packages/babel-core/src/transform.js
// @flow
import gensync from "gensync";
import loadConfig, { type InputOptions, type ResolvedConfig } from "./config";
import {
run,
type FileResult,
type FileResultCallback,
} from "./transformation";
type Transform = {
(code: string, callback: FileResultCallback): void,
(code: string, opts: ?InputOptions, callback: FileResultCallback): void,
// Here for backward-compatibility. Ideally use ".transformSync" if you want
// a synchronous API.
(code: string, opts: ?InputOptions): FileResult | null,
};
const transformRunner = gensync<[string, ?InputOptions], FileResult | null>(
function* transform(code, opts) {
const config: ResolvedConfig | null = yield* loadConfig(opts);
if (config === null) return null;
return yield* run(config, code);
},
);
export const transform: Transform = (function transform(code, opts, callback) {
if (typeof opts === "function") {
callback = opts;
opts = undefined;
}
// For backward-compat with Babel 6, we allow sync transformation when
// no callback is given. Will be dropped in some future Babel major version.
if (callback === undefined) return transformRunner.sync(code, opts);
transformRunner.errback(code, opts, callback);
}: Function);
export const transformSync = transformRunner.sync;
export const transformAsync = transformRunner.async;