---
source: crates/biome_js_analyze/tests/spec_tests.rs
expression: invalid.js
---
# Input
```jsx
var a = 1;
switch (a) {
	case 1:
		break;
	case 1:
		break;
	case 2:
		break;
	default:
		break;
}
var a = "1";
switch (a) {
	case "1":
		break;
	case "1":
		break;
	case "2":
		break;
	default:
		break;
}
var a = 1,
	one = 1;
switch (a) {
	case one:
		break;
	case one:
		break;
	case 2:
		break;
	default:
		break;
}
var a = 1,
	p = { p: { p1: 1, p2: 1 } };
switch (a) {
	case p.p.p1:
		break;
	case p.p.p1:
		break;
	default:
		break;
}
var a = 1,
	f = function (b) {
		return b ? { p1: 1 } : { p1: 2 };
	};
switch (a) {
	case f(true).p1:
		break;
	case f(true).p1:
		break;
	default:
		break;
}
var a = 1,
	f = function (s) {
		return { p1: s };
	};
switch (a) {
	case f(a + 1).p1:
		break;
	case f(a + 1).p1:
		break;
	default:
		break;
}
var a = 1,
	f = function (s) {
		return { p1: s };
	};
switch (a) {
	case f(a === 1 ? 2 : 3).p1:
		break;
	case f(a === 1 ? 2 : 3).p1:
		break;
	default:
		break;
}
var a = 1,
	f1 = function () {
		return { p1: 1 };
	};
switch (a) {
	case f1().p1:
		break;
	case f1().p1:
		break;
	default:
		break;
}
var a = [1, 2];
switch (a.toString()) {
	case [1, 2].toString():
		break;
	case [1, 2].toString():
		break;
	default:
		break;
}
switch (a) {
	case a:
	case a:
}
switch (a) {
	case a:
		break;
	case b:
		break;
	case a:
		break;
	case c:
		break;
	case a:
		break;
}
var a = 1,
	p = { p: { p1: 1, p2: 1 } };
switch (a) {
	case p.p.p1:
		break;
	case p.p.p1: // comment\n
		break;
	default:
		break;
}
var a = 1,
	p = { p: { p1: 1, p2: 1 } };
switch (a) {
	case /* comment */
	p.p.p1:
		break;
	case p.p.p1:
		break;
	default:
		break;
}
var a = 1,
	p = { p: { p1: 1, p2: 1 } };
switch (a) {
	case p.p /* comment */.p1:
		break;
	case p.p.p1: // comment
		break;
	default:
		break;
}
var a = 1,
	p = { p: { p1: 1, p2: 1 } };
switch (a) {
	case p.p.p1:
		break;
	case p.p.p1: // comment
		break;
	case /* comment */
	p.p.p1:
		break;
	default:
		break;
}
var a = 1,
	f = function (s) {
		return { p1: s };
	};
switch (a) {
	case f(a + 1).p1:
		break;
	case f(a + 1).p1:
		break;
	default:
		break;
}
var a = 1,
	f = function (s) {
		return { p1: s };
	};
switch (a) {
	case f(
		a + 1 // comment
	).p1:
		break;
	case f(a + 1).p1:
		break;
	default:
		break;
}

```

# Diagnostics
```
invalid.js:5:7 lint/suspicious/noDuplicateCase ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Duplicate case label.
  
    3 │ 	case 1:
    4 │ 		break;
  > 5 │ 	case 1:
      │ 	     ^
    6 │ 		break;
    7 │ 	case 2:
  
  i The first similar label is here:
  
    1 │ var a = 1;
    2 │ switch (a) {
  > 3 │ 	case 1:
      │ 	     ^
    4 │ 		break;
    5 │ 	case 1:
  

```

```
invalid.js:16:7 lint/suspicious/noDuplicateCase ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Duplicate case label.
  
    14 │ 	case "1":
    15 │ 		break;
  > 16 │ 	case "1":
       │ 	     ^^^
    17 │ 		break;
    18 │ 	case "2":
  
  i The first similar label is here:
  
    12 │ var a = "1";
    13 │ switch (a) {
  > 14 │ 	case "1":
       │ 	     ^^^
    15 │ 		break;
    16 │ 	case "1":
  

```

```
invalid.js:28:7 lint/suspicious/noDuplicateCase ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Duplicate case label.
  
    26 │ 	case one:
    27 │ 		break;
  > 28 │ 	case one:
       │ 	     ^^^
    29 │ 		break;
    30 │ 	case 2:
  
  i The first similar label is here:
  
    24 │ 	one = 1;
    25 │ switch (a) {
  > 26 │ 	case one:
       │ 	     ^^^
    27 │ 		break;
    28 │ 	case one:
  

