Function convertTargets

packages/vite/src/node/plugins/css.ts:3545–3586

(
  esbuildTarget: string | string[] | false,
)

  LightningCSSOptions['targets']
>()
export const convertTargets = (
  esbuildTarget: string | string[] | false,
): LightningCSSOptions['targets'] => {
  if (!esbuildTarget) return {}
  const cached = convertTargetsCache.get(esbuildTarget)
  if (cached) return cached
  const targets: LightningCSSOptions['targets'] = {}

  const entriesWithoutES = arraify(esbuildTarget).flatMap((e) => {
    const match = esRE.exec(e)
    if (!match) return e
    const year = match[1] === '6' ? 2015 : Number(match[1])
    if (!esMap[year]) throw new Error(`Unsupported target "${e}"`)
    return esMap[year]
  })

  for (const entry of entriesWithoutES) {
    if (entry === 'esnext') continue
    const index = entry.search(versionRE)
    if (index >= 0) {
      const browser = map[entry.slice(0, index)]
      if (browser === false) continue // No mapping available
      if (browser) {
        const [major, minor = 0] = entry
          .slice(index)
          .split('.')
          .map((v) => parseInt(v, 10))
        if (!isNaN(major) && !isNaN(minor)) {
          const version = (major << 16) | (minor << 8)
          if (!targets[browser] || version < targets[browser]!) {
            targets[browser] = version
          }
          continue
        }
      }
    }
    throw new Error(`Unsupported target "${entry}"`)
  }

  convertTargetsCache.set(esbuildTarget, targets)
  return targets
}

export function resolveLibCssFilename(
  libOptions: LibraryOptions,