@obiemunoz/ts-migrate-server

ts-migrate-server is a package that contains the main migration runner.

This is a maintained fork of airbnb/ts-migrate, updated for TypeScript 5 and 6. Original work © 2020 Airbnb (MIT).

Most users should start with @obiemunoz/ts-migrate, the CLI that drives this package. Install this package directly only if you're composing a custom migration pipeline.

ts-migrate-server was originally designed around Airbnb projects. Use at your own risk.

Install

Install @obiemunoz/ts-migrate-server using npm:

npm install --save-dev @obiemunoz/ts-migrate-server

Or pnpm:

pnpm add -D @obiemunoz/ts-migrate-server

Usage

import path from 'path';
import { migrate, MigrateConfig } from '@obiemunoz/ts-migrate-server';

// get input files folder
const inputDir = path.resolve(__dirname, 'input');

// create new migration config. You can add your plugins there
const config = new MigrateConfig();

// run migration
const { exitCode } = await migrate({ rootDir: inputDir, config });

process.exit(exitCode);

FAQ

How can I use ts-migrate-server?

The basic usage example is the quickest way in. After that, the best reference is the source of the ts-migrate CLI itself, since the CLI is just a consumer of this package: it builds a MigrateConfig out of plugins and hands it to migrate.

Why a server instead of standalone codemods?

Standalone codemods each pay their own setup cost: parse the project, build a program, apply changes, repeat. The server does that once and shares it. Plugins get the parsed SourceFile and a language service backed by one shared program, updates are applied in memory between plugins, and files only hit disk at the end. That's what makes a 19-plugin pipeline practical; the plugins that need type information (like type inference against usage) would be far too slow re-creating a program per plugin per file.

Which TypeScript versions does it work with?

The peer range is >=5.0 <7, same as the rest of the fork. The compiler is a peer dependency on purpose: the program it builds should be the one your project compiles with, not whatever happened to be bundled here. Version-skew between "the compiler that parses" and "the compiler that reads the AST" is a class of bug I've been bitten by once already, and once was plenty.

I have an issue, what should I do?

Please file an issue with the smallest reproduction you can manage.

Contributing

See the Contributors Guide.