```

```
invalid.js:40:7 lint/suspicious/noDuplicateCase ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Duplicate case label.
  
    38 │ 	case p.p.p1:
    39 │ 		break;
  > 40 │ 	case p.p.p1:
       │ 	     ^^^^^^
    41 │ 		break;
    42 │ 	default:
  
  i The first similar label is here:
  
    36 │ 	p = { p: { p1: 1, p2: 1 } };
    37 │ switch (a) {
  > 38 │ 	case p.p.p1:
       │ 	     ^^^^^^
    39 │ 		break;
    40 │ 	case p.p.p1:
  

```

```
invalid.js:52:7 lint/suspicious/noDuplicateCase ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Duplicate case label.
  
    50 │ 	case f(true).p1:
    51 │ 		break;
  > 52 │ 	case f(true).p1:
       │ 	     ^^^^^^^^^^
    53 │ 		break;
    54 │ 	default:
  
  i The first similar label is here:
  
    48 │ 	};
    49 │ switch (a) {
  > 50 │ 	case f(true).p1:
       │ 	     ^^^^^^^^^^
    51 │ 		break;
    52 │ 	case f(true).p1:
  

```

```
invalid.js:64:7 lint/suspicious/noDuplicateCase ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Duplicate case label.
  
    62 │ 	case f(a + 1).p1:
    63 │ 		break;
  > 64 │ 	case f(a + 1).p1:
       │ 	     ^^^^^^^^^^^
    65 │ 		break;
    66 │ 	default:
  
  i The first similar label is here:
  
    60 │ 	};
    61 │ switch (a) {
  > 62 │ 	case f(a + 1).p1:
       │ 	     ^^^^^^^^^^^
    63 │ 		break;
    64 │ 	case f(a + 1).p1:
  

```

```
invalid.js:76:7 lint/suspicious/noDuplicateCase ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Duplicate case label.
  
    74 │ 	case f(a === 1 ? 2 : 3).p1:
    75 │ 		break;
  > 76 │ 	case f(a === 1 ? 2 : 3).p1:
       │ 	     ^^^^^^^^^^^^^^^^^^^^^
    77 │ 		break;
    78 │ 	default:
  
  i The first similar label is here:
  
    72 │ 	};
    73 │ switch (a) {
  > 74 │ 	case f(a === 1 ? 2 : 3).p1:
       │ 	     ^^^^^^^^^^^^^^^^^^^^^
    75 │ 		break;
    76 │ 	case f(a === 1 ? 2 : 3).p1:
  

```

```
invalid.js:88:7 lint/suspicious/noDuplicateCase ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Duplicate case label.
  
    86 │ 	case f1().p1:
    87 │ 		break;
  > 88 │ 	case f1().p1:
       │ 	     ^^^^^^^
    89 │ 		break;
    90 │ 	default:
  
  i The first similar label is here:
  
    84 │ 	};
    85 │ switch (a) {
  > 86 │ 	case f1().p1:
       │ 	     ^^^^^^^
    87 │ 		break;
    88 │ 	case f1().p1:
  

```

```
invalid.js:97:7 lint/suspicious/noDuplicateCase ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Duplicate case label.
  
    95 │ 	case [1, 2].toString():
    96 │ 		break;
  > 97 │ 	case [1, 2].toString():
       │ 	     ^^^^^^^^^^^^^^^^^
    98 │ 		break;
    99 │ 	default:
  
  i The first similar label is here:
  
    93 │ var a = [1, 2];
    94 │ switch (a.toString()) {
  > 95 │ 	case [1, 2].toString():
       │ 	     ^^^^^^^^^^^^^^^^^
    96 │ 		break;
    97 │ 	case [1, 2].toString():
  

```

```
invalid.js:104:7 lint/suspicious/noDuplicateCase ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Duplicate case label.
  
    102 │ switch (a) {
    103 │ 	case a:
  > 104 │ 	case a:
        │ 	     ^
    105 │ }
    106 │ switch (a) {
  
  i The first similar label is here:
  
    101 │ }
    102 │ switch (a) {
  > 103 │ 	case a:
        │ 	     ^
    104 │ 	case a:
    105 │ }
  

```

```
invalid.js:111:7 lint/suspicious/noDuplicateCase ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Duplicate case label.
  
    109 │ 	case b:
    110 │ 		break;
  > 111 │ 	case a:
        │ 	     ^
    112 │ 		break;
    113 │ 	case c:
  
  i The first similar label is here:
  
    105 │ }
    106 │ switch (a) {
  > 107 │ 	case a:
        │ 	     ^
    108 │ 		break;
    109 │ 	case b:
  

