create-expo-cljs-app/template/node_modules/metro/src/shared/output/RamBundle/as-assets.js

Create a react native application with Expo and Shadow-CLJS!

/**
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 *
 * @format
 */
"use strict";

const MAGIC_RAM_BUNDLE_NUMBER = require("./magic-number");

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

const mkdirp = require("mkdirp");

const path = require("path");

const relativizeSourceMapInline = require("../../../lib/relativizeSourceMap");

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

const writeSourceMap = require("./write-sourcemap");

const _require = require("./util"),
  joinModules = _require.joinModules; // must not start with a dot, as that won't go into the apk

const MAGIC_RAM_BUNDLE_FILENAME = "UNBUNDLE";
const MODULES_DIR = "js-modules";
/**
 * Saves all JS modules of an app as single files
 * The startup code (prelude, polyfills etc.) are written to the file
 * designated by the `bundleOuput` option.
 * All other modules go into a 'js-modules' folder that in the same parent
 * directory as the startup file.
 */

function saveAsAssets(bundle, options, log) {
  const bundleOutput = options.bundleOutput,
    encoding = options.bundleEncoding,
    sourcemapOutput = options.sourcemapOutput,
    sourcemapSourcesRoot = options.sourcemapSourcesRoot;
  log("start");
  const startupModules = bundle.startupModules,
    lazyModules = bundle.lazyModules;
  log("finish");
  const startupCode = joinModules(startupModules);
  log("Writing bundle output to:", bundleOutput);
  const modulesDir = path.join(path.dirname(bundleOutput), MODULES_DIR);
  const writeUnbundle = createDir(modulesDir).then(
    // create the modules directory first
    () =>
      Promise.all([
        writeModules(lazyModules, modulesDir, encoding),
        writeFile(bundleOutput, startupCode, encoding),
        writeMagicFlagFile(modulesDir)
      ])
  );
  writeUnbundle.then(() => log("Done writing unbundle output"));

  if (sourcemapOutput) {
    const sourceMap = buildSourcemapWithMetadata({
      fixWrapperOffset: true,
      lazyModules: lazyModules.concat(),
      moduleGroups: null,
      startupModules: startupModules.concat()
    });

    if (sourcemapSourcesRoot !== undefined) {
      relativizeSourceMapInline(sourceMap, sourcemapSourcesRoot);
    }

    const wroteSourceMap = writeSourceMap(
      sourcemapOutput,
      JSON.stringify(sourceMap),
      log
    );
    return Promise.all([writeUnbundle, wroteSourceMap]);
  } else {
    return writeUnbundle;
  }
}

function createDir(dirName) {
  return new Promise((resolve, reject) =>
    mkdirp(dirName, error => (error ? reject(error) : resolve()))
  );
}

function writeModuleFile(module, modulesDir, encoding) {
  const code = module.code,
    id = module.id;
  return writeFile(path.join(modulesDir, id + ".js"), code, encoding);
}

function writeModules(modules, modulesDir, encoding) {
  const writeFiles = modules.map(module =>
    writeModuleFile(module, modulesDir, encoding)
  );
  return Promise.all(writeFiles);
}

function writeMagicFlagFile(outputDir) {
  const buffer = Buffer.alloc(4);
  buffer.writeUInt32LE(MAGIC_RAM_BUNDLE_NUMBER, 0);
  return writeFile(path.join(outputDir, MAGIC_RAM_BUNDLE_FILENAME), buffer);
}

module.exports = saveAsAssets;