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useValidLang

Diagnostic Category: lint/a11y/useValidLang

Since: v1.0.0

Sources:

Description

Section titled Description

Ensure that the attribute passed to the lang attribute is a correct ISO language and/or country.

Examples

Section titled Examples

Invalid

Section titled Invalid
<html lang="lorem" />
code-block.jsx:1:12 lint/a11y/useValidLang ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Provide a valid value for the lang attribute.
  
  > 1 │ <html lang=“lorem” />
      │            ^^^^^^^
    2 │ 
  
  ℹ Some of valid languages:
  
  - ab
  - aa
  - af
  - sq
  - am
  - ar
  - an
  - hy
  - as
  - ay
  - az
  - ba
  - eu
  - bn
  - dz
  
<html lang="en-babab" />
code-block.jsx:1:12 lint/a11y/useValidLang ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Provide a valid value for the lang attribute.
  
  > 1 │ <html lang=“en-babab” />
      │            ^^^^^^^^^^
    2 │ 
  
  ℹ Some of valid countries:
  
  - AF
  - AL
  - DZ
  - AS
  - AD
  - AO
  - AI
  - AQ
  - AG
  - AR
  - AM
  - AW
  - AU
  - AT
  - AZ
  
<html lang="en-GB-typo" />
code-block.jsx:1:12 lint/a11y/useValidLang ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Provide a valid value for the lang attribute.
  
  > 1 │ <html lang=“en-GB-typo” />
      │            ^^^^^^^^^^^^
    2 │

Valid

Section titled Valid
<Html lang="en-babab" />

How to configure

Section titled How to configure
biome.json
{
  "linter": {
    "rules": {
      "a11y": {
        "useValidLang": "error"
      }
    }
  }
}
Section titled Related links