---
source: crates/biome_js_analyze/tests/spec_tests.rs
expression: invalid.js
---
# Input
```jsx
a += (a + b)

object.a += object.a + b;

a -= a - b

a *= a * b

a *= b * a

a /= a / b

a %= a % b

a **= a ** b

a >>= a >> b

a <<= a << b

a >>>= a >>> b

a &= a & b

a &= b & a

a |= a | b

a |= b | a

a ^= a ^ b

a ^= b ^ a


```

# Diagnostics
```
invalid.js:1:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Variable appears on both sides of an assignment operation.
  
  > 1 │ a += (a + b)
      │ ^^^^^^^^^^^^
    2 │ 
    3 │ object.a += object.a + b;
  
  i This assignment might be the result of a wrong refactoring.
  
  i Unsafe fix: Use a += b instead.
  
    1 │ a·+=·(a·+·b)
      │      ----- -

```

```
invalid.js:3:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Variable appears on both sides of an assignment operation.
  
    1 │ a += (a + b)
    2 │ 
  > 3 │ object.a += object.a + b;
      │ ^^^^^^^^^^^^^^^^^^^^^^^^
    4 │ 
    5 │ a -= a - b
  
  i This assignment might be the result of a wrong refactoring.
  
  i Unsafe fix: Use object.a += b instead.
  
    3 │ object.a·+=·object.a·+·b;
      │             -----------  

```

```
invalid.js:5:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Variable appears on both sides of an assignment operation.
  
    3 │ object.a += object.a + b;
    4 │ 
  > 5 │ a -= a - b
      │ ^^^^^^^^^^
    6 │ 
    7 │ a *= a * b
  
  i This assignment might be the result of a wrong refactoring.
  
  i Unsafe fix: Use a -= b instead.
  
    5 │ a·-=·a·-·b
      │      ---- 

```

```
invalid.js:7:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Variable appears on both sides of an assignment operation.
  
    5 │ a -= a - b
    6 │ 
  > 7 │ a *= a * b
      │ ^^^^^^^^^^
    8 │ 
    9 │ a *= b * a
  
  i This assignment might be the result of a wrong refactoring.
  
  i Unsafe fix: Use a *= b instead.
  
    7 │ a·*=·a·*·b
      │      ---- 

```

```
invalid.js:9:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Variable appears on both sides of an assignment operation.
  
     7 │ a *= a * b
     8 │ 
   > 9 │ a *= b * a
       │ ^^^^^^^^^^
    10 │ 
    11 │ a /= a / b
  
  i This assignment might be the result of a wrong refactoring.
  
  i Unsafe fix: Use a *= b instead.
  
    9 │ a·*=·b·*·a
      │       ----

```

```
invalid.js:11:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Variable appears on both sides of an assignment operation.
  
     9 │ a *= b * a
    10 │ 
  > 11 │ a /= a / b
       │ ^^^^^^^^^^
    12 │ 
    13 │ a %= a % b
  
  i This assignment might be the result of a wrong refactoring.
  
  i Unsafe fix: Use a /= b instead.
  
    11 │ a·/=·a·/·b
       │      ---- 

```

```
invalid.js:13:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Variable appears on both sides of an assignment operation.
  
    11 │ a /= a / b
    12 │ 
  > 13 │ a %= a % b
       │ ^^^^^^^^^^
    14 │ 
    15 │ a **= a ** b
  
  i This assignment might be the result of a wrong refactoring.
  
  i Unsafe fix: Use a %= b instead.
  
    13 │ a·%=·a·%·b
       │      ---- 

```

```
invalid.js:15:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Variable appears on both sides of an assignment operation.
  
    13 │ a %= a % b
    14 │ 
  > 15 │ a **= a ** b
       │ ^^^^^^^^^^^^
    16 │ 
    17 │ a >>= a >> b
  
  i This assignment might be the result of a wrong refactoring.
  
  i Unsafe fix: Use a **= b instead.
  
    15 │ a·**=·a·**·b
       │       ----- 

