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useSingleCaseStatement (since v1.0.0)

Diagnostic Category: lint/style/useSingleCaseStatement

Enforces switch clauses have a single statement, emits a quick fix wrapping the statements in a block.

Examples

Section titled Examples

Invalid

Section titled Invalid
switch (foo) {
    case true:
    case false:
        let foo = '';
        foo;
}
code-block.js:4:9 lint/style/useSingleCaseStatement  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ⚠ A switch clause should only have a single statement.
  
    2 │     case true:
    3 │     case false:
  > 4 │         let foo = '';
      │         ^^^^^^^^^^^^^
  > 5 │         foo;
      │         ^^^^
    6 │ }
    7 │ 
  
  ℹ Unsafe fix: Wrap the statements in a block.
  
    1 1 │   switch (foo) {
    2 2 │       case true:
    3   │ - ····case·false:
      3 │ + ····case·false:·{
    4 4 │           let foo = '';
    5   │ - ········foo;
      5 │ + ········foo;
      6 │ + ····}
    6 7 │   }
    7 8 │

Valid

Section titled Valid
switch (foo) {
    case true:
    case false: {
        let foo = '';
        foo;
    }
}
Section titled Related links