---
source: crates/biome_js_analyze/tests/spec_tests.rs
expression: invalid.jsonc
---
# Input
```cjs
!1 in [1,2];
```

# Diagnostics
```
invalid.jsonc:1:1 lint/suspicious/noUnsafeNegation  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! The negation operator is used unsafely on the left side of this binary expression.
  
  > 1 │ !1 in [1,2];
      │ ^^^^^^^^^^^
  
  i Unsafe fix: Wrap the expression with a parenthesis
  
    1 │ !(1·in·[1,2]);
      │  +          + 

```

# Input
```cjs
/**test*/!/** test*/1 instanceof [1,2];
```

# Diagnostics
```
invalid.jsonc:1:10 lint/suspicious/noUnsafeNegation  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! The negation operator is used unsafely on the left side of this binary expression.
  
  > 1 │ /**test*/!/** test*/1 instanceof [1,2];
      │          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  
  i Unsafe fix: Wrap the expression with a parenthesis
  
    1 │ /**test*/!/**·test*/(1·instanceof·[1,2]);
      │                     +                  + 

```