index.js 8.15 KB
"use strict";

function asyncGeneratorStep(gen, resolve, reject, _next, _throw, key, arg) { try { var info = gen[key](arg); var value = info.value; } catch (error) { reject(error); return; } if (info.done) { resolve(value); } else { Promise.resolve(value).then(_next, _throw); } }

function _asyncToGenerator(fn) { return function () { var self = this, args = arguments; return new Promise(function (resolve, reject) { var gen = fn.apply(self, args); function _next(value) { asyncGeneratorStep(gen, resolve, reject, _next, _throw, "next", value); } function _throw(err) { asyncGeneratorStep(gen, resolve, reject, _next, _throw, "throw", err); } _next(undefined); }); }; }

let babel;

try {
  babel = require("@babel/core");
} catch (err) {
  if (err.code === "MODULE_NOT_FOUND") {
    err.message += "\n babel-loader@8 requires Babel 7.x (the package '@babel/core'). " + "If you'd like to use Babel 6.x ('babel-core'), you should install 'babel-loader@7'.";
  }

  throw err;
} // Since we've got the reverse bridge package at @babel/core@6.x, give
// people useful feedback if they try to use it alongside babel-loader.


if (/^6\./.test(babel.version)) {
  throw new Error("\n babel-loader@8 will not work with the '@babel/core@6' bridge package. " + "If you want to use Babel 6.x, install 'babel-loader@7'.");
}

const {
  version
} = require("../package.json");

const cache = require("./cache");

const transform = require("./transform");

const injectCaller = require("./injectCaller");

const schema = require("./schema");

const {
  isAbsolute
} = require("path");

const loaderUtils = require("loader-utils");

const validateOptions = require("schema-utils");

function subscribe(subscriber, metadata, context) {
  if (context[subscriber]) {
    context[subscriber](metadata);
  }
}

module.exports = makeLoader();
module.exports.custom = makeLoader;

function makeLoader(callback) {
  const overrides = callback ? callback(babel) : undefined;
  return function (source, inputSourceMap) {
    // Make the loader async
    const callback = this.async();
    loader.call(this, source, inputSourceMap, overrides).then(args => callback(null, ...args), err => callback(err));
  };
}

function loader(_x, _x2, _x3) {
  return _loader.apply(this, arguments);
}

function _loader() {
  _loader = _asyncToGenerator(function* (source, inputSourceMap, overrides) {
    const filename = this.resourcePath;
    let loaderOptions = loaderUtils.getOptions(this) || {};
    validateOptions(schema, loaderOptions, {
      name: "Babel loader"
    });

    if (loaderOptions.customize != null) {
      if (typeof loaderOptions.customize !== "string") {
        throw new Error("Customized loaders must be implemented as standalone modules.");
      }

      if (!isAbsolute(loaderOptions.customize)) {
        throw new Error("Customized loaders must be passed as absolute paths, since " + "babel-loader has no way to know what they would be relative to.");
      }

      if (overrides) {
        throw new Error("babel-loader's 'customize' option is not available when already " + "using a customized babel-loader wrapper.");
      }

      let override = require(loaderOptions.customize);

      if (override.__esModule) override = override.default;

      if (typeof override !== "function") {
        throw new Error("Custom overrides must be functions.");
      }

      overrides = override(babel);
    }

    let customOptions;

    if (overrides && overrides.customOptions) {
      const result = yield overrides.customOptions.call(this, loaderOptions, {
        source,
        map: inputSourceMap
      });
      customOptions = result.custom;
      loaderOptions = result.loader;
    } // Deprecation handling


    if ("forceEnv" in loaderOptions) {
      console.warn("The option `forceEnv` has been removed in favor of `envName` in Babel 7.");
    }

    if (typeof loaderOptions.babelrc === "string") {
      console.warn("The option `babelrc` should not be set to a string anymore in the babel-loader config. " + "Please update your configuration and set `babelrc` to true or false.\n" + "If you want to specify a specific babel config file to inherit config from " + "please use the `extends` option.\nFor more information about this options see " + "https://babeljs.io/docs/core-packages/#options");
    } // Standardize on 'sourceMaps' as the key passed through to Webpack, so that
    // users may safely use either one alongside our default use of
    // 'this.sourceMap' below without getting error about conflicting aliases.


    if (Object.prototype.hasOwnProperty.call(loaderOptions, "sourceMap") && !Object.prototype.hasOwnProperty.call(loaderOptions, "sourceMaps")) {
      loaderOptions = Object.assign({}, loaderOptions, {
        sourceMaps: loaderOptions.sourceMap
      });
      delete loaderOptions.sourceMap;
    }

    const programmaticOptions = Object.assign({}, loaderOptions, {
      filename,
      inputSourceMap: inputSourceMap || undefined,
      // Set the default sourcemap behavior based on Webpack's mapping flag,
      // but allow users to override if they want.
      sourceMaps: loaderOptions.sourceMaps === undefined ? this.sourceMap : loaderOptions.sourceMaps,
      // Ensure that Webpack will get a full absolute path in the sourcemap
      // so that it can properly map the module back to its internal cached
      // modules.
      sourceFileName: filename
    }); // Remove loader related options

    delete programmaticOptions.customize;
    delete programmaticOptions.cacheDirectory;
    delete programmaticOptions.cacheIdentifier;
    delete programmaticOptions.cacheCompression;
    delete programmaticOptions.metadataSubscribers;

    if (!babel.loadPartialConfig) {
      throw new Error(`babel-loader ^8.0.0-beta.3 requires @babel/core@7.0.0-beta.41, but ` + `you appear to be using "${babel.version}". Either update your ` + `@babel/core version, or pin you babel-loader version to 8.0.0-beta.2`);
    }

    const config = babel.loadPartialConfig(injectCaller(programmaticOptions, this.target));

    if (config) {
      let options = config.options;

      if (overrides && overrides.config) {
        options = yield overrides.config.call(this, config, {
          source,
          map: inputSourceMap,
          customOptions
        });
      }

      if (options.sourceMaps === "inline") {
        // Babel has this weird behavior where if you set "inline", we
        // inline the sourcemap, and set 'result.map = null'. This results
        // in bad behavior from Babel since the maps get put into the code,
        // which Webpack does not expect, and because the map we return to
        // Webpack is null, which is also bad. To avoid that, we override the
        // behavior here so "inline" just behaves like 'true'.
        options.sourceMaps = true;
      }

      const {
        cacheDirectory = null,
        cacheIdentifier = JSON.stringify({
          options,
          "@babel/core": transform.version,
          "@babel/loader": version
        }),
        cacheCompression = true,
        metadataSubscribers = []
      } = loaderOptions;
      let result;

      if (cacheDirectory) {
        result = yield cache({
          source,
          options,
          transform,
          cacheDirectory,
          cacheIdentifier,
          cacheCompression
        });
      } else {
        result = yield transform(source, options);
      } // TODO: Babel should really provide the full list of config files that
      // were used so that this can also handle files loaded with 'extends'.


      if (typeof config.babelrc === "string") {
        this.addDependency(config.babelrc);
      }

      if (result) {
        if (overrides && overrides.result) {
          result = yield overrides.result.call(this, result, {
            source,
            map: inputSourceMap,
            customOptions,
            config,
            options
          });
        }

        const {
          code,
          map,
          metadata
        } = result;
        metadataSubscribers.forEach(subscriber => {
          subscribe(subscriber, metadata, this);
        });
        return [code, map];
      }
    } // If the file was ignored, pass through the original content.


    return [source, inputSourceMap];
  });
  return _loader.apply(this, arguments);
}