@vue/preload-webpack-plugin/src/lib/does-chunk-belong-to-html.js

A webpack plugin for injecting <link rel='preload|prefecth'> into HtmlWebpackPlugin pages, with async chunk support

/**
 * @license
 * Copyright 2018 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
const EntryPoint = require('webpack/lib/Entrypoint')

module.exports = function doesChunkBelongToHtml ({
  chunk,
  compilation,
  htmlPluginData,
  pluginOptions
}) {
  const chunkName = recursiveChunkEntryName(chunk)
  const options = htmlPluginData.plugin.options
  return isChunksFiltered(chunkName, options.chunks, options.excludeChunks)
}

// modify from html-webpack-plugin/index.js `filterChunks`
function isChunksFiltered (chunkName, includedChunks, excludedChunks) {
  // Skip if the chunks should be filtered and the given chunk was not added explicity
  if (Array.isArray(includedChunks) && includedChunks.indexOf(chunkName) === -1) {
    return false
  }
  // Skip if the chunks should be filtered and the given chunk was excluded explicity
  if (Array.isArray(excludedChunks) && excludedChunks.indexOf(chunkName) !== -1) {
    return false
  }
  // Add otherwise
  return true
}

function recursiveChunkEntryName (chunk) {
  const [chunkGroup] = chunk.groupsIterable
  return _recursiveChunkGroup(chunkGroup)
}

function _recursiveChunkGroup (chunkGroup) {
  if (chunkGroup instanceof EntryPoint) {
    return chunkGroup.name
  } else {
    const [chunkParent] = chunkGroup.getParents()
    return _recursiveChunkGroup(chunkParent)
  }
}