feat: add resolveLockfile (#14)

Co-authored-by: Pooya Parsa <pooya@pi0.io>

README.md

@@ -97,6 +97,15 @@ const filename = await resolveFile('README.md', {
 })
 ```
 
+### `resolveLockFile`
+
+Find path to the lock file (`yarn.lock`, `package-lock.json`, `pnpm-lock.yaml`, `npm-shrinkwrap.json`) or throws an error.
+
+```js
+import { resolveLockFile } from 'pkg-types'
+const lockfile = await resolveFile('.')
+```
+
 ## Types
 
 **Note:** In order to make types working, you need to install `typescript` as a devDependency.

src/index.ts

@@ -47,3 +47,16 @@ export async function resolveTSConfig (id: string = process.cwd(), opts: Resolve
   const resolvedPath = isAbsolute(id) ? id : await resolvePath(id, opts)
   return findNearestFile('tsconfig.json', { startingFrom: resolvedPath, ...opts })
 }
+
+const lockFiles = ['yarn.lock', 'package-lock.json', 'pnpm-lock.yaml', 'npm-shrinkwrap.json']
+
+export async function resolveLockfile (id: string = process.cwd(), opts: ResolveOptions = {}): Promise<string> {
+  const resolvedPath = isAbsolute(id) ? id : await resolvePath(id, opts)
+  const _opts = { startingFrom: resolvedPath, ...opts }
+  for (const lockFile of lockFiles) {
+    try {
+      return await findNearestFile(lockFile, _opts)
+    } catch { }
+  }
+  throw new Error('No lockfile found from ' + id)
+}

test/index.test.ts

@@ -10,7 +10,8 @@ import {
   writePackageJSON,
   writeTSConfig,
   TSConfig,
-  ResolveOptions
+  ResolveOptions,
+  resolveLockfile
 } from '../src'
 
 const fixtureDir = resolve(dirname(fileURLToPath(import.meta.url)), 'fixture')
@@ -87,3 +88,12 @@ describe('tsconfig.json', () => {
     // expectTypeOf(options.maxNodeModuleJsDepth).toEqualTypeOf<number | undefined>()
   })
 })
+
+describe('resolveLockfile', () => {
+  it('works for subdir', async () => {
+    expect(await resolveLockfile(rFixture('./sub'))).to.equal(rFixture('./sub/yarn.lock'))
+  })
+  it('works for root dir', async () => {
+    expect(await resolveLockfile(rFixture('.'))).to.equal(rFixture('../..', 'pnpm-lock.yaml'))
+  })
+})