Upgrade Prepack to Babel 7 (#2256)

Summary:
Release notes: upgrades Prepack to use Babel 7.0.0-beta.53

This is a big PR that updates all of Prepack to Babel 7. Babylon is now `babel/parser` and pretty much all of the the previous Babel packages are now located in scoped packages. I had to make a bunch of changes around Jest/Flow/Webpack to get this all working. The build times of building Prepack itself seem considerably faster (easily twice as fast locally). I followed most of the Babel 6 -> 7 upgrade guide from the Babel site in terms of changing nodes and type definitions to match the new ones.
Pull Request resolved: #2256

Differential Revision: D8850583

Pulled By: trueadm

fbshipit-source-id: 2d2aaec25c6a1ccd1ec0c08c5e7e2a71f78ac2d8

.circleci/config.yml

@@ -60,7 +60,7 @@ jobs:
             yarn test-sourcemaps
             yarn test-std-in
             yarn test-residual
-            yarn test-test262 --expectedCounts 11945,5566,0 --statusFile ~/artifacts/test262-status.txt --timeout 120 --cpuScale 0.25 --verbose
+            yarn test-test262 --expectedCounts 11944,5566,0 --statusFile ~/artifacts/test262-status.txt --timeout 120 --cpuScale 0.25 --verbose
             #yarn test-test262-new --statusFile ~/artifacts/test262-new-status.txt --timeout 120 --verbose
       - store_artifacts:
           path: ~/artifacts/

.eslintignore

@@ -4,3 +4,4 @@ lib
 underscore-with-tests.js
 flow-typed
 test/**/*.js
+babel.config.js

.flowconfig

@@ -1,5 +1,5 @@
 [ignore]
-.*/node_modules/babel.*
+.*/node_modules/@babel/.*
 .*/test262/.*
 .*/node_modules/.*\.json
 .*/lib/.*
@@ -8,6 +8,7 @@
 .*/test/serializer/.*
 .*/scripts/prettier.js
 .*/tmp_website_build/.*
+babel.config.js
 
 [include]
 

babel.config.js

@@ -0,0 +1,50 @@
+/**
+ * Copyright (c) 2017-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+module.exports = function (api) {
+  api.cache(true);
+
+  const plugins = [
+    "@babel/plugin-syntax-flow",
+    "@babel/plugin-syntax-jsx",
+    "@babel/plugin-transform-flow-strip-types",
+    "@babel/plugin-transform-react-jsx",
+    "@babel/plugin-transform-react-display-name",
+    "@babel/plugin-proposal-class-properties",
+    "@babel/plugin-proposal-object-rest-spread",
+  ];
+
+  // Webpack bundle
+  if (process.env.NODE_ENV === "production") {
+    return {
+      presets: [
+        ["@babel/env", {
+          "targets": {
+            "ie": "10",
+          },
+          forceAllTransforms: true,
+        }],
+        "@babel/preset-flow",
+      ],
+      plugins,
+    };
+  }
+  // Default
+  return {
+    presets: [
+      ["@babel/env", {
+        "targets": {
+          "node": "6.10",
+        }
+      }],
+      "@babel/preset-flow",
+    ],
+    plugins,
+  };
+};

flow-typed/npm/@babel/cli_vx.x.x.js

@@ -0,0 +1,87 @@
+// flow-typed signature: 88e150a250102d8b47b86c4a28175644
+// flow-typed version: <<STUB>>/@babel/cli_v^7.0.0-beta.53/flow_v0.76.0
+
+/**
+ * This is an autogenerated libdef stub for:
+ *
+ *   '@babel/cli'
+ *
+ * Fill this stub out by replacing all the `any` types.
+ *
+ * Once filled out, we encourage you to share your work with the
+ * community by sending a pull request to:
+ * https://github.com/flowtype/flow-typed
+ */
+
+declare module '@babel/cli' {
+  declare module.exports: any;
+}
+
+/**
+ * We include stubs for each file inside this npm package in case you need to
+ * require those files directly. Feel free to delete any files that aren't
+ * needed.
+ */
+declare module '@babel/cli/bin/babel-external-helpers' {
+  declare module.exports: any;
+}
+
+declare module '@babel/cli/bin/babel' {
+  declare module.exports: any;
+}
+
+declare module '@babel/cli/lib/babel-external-helpers' {
+  declare module.exports: any;
+}
+
+declare module '@babel/cli/lib/babel/dir' {
+  declare module.exports: any;
+}
+
+declare module '@babel/cli/lib/babel/file' {
+  declare module.exports: any;
+}
+
+declare module '@babel/cli/lib/babel/index' {
+  declare module.exports: any;
+}
+
+declare module '@babel/cli/lib/babel/options' {
+  declare module.exports: any;
+}
+
+declare module '@babel/cli/lib/babel/util' {
+  declare module.exports: any;
+}
+
+// Filename aliases
+declare module '@babel/cli/bin/babel-external-helpers.js' {
+  declare module.exports: $Exports<'@babel/cli/bin/babel-external-helpers'>;
+}
+declare module '@babel/cli/bin/babel.js' {
+  declare module.exports: $Exports<'@babel/cli/bin/babel'>;
+}
+declare module '@babel/cli/index' {
+  declare module.exports: $Exports<'@babel/cli'>;
+}
+declare module '@babel/cli/index.js' {
+  declare module.exports: $Exports<'@babel/cli'>;
+}
+declare module '@babel/cli/lib/babel-external-helpers.js' {
+  declare module.exports: $Exports<'@babel/cli/lib/babel-external-helpers'>;
+}
+declare module '@babel/cli/lib/babel/dir.js' {
+  declare module.exports: $Exports<'@babel/cli/lib/babel/dir'>;
+}
+declare module '@babel/cli/lib/babel/file.js' {
+  declare module.exports: $Exports<'@babel/cli/lib/babel/file'>;
+}
+declare module '@babel/cli/lib/babel/index.js' {
+  declare module.exports: $Exports<'@babel/cli/lib/babel/index'>;
+}
+declare module '@babel/cli/lib/babel/options.js' {
+  declare module.exports: $Exports<'@babel/cli/lib/babel/options'>;
+}
+declare module '@babel/cli/lib/babel/util.js' {
+  declare module.exports: $Exports<'@babel/cli/lib/babel/util'>;
+}