith { "styles": { "node:util": { "default": true } } }No problems

import util from "node:util";
import { promisify } from "node:util";

false turns a module off:

example.jswith { "styles": { "node:path": false } }No problems

import { join } from "node:path";

With checkExportFrom:

example.jswith { "checkExportFrom": true }1 problem

export { join } from "node:path";