babel/packages/babel-core/src/transform-file.js

43 lines
1.0 KiB
JavaScript

// @flow
import fs from "fs";
import loadConfig, { type InputOptions } from "./config";
import { runAsync, type FileResultCallback } from "./transformation";
type TransformFile = {
(filename: string, callback: FileResultCallback): void,
(filename: string, opts: ?InputOptions, callback: FileResultCallback): void,
};
export default ((function transformFile(filename, opts, callback) {
if (typeof opts === "function") {
callback = opts;
opts = undefined;
}
if (opts == null) {
opts = { filename };
} else if (opts && typeof opts === "object") {
opts = Object.assign(opts, { filename });
}
process.nextTick(() => {
let cfg;
try {
cfg = loadConfig(opts);
if (cfg === null) return callback(null, null);
} catch (err) {
return callback(err);
}
// Reassignment to keep Flow happy.
const config = cfg;
fs.readFile(filename, "utf8", function(err, code: string) {
if (err) return callback(err, null);
runAsync(config, code, null, callback);
});
});
}: Function): TransformFile);