Initial commit 🎉

fbshipit-source-id: b6fc29740c6875d2e78953b8a7123890a67930f2
Co-authored-by: Sebastian McKenzie <sebmck@fb.com>
Co-authored-by: John Knox <jknox@fb.com>
Co-authored-by: Emil Sjölander <emilsj@fb.com>
Co-authored-by: Pritesh Nandgaonkar <prit91@fb.com>

scripts/metro-transform.js

@@ -0,0 +1,63 @@
+/**
+ * Copyright 2018-present Facebook.
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ * @format
+ */
+
+const generate = require('babel-generator').default;
+const babylon = require('babylon');
+const babel = require('babel-core');
+const metro = require('metro');
+
+exports.transform = function({
+  filename,
+  options,
+  src,
+  plugins: defaultPlugins,
+}) {
+  const presets = [];
+
+  let ast = babylon.parse(src, {
+    filename,
+    plugins: ['jsx', 'flow', 'classProperties', 'objectRestSpread'],
+    sourceType: filename.includes('node_modules') ? 'script' : 'module',
+  });
+
+  // run babel
+  const plugins = [
+    ...defaultPlugins,
+    require('./babel-plugins/electron-requires.js'),
+    require('./babel-plugins/dynamic-requires.js'),
+  ];
+  if (!filename.includes('node_modules')) {
+    plugins.unshift(require('babel-plugin-transform-es2015-modules-commonjs'));
+  }
+  ast = babel.transformFromAst(ast, src, {
+    babelrc: !filename.includes('node_modules'),
+    code: false,
+    comments: false,
+    compact: false,
+    filename,
+    plugins,
+    presets,
+    sourceMaps: true,
+  }).ast;
+
+  const result = generate(
+    ast,
+    {
+      filename,
+      sourceFileName: filename,
+      sourceMaps: true,
+    },
+    src,
+  );
+
+  return {
+    ast,
+    code: result.code,
+    filename,
+    map: result.rawMappings.map(metro.sourceMaps.compactMapping),
+  };
+};