---
source: crates/biome_js_analyze/tests/spec_tests.rs
expression: valid.js
---
# Input
```jsx
/^abc[a-zA-Z]/;
/^abc/;
/[\[]/;
/[\]]/;
/\[][\]]/;
/[a-zA-Z\[]/;
/[[]/;
/[\[a-z[]]/;
/[\-\[\]\/\{\}\(\)\*\+\?\.\\^\$\|]/g;
/\s*:\s*/gim;
/[\]]/uy;
/[\]]/s;
/[\]]/d;
/\[]/;
/[[^]]/v;
/[[\]]]/v;
/[[\[]]/v;
/[a--b]/v;
/[a&&b]/v;
/[[a][b]]/v;
/[\q{}]/v;
/[[^]--\p{ASCII}]/v;
/[\u200E\u2066-\u2069]/gu;
```

# Diagnostics
```
valid.js:15:3 lint/correctness/noEmptyCharacterClassInRegex ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! The regular expression includes this negated empty character class.
  
    13 │ /[\]]/d;
    14 │ /\[]/;
  > 15 │ /[[^]]/v;
       │   ^^^
    16 │ /[[\]]]/v;
    17 │ /[[\[]]/v;
  
  i Negated empty character classes match anything.
    If you want to match against [, escape it \[.
    Otherwise, remove the character class or fill it.
  

```

```
valid.js:22:3 lint/correctness/noEmptyCharacterClassInRegex ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ! The regular expression includes this negated empty character class.
  
    20 │ /[[a][b]]/v;
    21 │ /[\q{}]/v;
  > 22 │ /[[^]--\p{ASCII}]/v;
       │   ^^^
    23 │ /[\u200E\u2066-\u2069]/gu;
  
  i Negated empty character classes match anything.
    If you want to match against [, escape it \[.
    Otherwise, remove the character class or fill it.
  

```