packages/babel-core/src/transform-ast.js
// @flow
import gensync from "gensync";
import loadConfig, { type InputOptions, type ResolvedConfig } from "./config";
import {
run,
type FileResult,
type FileResultCallback,
} from "./transformation";
type AstRoot = BabelNodeFile | BabelNodeProgram;
type TransformFromAst = {
(ast: AstRoot, code: string, callback: FileResultCallback): void,
(
ast: AstRoot,
code: string,
opts: ?InputOptions,
callback: FileResultCallback,
): void,
// Here for backward-compatibility. Ideally use ".transformSync" if you want
// a synchronous API.
(ast: AstRoot, code: string, opts: ?InputOptions): FileResult | null,
};
const transformFromAstRunner = gensync<
[AstRoot, string, ?InputOptions],
FileResult | null,
>(function* (ast, code, opts) {
const config: ResolvedConfig | null = yield* loadConfig(opts);
if (config === null) return null;
if (!ast) throw new Error("No AST given");
return yield* run(config, code, ast);
});
export const transformFromAst: TransformFromAst = (function transformFromAst(
ast,
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 transformFromAstRunner.sync(ast, code, opts);
}
transformFromAstRunner.errback(ast, code, opts, callback);
}: Function);
export const transformFromAstSync = transformFromAstRunner.sync;
export const transformFromAstAsync = transformFromAstRunner.async;