unbuild migration

docs/guide/migrate-from-unbuild.md

@@ -0,0 +1,47 @@
+# Migrate from unbuild
+
+[unbuild](https://github.com/unjs/unbuild) is a popular unified JavaScript build system from the unjs ecosystem. If you're currently using `unbuild` and want to migrate to `tsdown`, the process is straightforward thanks to the dedicated `migrate` command with the `--from unbuild` option:
+
+```bash
+npx tsdown migrate --from unbuild
+```
+
+> [!WARNING]
+> Please save your changes before migration. The migration process may modify your configuration files, so it's important to ensure all your changes are committed or backed up beforehand.
+
+## What Gets Migrated
+
+The migration process handles:
+
+1. **Package.json** changes:
+   - Dependencies: Updates `unbuild` dependencies to `tsdown`
+   - Scripts: Updates any scripts using `unbuild` to use `tsdown` instead
+   - Configuration: Migrates any `unbuild` configuration in package.json to `tsdown` format
+
+2. **Config Files**:
+   - Converts `build.config.*` files to `tsdown.config.*` files
+   - Updates imports from `unbuild` to `tsdown`
+   - Transforms `defineBuildConfig` to `defineConfig`
+   - Adapts build configuration options to match tsdown equivalents
+
+## Migration Options
+
+The `migrate` command supports the following options to customize the migration process:
+
+- `--cwd <dir>` (or `-c`): Specify the working directory for the migration.
+- `--dry-run` (or `-d`): Perform a dry run to preview the migration without making any changes.
+- `--from <source>`: Specify the source bundler to migrate from (defaults to `tsup`, use `unbuild` for unbuild migration).
+
+With these options, you can easily tailor the migration process to fit your specific project setup.
+
+## Differences from unbuild
+
+While `tsdown` aims to provide a smooth migration experience from `unbuild`, there are some notable differences to be aware of:
+
+1. **Configuration Format**: tsdown uses a slightly different configuration format. The migration script handles most common options, but you may need to manually adjust some advanced configurations.
+
+2. **Builders**: unbuild's `mkdist` builder is mapped to tsdown's `dts` builder, but there might be slight differences in behavior.
+
+3. **Rollup vs Rolldown**: unbuild uses Rollup, whereas tsdown uses [Rolldown](https://rolldown.rs/), a Rust-based bundler that's faster and more efficient.
+
+After migration, it's recommended to review your configuration and build output to ensure everything is working as expected.

package.json

@@ -100,6 +100,7 @@
     "prettier": "catalog:dev",
     "publint": "catalog:dev",
     "tsup": "catalog:dev",
+    "unbuild": "catalog:prod",
     "tsx": "catalog:dev",
     "typedoc": "catalog:docs",
     "typedoc-plugin-markdown": "catalog:docs",

pnpm-workspace.yaml

@@ -44,6 +44,7 @@ catalogs:
     tinyglobby: ^0.2.13
     unconfig: ^7.3.2
     unplugin-lightningcss: ^0.3.3
+    unbuild: ^3.5.0
 
 ignoredBuiltDependencies:
   - rolldown

src/cli.ts

@@ -51,9 +51,12 @@ cli
   })
 
 cli
-  .command('migrate', 'Migrate from tsup to tsdown')
+  .command('migrate', 'Migrate from tsup or unbuild to tsdown')
   .option('-c, --cwd <dir>', 'Working directory')
   .option('-d, --dry-run', 'Dry run')
+  .option('--from <source>', 'Source bundler (tsup or unbuild)', {
+    default: 'tsup',
+  })
   .action(async (args) => {
     const { migrate } = await import('./migrate')
     await migrate(args)

