provide-multi-plugin.js

/*
 * A webpack plugin for specifying multiple dependencies for a single
 * variable.
 *
 * plugins: [
 *   new ProvideMultiPlugin({
 *     'gilt': [ 'internal.gilt_require', 'internal.require' ]
 *   })
 * ]
 *
 */
'use strict';

const webpack = require('webpack');
const ModuleParserHelpers = require('webpack/lib/ModuleParserHelpers');
const ConstDependency = require('webpack/lib/dependencies/ConstDependency');
const NullFactory = require('webpack/lib/NullFactory');

class ProvideMultiPlugin {
  constructor (definitions) {
    this.definitions = definitions;
  }

  apply (compiler) {
    compiler.plugin('compilation',(compilation) => {
      compilation.dependencyFactories.set(ConstDependency, new NullFactory());
      compilation.dependencyTemplates.set(ConstDependency, new ConstDependency.Template());
    });

    Object.keys(this.definitions).forEach((name) => {
      let requests = this.definitions[name],
      nameParts = name.split('.');

      if (!Array.isArray(requests)) {
        requests = [ requests ];
      }

      if(nameParts.length > 0) {
        nameParts.slice(1).forEach((_, i) => {
          let name = nameParts.slice(0, i + 1).join('.');
          compiler.parser.plugin('can-rename ' + name, function() {
            return true;
          });
        });
      }

      compiler.parser.plugin('expression ' + name, function (expr) {
        let nameIdentifier = name,
          scopedName = name.indexOf('.') >= 0;

        if(scopedName) {
          nameIdentifier = '__webpack_provided_' + name.replace(/\./g, '_dot_');
        }

        for(let request of requests) {
          if(!ModuleParserHelpers.addParsedVariable(this, nameIdentifier, 'require(' + JSON.stringify(request) + ')')) {
            return false;
          }
        }

        if(scopedName) {
          nameIdentifier = '__webpack_provided_' + name.replace(/\./g, '_dot_');

          let dep = new ConstDependency(nameIdentifier, expr.range);
          dep.loc = expr.loc;

          this.state.current.addDependency(dep);
        }

        return true;
      });
    }, this);
  }
};

module.exports = ProvideMultiPlugin;