Add flow declarations for `babel-core`

Reviewed By: zertosh

Differential Revision: D4166844

fbshipit-source-id: 5ee67b6629179c195dcdeacf87121a3fcd75a738

flow/babel.js.flow

@@ -0,0 +1,103 @@
+/**
+ * Copyright (c) 2013-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.
+ */
+
+// based on babylon v6.13.1
+type BabylonOptions = {
+  allowImportExportEverywhere?: boolean,
+  allowReturnOutsideFunction?: boolean,
+  allowSuperOutsideMethod?: boolean,
+  sourceType?: 'script' | 'module',
+  sourceFilename?: 'string',
+  plugins?: Array<
+    'jsx' | 'flow' | 'doExpressions' | 'objectRestSpread' | 'decorators' |
+    'classProperties' | 'exportExtensions' | 'asyncGenerators' |
+    'functionBind' | 'functionSent' | 'dynamicImport'
+  >,
+};
+
+// based on babel-generator v6.18.0
+type GeneratorOptions = {
+  auxiliaryCommentBefore?: string,
+  auxiliaryCommentAfter?: string,
+  shouldPrintComment?: (comment: string) => boolean,
+  retainLines?: boolean,
+  retainFunctionParens?: boolean,
+  comments?: boolean,
+  compact?: boolean | 'auto',
+  minified?: boolean,
+  concise?: boolean,
+  quotes?: 'single' | 'double',
+  filename?: string,
+  sourceMaps?: boolean,
+  sourceMapTarget?: string,
+  sourceRoot?: string,
+  sourceFileName?: string,
+};
+
+// based on https://babeljs.io/docs/usage/options/ -- 2016-11-11
+type _TransformOptions = {
+  filename?: string,
+  filenameRelative?: string,
+  presets?: Array<string | Object>,
+  plugins?: Array<string | Object>,
+  parserOpts?: BabylonOptions,
+  generatorOpts?: GeneratorOptions,
+  highlightCode?: boolean,
+  only?: string | RegExp | Array<string | RegExp>,
+  ignore?: string | RegExp | Array<string | RegExp>,
+  auxiliaryCommentBefore?: boolean,
+  auxiliaryCommentAfter?: boolean,
+  sourceMaps?: boolean,
+  inputSourceMap?: Object,
+  sourceMapTarget?: string,
+  sourceFileName?: string,
+  sourceRoot?: string,
+  moduleRoot?: string,
+  moduleIds?: boolean,
+  moduleId?: string,
+  getModuleId?: (moduleName: string) => string,
+  resolveModuleSource?: (source: string, filename: string) => string,
+  code?: boolean,
+  babelrc?: boolean,
+  ast?: boolean,
+  compact?: boolean | 'auto',
+  minified?: boolean,
+  comments?: boolean,
+  shouldPrintComment?: (comment: string) => boolean,
+  retainLines?: boolean,
+  extends?: string,
+};
+
+type TransformOptions =
+  _TransformOptions & {env?: {[key: string]: TransformOptions}};
+type TransformResult = {};
+type VisitFn = <State>(path: Object, state: State) => any;
+
+declare module 'babel-core' {
+  declare function transform(
+    code: string,
+    options?: TransformOptions,
+  ): TransformResult;
+  declare function traverse<State>(
+    ast: Object,
+    visitor: {[key: string]: VisitFn<State> |
+                             {enter?: VisitFn<State>, exit?: VisitFn<State>}},
+    scope?: ?Object,
+    state?: State,
+    parentPath?: ?Object,
+  ): void;
+  declare var types: {[key: string]: Function};
+}
+
+declare module 'babel-generator' {
+  declare function exports(
+    ast: Object,
+    options?: GeneratorOptions,
+  ): {ast: Object, code: string, map: Object};
+}