```

```
invalid.js:115:7 lint/suspicious/noDuplicateCase ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Duplicate case label.
  
    113 │ 	case c:
    114 │ 		break;
  > 115 │ 	case a:
        │ 	     ^
    116 │ 		break;
    117 │ }
  
  i The first similar label is here:
  
    105 │ }
    106 │ switch (a) {
  > 107 │ 	case a:
        │ 	     ^
    108 │ 		break;
    109 │ 	case b:
  

```

```
invalid.js:123:7 lint/suspicious/noDuplicateCase ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Duplicate case label.
  
    121 │ 	case p.p.p1:
    122 │ 		break;
  > 123 │ 	case p.p.p1: // comment\n
        │ 	     ^^^^^^
    124 │ 		break;
    125 │ 	default:
  
  i The first similar label is here:
  
    119 │ 	p = { p: { p1: 1, p2: 1 } };
    120 │ switch (a) {
  > 121 │ 	case p.p.p1:
        │ 	     ^^^^^^
    122 │ 		break;
    123 │ 	case p.p.p1: // comment\n
  

```

```
invalid.js:134:7 lint/suspicious/noDuplicateCase ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Duplicate case label.
  
    132 │ 	p.p.p1:
    133 │ 		break;
  > 134 │ 	case p.p.p1:
        │ 	     ^^^^^^
    135 │ 		break;
    136 │ 	default:
  
  i The first similar label is here:
  
    130 │ switch (a) {
    131 │ 	case /* comment */
  > 132 │ 	p.p.p1:
        │ 	^^^^^^
    133 │ 		break;
    134 │ 	case p.p.p1:
  

```

```
invalid.js:144:7 lint/suspicious/noDuplicateCase ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Duplicate case label.
  
    142 │ 	case p.p /* comment */.p1:
    143 │ 		break;
  > 144 │ 	case p.p.p1: // comment
        │ 	     ^^^^^^
    145 │ 		break;
    146 │ 	default:
  
  i The first similar label is here:
  
    140 │ 	p = { p: { p1: 1, p2: 1 } };
    141 │ switch (a) {
  > 142 │ 	case p.p /* comment */.p1:
        │ 	     ^^^^^^^^^^^^^^^^^^^^
    143 │ 		break;
    144 │ 	case p.p.p1: // comment
  

```

```
invalid.js:154:7 lint/suspicious/noDuplicateCase ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Duplicate case label.
  
    152 │ 	case p.p.p1:
    153 │ 		break;
  > 154 │ 	case p.p.p1: // comment
        │ 	     ^^^^^^
    155 │ 		break;
    156 │ 	case /* comment */
  
  i The first similar label is here:
  
    150 │ 	p = { p: { p1: 1, p2: 1 } };
    151 │ switch (a) {
  > 152 │ 	case p.p.p1:
        │ 	     ^^^^^^
    153 │ 		break;
    154 │ 	case p.p.p1: // comment
  

```

```
invalid.js:157:2 lint/suspicious/noDuplicateCase ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Duplicate case label.
  
    155 │ 		break;
    156 │ 	case /* comment */
  > 157 │ 	p.p.p1:
        │ 	^^^^^^
    158 │ 		break;
    159 │ 	default:
  
  i The first similar label is here:
  
    150 │ 	p = { p: { p1: 1, p2: 1 } };
    151 │ switch (a) {
  > 152 │ 	case p.p.p1:
        │ 	     ^^^^^^
    153 │ 		break;
    154 │ 	case p.p.p1: // comment
  

```

```
invalid.js:169:7 lint/suspicious/noDuplicateCase ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Duplicate case label.
  
    167 │ 	case f(a + 1).p1:
    168 │ 		break;
  > 169 │ 	case f(a + 1).p1:
        │ 	     ^^^^^^^^^^^
    170 │ 		break;
    171 │ 	default:
  
  i The first similar label is here:
  
    165 │ 	};
    166 │ switch (a) {
  > 167 │ 	case f(a + 1).p1:
        │ 	     ^^^^^^^^^^^
    168 │ 		break;
    169 │ 	case f(a + 1).p1:
  

```

```
invalid.js:183:7 lint/suspicious/noDuplicateCase ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Duplicate case label.
  
    181 │ 	).p1:
    182 │ 		break;
  > 183 │ 	case f(a + 1).p1:
        │ 	     ^^^^^^^^^^^
    184 │ 		break;
    185 │ 	default:
  
  i The first similar label is here:
  
    177 │ 	};
    178 │ switch (a) {
  > 179 │ 	case f(
        │ 	     ^^
  > 180 │ 		a + 1 // comment
  > 181 │ 	).p1:
        │ 	^^^^
    182 │ 		break;
    183 │ 	case f(a + 1).p1:
  

```