Function buildKeyedFunctionsState

packages/nuxt/src/compiler/plugins/keyed-functions.ts:45–96

* Builds the lookup state from a list of keyed functions. * * Note: `namesToSourcesToFunctionMeta` is a global copy that maps exported names to sources. * It does NOT include local import renames — the transform handler builds per-file local * name mappings separately. The `source`s have resolve

(keyedFunctions: KeyedFunction[])

 * name mappings separately. The `source`s have resolved aliases and are without extensions.
 */
function buildKeyedFunctionsState (keyedFunctions: KeyedFunction[]) {
  const namesToSourcesToFunctionMeta = new Map<string, Map<string, BackwardsCompatibleKeyedFunction>>()
  // filenames (without extension) of files that have a `default` keyed function export
  const defaultExportSources = new Set<string>()

  for (const f of keyedFunctions) {
    let functionName = f.name
    const fnSource = typeof f.source === 'string' ? stripExtension(f.source) : ''

    if (f.name === 'default') {
      const parsedSource = parse(f.source)
      defaultExportSources.add(parsedSource.name)
      functionName = camelCase(parsedSource.name)
    }

    if (import.meta.dev) {
      const sourcesToFunctionMeta = namesToSourcesToFunctionMeta.get(functionName)
      const existingEntry = sourcesToFunctionMeta?.get(fnSource)
      if (existingEntry?.source && existingEntry.source === fnSource) {
        logger.warn(`[nuxt:compiler] [keyed-functions] Duplicate function name \`${functionName}\`${functionName !== f.name ? ` defined as \`${f.name}\`` : ''} with ${f.source ? `the same source \`${f.source}\`` : 'no source'} found. Overwriting the existing entry.`)
      }
    }

    let sourcesToFunctionMeta = namesToSourcesToFunctionMeta.get(functionName)
    if (!sourcesToFunctionMeta) {
      sourcesToFunctionMeta = new Map<string, KeyedFunction>()
      namesToSourcesToFunctionMeta.set(functionName, sourcesToFunctionMeta)
    }

    sourcesToFunctionMeta.set(fnSource, {
      ...f,
      // TODO: use only `fnSource` in Nuxt 5
      source: typeof f.source === 'string' ? fnSource : f.source,
    })
  }

  // resolved paths of all the sources WITHOUT EXTENSIONS
  const sources = new Set<string>()
  for (const sourcesToFunctionMeta of namesToSourcesToFunctionMeta.values()) {
    for (const f of sourcesToFunctionMeta.values()) {
      // TODO: remove check in Nuxt 5 (keeping it at the moment for the case when there is a RegExp in `source`)
      if (f.source && typeof f.source === 'string') {
        sources.add(f.source)
      }
    }
  }

  // TODO: come up with a better way to include files importing a `default` export (imported name can be arbitrary)
  const codeIncludeRE = new RegExp(`\\b(${[...namesToSourcesToFunctionMeta.keys(), ...defaultExportSources].map(f => escapeRE(f)).join('|')})\\b`)

  return { namesToSourcesToFunctionMeta, defaultExportSources, sources, codeIncludeRE }
}

export const KeyedFunctionsPlugin = (options: KeyedFunctionsOptions) => createUnplugin(() => {
  // Build initial state from the static keyedFunctions list