migrateAutomaticVarInjection() — tailwindcss Function Reference

Source Code

packages/@tailwindcss-upgrade/src/codemods/template/migrate-automatic-var-injection.ts lines 8–74

export function migrateAutomaticVarInjection(
  designSystem: DesignSystem,
  _userConfig: Config | null,
  rawCandidate: string,
): string {
  for (let readonlyCandidate of designSystem.parseCandidate(rawCandidate)) {
    // The below logic makes extended use of mutation. Since candidates in the
    // DesignSystem are cached, we can't mutate them directly.
    let candidate = cloneCandidate(readonlyCandidate) as Writable<Candidate>

    let didChange = false

    // Add `var(…)` in modifier position, e.g.:
    //
    // `bg-red-500/[--my-opacity]` => `bg-red-500/[var(--my-opacity)]`
    if (
      'modifier' in candidate &&
      candidate.modifier?.kind === 'arbitrary' &&
      !isAutomaticVarInjectionException(designSystem, candidate, candidate.modifier.value)
    ) {
      let { value, didChange: modifierDidChange } = injectVar(candidate.modifier.value)
      candidate.modifier.value = value
      didChange ||= modifierDidChange
    }

    // Add `var(…)` to all variants, e.g.:
    //
    // `supports-[--test]:flex'` => `supports-[var(--test)]:flex`
    for (let variant of candidate.variants) {
      let didChangeVariant = injectVarIntoVariant(designSystem, variant)
      if (didChangeVariant) {
        didChange = true
      }
    }

    // Add `var(…)` to arbitrary candidates, e.g.:
    //
    // `[color:--my-color]` => `[color:var(--my-color)]`
    if (
      candidate.kind === 'arbitrary' &&
      !isAutomaticVarInjectionException(designSystem, candidate, candidate.value)
    ) {
      let { value, didChange: valueDidChange } = injectVar(candidate.value)
      candidate.value = value
      didChange ||= valueDidChange
    }

    // Add `var(…)` to arbitrary values for functional candidates, e.g.:
    //
    // `bg-[--my-color]` => `bg-[var(--my-color)]`
    if (
      candidate.kind === 'functional' &&
      candidate.value &&
      candidate.value.kind === 'arbitrary' &&
      !isAutomaticVarInjectionException(designSystem, candidate, candidate.value.value)
    ) {
      let { value, didChange: valueDidChange } = injectVar(candidate.value.value)
      candidate.value.value = value
      didChange ||= valueDidChange
    }

    if (didChange) {
      return designSystem.printCandidate(candidate)
    }
  }
  return rawCandidate
}