noUselessReturn

JavaScript (and super languages)

Summary

Rule available since: v2.3.15
Diagnostic Category: lint/complexity/noUselessReturn
This rule isn’t recommended, so you need to enable it.
This rule has a safe fix.
The default severity of this rule is information.
Sources:
- Inspired from no-useless-return

How to configure

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{
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  "linter": {
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    "rules": {
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      "complexity": {
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        "noUselessReturn": "error"
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      }
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    }
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  }
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}

Description

Disallow redundant return statements.

A return; statement with nothing after it is redundant when it is the last reachable statement in a function body. Removing it does not change the function’s behavior, as execution naturally falls through to the end.

Examples

Invalid

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function foo() {
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    return;
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}

code-block.js:2:5 lint/complexity/noUselessReturn  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ℹ This return statement is unnecessary.
  
    1 │ function foo() {
  > 2 │     return;
      │     ^^^^^^^
    3 │ }
    4 │ 
  
  ℹ Removing this statement does not change the control flow of the function.
  
  ℹ Safe fix: Remove the unnecessary return statement.
  
    1 1 │   function foo() {
    2   │ - ····return;
    3 2 │   }
    4 3 │

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function foo() {
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    doSomething();
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    return;
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}

code-block.js:3:5 lint/complexity/noUselessReturn  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ℹ This return statement is unnecessary.
  
    1 │ function foo() {
    2 │     doSomething();
  > 3 │     return;
      │     ^^^^^^^
    4 │ }
    5 │ 
  
  ℹ Removing this statement does not change the control flow of the function.
  
  ℹ Safe fix: Remove the unnecessary return statement.
  
    1 1 │   function foo() {
    2 2 │       doSomething();
    3   │ - ····return;
    4 3 │   }
    5 4 │

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function foo() {
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    if (condition) {
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        bar();
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        return;
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    }
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}

code-block.js:4:9 lint/complexity/noUselessReturn  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ℹ This return statement is unnecessary.
  
    2 │     if (condition) {
    3 │         bar();
  > 4 │         return;
      │         ^^^^^^^
    5 │     }
    6 │ }
  
  ℹ Removing this statement does not change the control flow of the function.
  
  ℹ Safe fix: Remove the unnecessary return statement.
  
    2 2 │       if (condition) {
    3 3 │           bar();
    4   │ - ········return;
    5 4 │       }
    6 5 │   }

Valid

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function foo() {
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    return 5;
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}

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function foo() {
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    if (condition) {
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        return;
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    }
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    bar();
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}

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function foo() {
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    for (const x of xs) {
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        return;
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    }
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}