```

```
invalid.js:17:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Variable appears on both sides of an assignment operation.
  
    15 │ a **= a ** b
    16 │ 
  > 17 │ a >>= a >> b
       │ ^^^^^^^^^^^^
    18 │ 
    19 │ a <<= a << b
  
  i This assignment might be the result of a wrong refactoring.
  
  i Unsafe fix: Use a >>= b instead.
  
    17 │ a·>>=·a·>>·b
       │       ----- 

```

```
invalid.js:19:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Variable appears on both sides of an assignment operation.
  
    17 │ a >>= a >> b
    18 │ 
  > 19 │ a <<= a << b
       │ ^^^^^^^^^^^^
    20 │ 
    21 │ a >>>= a >>> b
  
  i This assignment might be the result of a wrong refactoring.
  
  i Unsafe fix: Use a <<= b instead.
  
    19 │ a·<<=·a·<<·b
       │       ----- 

```

```
invalid.js:21:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Variable appears on both sides of an assignment operation.
  
    19 │ a <<= a << b
    20 │ 
  > 21 │ a >>>= a >>> b
       │ ^^^^^^^^^^^^^^
    22 │ 
    23 │ a &= a & b
  
  i This assignment might be the result of a wrong refactoring.
  
  i Unsafe fix: Use a >>>= b instead.
  
    21 │ a·>>>=·a·>>>·b
       │        ------ 

```

```
invalid.js:23:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Variable appears on both sides of an assignment operation.
  
    21 │ a >>>= a >>> b
    22 │ 
  > 23 │ a &= a & b
       │ ^^^^^^^^^^
    24 │ 
    25 │ a &= b & a
  
  i This assignment might be the result of a wrong refactoring.
  
  i Unsafe fix: Use a &= b instead.
  
    23 │ a·&=·a·&·b
       │      ---- 

```

```
invalid.js:25:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Variable appears on both sides of an assignment operation.
  
    23 │ a &= a & b
    24 │ 
  > 25 │ a &= b & a
       │ ^^^^^^^^^^
    26 │ 
    27 │ a |= a | b
  
  i This assignment might be the result of a wrong refactoring.
  
  i Unsafe fix: Use a &= b instead.
  
    25 │ a·&=·b·&·a
       │       ----

```

```
invalid.js:27:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Variable appears on both sides of an assignment operation.
  
    25 │ a &= b & a
    26 │ 
  > 27 │ a |= a | b
       │ ^^^^^^^^^^
    28 │ 
    29 │ a |= b | a
  
  i This assignment might be the result of a wrong refactoring.
  
  i Unsafe fix: Use a |= b instead.
  
    27 │ a·|=·a·|·b
       │      ---- 

```

```
invalid.js:29:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Variable appears on both sides of an assignment operation.
  
    27 │ a |= a | b
    28 │ 
  > 29 │ a |= b | a
       │ ^^^^^^^^^^
    30 │ 
    31 │ a ^= a ^ b
  
  i This assignment might be the result of a wrong refactoring.
  
  i Unsafe fix: Use a |= b instead.
  
    29 │ a·|=·b·|·a
       │       ----

```

```
invalid.js:31:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Variable appears on both sides of an assignment operation.
  
    29 │ a |= b | a
    30 │ 
  > 31 │ a ^= a ^ b
       │ ^^^^^^^^^^
    32 │ 
    33 │ a ^= b ^ a
  
  i This assignment might be the result of a wrong refactoring.
  
  i Unsafe fix: Use a ^= b instead.
  
    31 │ a·^=·a·^·b
       │      ---- 

```

```
invalid.js:33:1 lint/suspicious/noMisrefactoredShorthandAssign  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! Variable appears on both sides of an assignment operation.
  
    31 │ a ^= a ^ b
    32 │ 
  > 33 │ a ^= b ^ a
       │ ^^^^^^^^^^
    34 │ 
  
  i This assignment might be the result of a wrong refactoring.
  
  i Unsafe fix: Use a ^= b instead.
  
    33 │ a·^=·b·^·a
       │       ----

```