src/migrate-unbuild.ts

@@ -0,0 +1,184 @@
+import { existsSync } from 'node:fs'
+import { readFile, unlink, writeFile } from 'node:fs/promises'
+import process from 'node:process'
+import consola from 'consola'
+import { version } from '../package.json'
+
+export async function migrateFromUnbuild({
+  cwd,
+  dryRun,
+}: {
+  cwd?: string
+  dryRun?: boolean
+}): Promise<void> {
+  if (dryRun) {
+    consola.info('Dry run enabled. No changes were made.')
+  } else {
+    const confirm = await consola.prompt(
+      'Please make sure to commit your changes before migrating. Continue?',
+      { type: 'confirm' },
+    )
+    if (!confirm) {
+      consola.error('Migration cancelled.')
+      process.exitCode = 1
+      return
+    }
+  }
+
+  if (cwd) process.chdir(cwd)
+
+  let migrated = await migratePackageJson(dryRun)
+  if (await migrateUnbuildConfig(dryRun)) {
+    migrated = true
+  }
+  if (migrated) {
+    consola.success(
+      'Migration completed. Remember to run install command with your package manager.',
+    )
+  } else {
+    consola.error('No migration performed.')
+    process.exitCode = 1
+  }
+}
+
+async function migratePackageJson(dryRun?: boolean): Promise<boolean> {
+  if (!existsSync('package.json')) {
+    consola.error('No package.json found')
+    return false
+  }
+
+  const pkgRaw = await readFile('package.json', 'utf-8')
+  let pkg = JSON.parse(pkgRaw)
+  const semver = `^${version}`
+  let found = false
+  if (pkg.dependencies?.unbuild) {
+    consola.info('Migrating `dependencies` to tsdown.')
+    found = true
+    pkg.dependencies = renameKey(pkg.dependencies, 'unbuild', 'tsdown', semver)
+  }
+  if (pkg.devDependencies?.unbuild) {
+    consola.info('Migrating `devDependencies` to tsdown.')
+    found = true
+    pkg.devDependencies = renameKey(
+      pkg.devDependencies,
+      'unbuild',
+      'tsdown',
+      semver,
+    )
+  }
+  if (pkg.peerDependencies?.unbuild) {
+    consola.info('Migrating `peerDependencies` to tsdown.')
+    found = true
+    pkg.peerDependencies = renameKey(
+      pkg.peerDependencies,
+      'unbuild',
+      'tsdown',
+      '*',
+    )
+  }
+  if (pkg.scripts) {
+    for (const key of Object.keys(pkg.scripts)) {
+      if (pkg.scripts[key].includes('unbuild')) {
+        consola.info(`Migrating \`${key}\` script to tsdown`)
+        found = true
+        pkg.scripts[key] = pkg.scripts[key].replaceAll(
+          /unbuild(?:-node)?/g,
+          'tsdown',
+        )
+      }
+    }
+  }
+  if (pkg.unbuild) {
+    consola.info('Migrating `unbuild` field in package.json to `tsdown`.')
+    found = true
+    pkg = renameKey(pkg, 'unbuild', 'tsdown')
+  }
+
+  if (!found) {
+    consola.warn('No unbuild-related fields found in package.json')
+    return false
+  }
+
+  const pkgStr = `${JSON.stringify(pkg, null, 2)}\n`
+  if (dryRun) {
+    const { createPatch } = await import('diff')
+    consola.info('[dry-run] package.json:')
+    console.info(createPatch('package.json', pkgRaw, pkgStr))
+  } else {
+    await writeFile('package.json', pkgStr)
+    consola.success('Migrated `package.json`')
+  }
+  return true
+}
+
+const UNBUILD_CONFIG_FILES = [
+  'build.config.ts',
+  'build.config.cts',
+  'build.config.mts',
+  'build.config.js',
+  'build.config.cjs',
+  'build.config.mjs',
+  'build.config.json',
+]
+
+async function migrateUnbuildConfig(dryRun?: boolean): Promise<boolean> {
+  let found = false
+
+  for (const file of UNBUILD_CONFIG_FILES) {
+    if (!existsSync(file)) continue
+    consola.info(`Found \`${file}\``)
+    found = true
+
+    const unbuildConfigRaw = await readFile(file, 'utf-8')
+
+    // Replace unbuild imports with tsdown
+    let tsdownConfig = unbuildConfigRaw
+      .replace(/from ["']unbuild["']/g, 'from "tsdown"')
+      .replace(/import\s*{\s*defineBuildConfig\s*}/g, 'import { defineConfig }')
+      .replace(/defineBuildConfig\(/g, 'defineConfig(')
+
+    // Replace unbuild specific options with tsdown equivalents
+    // This is a simplified approach - might need to be expanded based on actual options mapping
+    tsdownConfig = tsdownConfig
+      .replace(/builder:\s*["']mkdist["']/g, 'builder: "dts"')
+      .replace(/rollup:/g, 'rolldown:')
+
+    const tsdownFileName = file.replace('build.config', 'tsdown.config');
+
+    if (dryRun) {
+      const { createTwoFilesPatch } = await import('diff')
+      consola.info(`[dry-run] ${file} -> ${tsdownFileName}:`)
+      console.info(
+        createTwoFilesPatch(file, tsdownFileName, unbuildConfigRaw, tsdownConfig),
+      )
+    } else {
+      await writeFile(tsdownFileName, tsdownConfig, 'utf8')
+      await unlink(file)
+      consola.success(`Migrated \`${file}\` to \`${tsdownFileName}\``)
+    }
+  }
+
+  if (!found) {
+    consola.warn('No unbuild config found')
+  }
+
+  return found
+}
+
+// rename key but keep order
+function renameKey(
+  obj: Record<string, any>,
+  oldKey: string,
+  newKey: string,
+  newValue?: any,
+) {
+  const newObj: Record<string, any> = {}
+  for (const key of Object.keys(obj)) {
+    if (key === oldKey) {
+      newObj[newKey] = newValue || obj[oldKey]
+    } else {
+      newObj[key] = obj[key]
+    }
+  }
+  return newObj
+}

src/migrate.ts

@@ -3,14 +3,22 @@ import { readFile, unlink, writeFile } from 'node:fs/promises'
 import process from 'node:process'
 import consola from 'consola'
 import { version } from '../package.json'
+import { migrateFromUnbuild } from './migrate-unbuild'
 
 export async function migrate({
   cwd,
   dryRun,
+  from,
 }: {
   cwd?: string
   dryRun?: boolean
+  from?: 'tsup' | 'unbuild'
 }): Promise<void> {
+  if (from === 'unbuild') {
+    return migrateFromUnbuild({ cwd, dryRun })
+  }
+
+  // Default to tsup migration
   if (dryRun) {
     consola.info('Dry run enabled. No changes were made.')
   } else {