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noUnusedImports (since v1.3.0)

Diagnostic Category: lint/nursery/noUnusedImports

Disallow unused imports.

Unused imports might be the result of an incomplete refactoring. The code fix can remove comments associated with an import. See the last invalid example.

Examples

Section titled Examples

Invalid

Section titled Invalid
import A from 'mod';
nursery/noUnusedImports.js:1:8 lint/nursery/noUnusedImports  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ⚠ This import is unused.
  
  > 1 │ import A from 'mod';
      │        ^
    2 │ 
  
  ℹ Unused imports might be the result of an incomplete refactoring.
  
  ℹ Safe fix: Remove the unused import.
  
    1   │ - import·A·from·'mod';
    2   │ - 
  

import * as A from 'mod';
nursery/noUnusedImports.js:1:13 lint/nursery/noUnusedImports  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ⚠ This import is unused.
  
  > 1 │ import * as A from 'mod';
      │             ^
    2 │ 
  
  ℹ Unused imports might be the result of an incomplete refactoring.
  
  ℹ Safe fix: Remove the unused import.
  
    1   │ - import·*·as·A·from·'mod';
    2   │ - 
  

import { type A, B } from 'mod';


export { B }
nursery/noUnusedImports.js:1:15 lint/nursery/noUnusedImports  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ⚠ This import is unused.
  
  > 1 │ import { type A, B } from 'mod';
      │               ^
    2 │ 
    3 │ export { B }
  
  ℹ Unused imports might be the result of an incomplete refactoring.
  
  ℹ Safe fix: Remove the unused import.
  
    1 │ import·{·type·A,·B·}·from·'mod';
      │          --------               

// Header comment
import /*inner comment */ A from 'mod'; // Associated comment


// Another header comment
import {
    // A's header comment
    type A, // A's comment
    // B's header comment
    B,
} from 'mod';


export { B }
nursery/noUnusedImports.js:7:5 parse ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ 'import { type x ident }' are a TypeScript only feature. Convert your file to a TypeScript file or remove the syntax.
  
    5 │ import {
    6 │     // A's header comment
  > 7 │     type A, // A's comment
      │     ^^^^^^
    8 │     // B's header comment
    9 │     B,
  
  ℹ TypeScript only syntax

Valid

Section titled Valid
import { A, type B } from 'mod';


function f(arg: B): A {
    return new A(arg);
}
Section titled Related links