noDuplicateJsxProps

JSX and TSX

Summary

• Rule available since: v1.0.0
• Diagnostic Category: lint/suspicious/noDuplicateJsxProps
• This rule is recommended, which means is enabled by default.
• This rule doesn’t have a fix.
• The default severity of this rule is error.
• Sources:
  • Same as react/jsx-no-duplicate-props

How to configure

biome.json

{
  "linter": {
    "rules": {
      "suspicious": {
        "noDuplicateJsxProps": "error"
      }
    }
  }
}

Description

Prevents JSX properties to be assigned multiple times.

Examples

Invalid

<Hello name="John" name="John" />

code-block.jsx:1:8 lint/suspicious/noDuplicateJsxProps ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ This JSX property is assigned multiple times.
  
  > 1 │ <Hello name=“John” name=“John” />
      │        ^^^^^^^^^^^
    2 │ 
  
  ℹ This attribute is assigned again here.
  
  > 1 │ <Hello name=“John” name=“John” />
      │                    ^^^^^^^^^^^
    2 │ 
  

<label xml:lang="en-US" xml:lang="en-US"></label>

code-block.jsx:1:8 lint/suspicious/noDuplicateJsxProps ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ This JSX property is assigned multiple times.
  
  > 1 │ <label xml:lang=“en-US” xml:lang=“en-US”></label>
      │        ^^^^^^^^^^^^^^^^
    2 │ 
  
  ℹ This attribute is assigned again here.
  
  > 1 │ <label xml:lang=“en-US” xml:lang=“en-US”></label>
      │                         ^^^^^^^^^^^^^^^^
    2 │ 
  

Valid

<Hello firstname="John" lastname="Doe" />

<label xml:lang="en-US" lang="en-US"></label>

Related links

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• Rule options
• Source Code
• Test Cases