---
source: crates/biome_js_analyze/tests/spec_tests.rs
expression: inavlidSelfWrite.js
---
# Input
```jsx
let a = 1;

(a += 1);
export const e = ((a++), 5)

// object assignment pattern
let d, e; 
({d, e} = {d: 1, e: 2});

let f;
for(f = 0;; f++) {}
for(f = 0; cond; f++) {}

```

# Diagnostics
```
inavlidSelfWrite.js:1:5 lint/correctness/noUnusedVariables  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! This variable is unused.
  
  > 1 │ let a = 1;
      │     ^
    2 │ 
    3 │ (a += 1);
  
  i Unused variables usually are result of incomplete refactoring, typos and other source of bugs.
  
  i Unsafe fix: If this is intentional, prepend a with an underscore.
  
     1    │ - let·a·=·1;
        1 │ + let·_a·=·1;
     2  2 │   
     3    │ - (a·+=·1);
     4    │ - export·const·e·=·((a++),·5)
        3 │ + (_a·+=·1);
        4 │ + export·const·e·=·((_a++),·5)
     5  5 │   
     6  6 │   // object assignment pattern
  

```

```
inavlidSelfWrite.js:7:5 lint/correctness/noUnusedVariables  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! This variable is unused.
  
    6 │ // object assignment pattern
  > 7 │ let d, e;·
      │     ^
    8 │ ({d, e} = {d: 1, e: 2});
    9 │ 
  
  i Unused variables usually are result of incomplete refactoring, typos and other source of bugs.
  
  i Unsafe fix: If this is intentional, prepend d with an underscore.
  
     5  5 │   
     6  6 │   // object assignment pattern
     7    │ - let·d,·e;·
     8    │ - ({d,·e}·=·{d:·1,·e:·2});
        7 │ + let·_d,·e;·
        8 │ + ({_d,·e}·=·{d:·1,·e:·2});
     9  9 │   
    10 10 │   let f;
  

```

```
inavlidSelfWrite.js:7:8 lint/correctness/noUnusedVariables  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! This variable is unused.
  
    6 │ // object assignment pattern
  > 7 │ let d, e;·
      │        ^
    8 │ ({d, e} = {d: 1, e: 2});
    9 │ 
  
  i Unused variables usually are result of incomplete refactoring, typos and other source of bugs.
  
  i Unsafe fix: If this is intentional, prepend e with an underscore.
  
     5  5 │   
     6  6 │   // object assignment pattern
     7    │ - let·d,·e;·
     8    │ - ({d,·e}·=·{d:·1,·e:·2});
        7 │ + let·d,·_e;·
        8 │ + ({d,·_e}·=·{d:·1,·e:·2});
     9  9 │   
    10 10 │   let f;
  

```

```
inavlidSelfWrite.js:10:5 lint/correctness/noUnusedVariables  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! This variable is unused.
  
     8 │ ({d, e} = {d: 1, e: 2});
     9 │ 
  > 10 │ let f;
       │     ^
    11 │ for(f = 0;; f++) {}
    12 │ for(f = 0; cond; f++) {}
  
  i Unused variables usually are result of incomplete refactoring, typos and other source of bugs.
  
  i Unsafe fix: If this is intentional, prepend f with an underscore.
  
     8  8 │   ({d, e} = {d: 1, e: 2});
     9  9 │   
    10    │ - let·f;
    11    │ - for(f·=·0;;·f++)·{}
    12    │ - for(f·=·0;·cond;·f++)·{}
       10 │ + let·_f;
       11 │ + for(_f·=·0;;·_f++)·{}
       12 │ + for(_f·=·0;·cond;·_f++)·{}
    13 13 │   
  

```