fliphub-monorepo/modules-sub/flip-webpack-chain/src/Resolve.js

the builder of builders

const ChainedMap = require('./ChainedMap');
const ChainedSet = require('./ChainedSet');
const Plugin = require('./Plugin');
const merge = require('deepmerge');

module.exports = class extends ChainedMap {
  constructor(parent) {
    super(parent);
    this.alias = new ChainedMap(this);
    this.aliasFields = new ChainedSet(this);
    this.descriptionFiles = new ChainedSet(this);
    this.extensions = new ChainedSet(this);
    this.mainFields = new ChainedSet(this);
    this.mainFiles = new ChainedSet(this);
    this.modules = new ChainedSet(this);
    this.plugins = new ChainedMap(this);
    this.extend([
      'enforceExtension',
      'enforceModuleExtension',
      'unsafeCache',
      'symlinks',
      'cachePredicate'
    ]);
  }

  plugin(name) {
    if (!this.plugins.has(name)) {
      this.plugins.set(name, new Plugin(this));
    }

    return this.plugins.get(name);
  }

  toConfig() {
    return this.clean(Object.assign(this.entries() || {}, {
      alias: this.alias.entries(),
      aliasFields: this.aliasFields.values(),
      descriptionFiles: this.descriptionFiles.values(),
      extensions: this.extensions.values(),
      mainFields: this.mainFields.values(),
      mainFiles: this.mainFiles.values(),
      modules: this.modules.values(),
      plugins: this.plugins.values().map(plugin => plugin.toConfig())
    }));
  }

  merge(obj) {
    Object
      .keys(obj)
      .forEach(key => {
        const value = obj[key];

        switch (key) {
          case 'alias':
          case 'aliasFields':
          case 'descriptionFiles':
          case 'extensions':
          case 'mainFields':
          case 'mainFiles':
          case 'modules':
          case 'plugins': {
            return this[key].merge(value);
          }

          default: {
            if (this.has(key)) {
              this.set(key, merge(this.get(key), value));
            } else {
              this.set(key, value);
            }
          }
        }
      });

    return this;
  }
};