feat: add stop option to detect

src/detect.ts

@@ -11,7 +11,7 @@ import { AGENTS, LOCKS } from './constants'
  * @returns {Promise<DetectResult | null>} The detected package manager or `null` if not found.
  */
 export async function detect(options: DetectOptions = {}): Promise<DetectResult | null> {
-  const { cwd, onUnknown } = options
+  const { cwd, onUnknown, stop } = options
 
   for (const directory of lookup(cwd)) {
     // Look up for lock files
@@ -29,6 +29,10 @@ export async function detect(options: DetectOptions = {}): Promise<DetectResult
     const result = await parsePackageJson(path.join(directory, 'package.json'), onUnknown)
     if (result)
       return result
+
+    // Stop the traversing if the stop directory is reached
+    if (stop && path.resolve(directory) === path.resolve(stop))
+      break
   }
 
   return null
@@ -40,7 +44,7 @@ export async function detect(options: DetectOptions = {}): Promise<DetectResult
  * @returns {DetectResult | null>} The detected package manager or `null` if not found.
  */
 export function detectSync(options: DetectOptions = {}): DetectResult | null {
-  const { cwd, onUnknown } = options
+  const { cwd, onUnknown, stop } = options
 
   for (const directory of lookup(cwd)) {
     // Look up for lock files
@@ -58,6 +62,10 @@ export function detectSync(options: DetectOptions = {}): DetectResult | null {
     const result = parsePackageJsonSync(path.join(directory, 'package.json'), onUnknown)
     if (result)
       return result
+
+    // Stop the traversing if the stop directory is reached
+    if (stop && path.resolve(directory) === path.resolve(stop))
+      break
   }
 
   return null

src/types.ts

@@ -42,6 +42,10 @@ export interface DetectOptions {
    * @param packageManager - The `packageManager` value from package.json file.
    */
   onUnknown?: (packageManager: string) => DetectResult | null | undefined
+  /**
+   * The path to stop traversing up the directory.
+   */
+  stop?: string
 }
 
 export interface DetectResult {

test/detect-sync.spec.ts

@@ -42,3 +42,35 @@ fixtures.forEach(fixture => describe(fixture, () => agents.forEach((agent) => {
     expect(infoLog).not.toHaveBeenCalled()
   })
 })))
+
+it('stops at specified directory', async () => {
+  const cwd = await fs.mkdtemp(path.join(tmpdir(), 'ni-'))
+
+  const noFilesDir = path.join(cwd, 'no-files')
+  const nestedNoFilesDir = path.join(noFilesDir, 'nested')
+  const parentDir = cwd
+
+  await fs.mkdirp(noFilesDir)
+  await fs.mkdirp(nestedNoFilesDir)
+
+  await fs.copy(
+    path.join(__dirname, 'fixtures', 'lockfile', 'npm'),
+    parentDir,
+  )
+
+  const resultWithStop = detectSync({
+    cwd: nestedNoFilesDir,
+    stop: noFilesDir,
+  })
+
+  expect(resultWithStop).toBe(null)
+
+  const resultWithoutStop = detectSync({
+    cwd: nestedNoFilesDir,
+  })
+
+  expect(resultWithoutStop).toMatchObject({
+    name: 'npm',
+    agent: 'npm',
+  })
+})

test/detect.spec.ts

@@ -42,3 +42,35 @@ fixtures.forEach(fixture => describe(fixture, () => agents.forEach((agent) => {
     expect(infoLog).not.toHaveBeenCalled()
   })
 })))
+
+it('stops at specified directory', async () => {
+  const cwd = await fs.mkdtemp(path.join(tmpdir(), 'ni-'))
+
+  const noFilesDir = path.join(cwd, 'no-files')
+  const nestedNoFilesDir = path.join(noFilesDir, 'nested')
+  const parentDir = cwd
+
+  await fs.mkdirp(noFilesDir)
+  await fs.mkdirp(nestedNoFilesDir)
+
+  await fs.copy(
+    path.join(__dirname, 'fixtures', 'lockfile', 'npm'),
+    parentDir,
+  )
+
+  const resultWithStop = await detect({
+    cwd: nestedNoFilesDir,
+    stop: noFilesDir,
+  })
+
+  expect(resultWithStop).toBe(null)
+
+  const resultWithoutStop = await detect({
+    cwd: nestedNoFilesDir,
+  })
+
+  expect(resultWithoutStop).toMatchObject({
+    name: 'npm',
+    agent: 'npm',
+  })
+})