test(dlx): cover dlx/packages package management

11 tests covering all 5 exports: isDlxPackageInstalled,
listDlxPackages, listDlxPackagesAsync, removeDlxPackage,
removeDlxPackageSync. Uses setPath() to override the cached DLX dir
to a per-test tmpdir; SOCKET_DLX_DIR env override is set as a
belt-and-suspenders. Filters out non-directory entries, handles
missing-directory paths, removes existing packages and no-ops on
missing ones.

Author: jdalton

test/unit/dlx/packages.test.mts

@@ -0,0 +1,131 @@
+/**
+ * @fileoverview Unit tests for dlx/packages — DLX package management.
+ *
+ * Uses a real tmpdir and overrides SOCKET_DLX_DIR via env so we can
+ * inspect actual filesystem state. Each test isolates with its own
+ * tmpdir.
+ */
+
+import { existsSync, mkdirSync, mkdtempSync, rmSync } from 'node:fs'
+import { tmpdir } from 'node:os'
+import path from 'node:path'
+
+import { afterEach, beforeEach, describe, expect, it } from 'vitest'
+
+import {
+  isDlxPackageInstalled,
+  listDlxPackages,
+  listDlxPackagesAsync,
+  removeDlxPackage,
+  removeDlxPackageSync,
+} from '@socketsecurity/lib/dlx/packages'
+import { setPath } from '@socketsecurity/lib/paths/rewire'
+
+let tmpDir: string
+let savedDlxDir: string | undefined
+
+describe.sequential('dlx/packages', () => {
+  beforeEach(() => {
+    tmpDir = mkdtempSync(path.join(tmpdir(), 'socket-dlx-test-'))
+    savedDlxDir = process.env['SOCKET_DLX_DIR']
+    process.env['SOCKET_DLX_DIR'] = tmpDir
+    // Override the cached path lookup so tests don't need a fresh process.
+    setPath('socket-dlx-dir', tmpDir)
+  })
+
+  afterEach(() => {
+    if (savedDlxDir === undefined) {
+      delete process.env['SOCKET_DLX_DIR']
+    } else {
+      process.env['SOCKET_DLX_DIR'] = savedDlxDir
+    }
+    setPath('socket-dlx-dir', undefined)
+    try {
+      rmSync(tmpDir, { recursive: true, force: true })
+    } catch {}
+  })
+
+  describe('isDlxPackageInstalled', () => {
+    it('returns false when the package directory does not exist', () => {
+      expect(isDlxPackageInstalled('nope')).toBe(false)
+    })
+  })
+
+  describe('listDlxPackages', () => {
+    it('returns an empty array when DLX dir is empty', () => {
+      const result = listDlxPackages()
+      expect(result).toEqual([])
+    })
+
+    it('returns sorted entries when DLX dir has subdirectories', () => {
+      const dlxRoot = tmpDir
+      mkdirSync(path.join(dlxRoot, 'zzz'), { recursive: true })
+      mkdirSync(path.join(dlxRoot, 'aaa'), { recursive: true })
+      mkdirSync(path.join(dlxRoot, 'mmm'), { recursive: true })
+      const result = listDlxPackages()
+      expect(result).toEqual(['aaa', 'mmm', 'zzz'])
+    })
+
+    it('returns empty array when DLX dir does not exist', () => {
+      // Remove the pre-created _dlx directory.
+      rmSync(tmpDir, { recursive: true, force: true })
+      const result = listDlxPackages()
+      expect(result).toEqual([])
+    })
+  })
+
+  describe('listDlxPackagesAsync', () => {
+    it('returns sorted entries when DLX dir has subdirectories', async () => {
+      const dlxRoot = tmpDir
+      mkdirSync(path.join(dlxRoot, 'beta'), { recursive: true })
+      mkdirSync(path.join(dlxRoot, 'alpha'), { recursive: true })
+      const result = await listDlxPackagesAsync()
+      expect(result).toEqual(['alpha', 'beta'])
+    })
+
+    it('filters out non-directory entries', async () => {
+      const dlxRoot = tmpDir
+      mkdirSync(path.join(dlxRoot, 'pkg-a'), { recursive: true })
+      // Drop a file (not a directory) — should be filtered out.
+      const fs = await import('node:fs')
+      fs.writeFileSync(path.join(dlxRoot, 'not-a-package.txt'), '')
+      const result = await listDlxPackagesAsync()
+      expect(result).toEqual(['pkg-a'])
+    })
+
+    it('returns empty array when DLX dir does not exist', async () => {
+      rmSync(tmpDir, { recursive: true, force: true })
+      const result = await listDlxPackagesAsync()
+      expect(result).toEqual([])
+    })
+  })
+
+  describe('removeDlxPackage', () => {
+    it('removes an existing package directory', async () => {
+      const dlxRoot = tmpDir
+      const pkgDir = path.join(dlxRoot, 'pkg-x')
+      mkdirSync(pkgDir, { recursive: true })
+      await removeDlxPackage('pkg-x')
+      expect(existsSync(pkgDir)).toBe(false)
+    })
+
+    it('does not throw when removing a non-existent package', async () => {
+      // safeDelete with force:true silently no-ops on missing paths.
+      await expect(removeDlxPackage('does-not-exist')).resolves.toBeUndefined()
+    })
+  })
+
+  describe('removeDlxPackageSync', () => {
+    it('removes an existing package directory', () => {
+      const dlxRoot = tmpDir
+      const pkgDir = path.join(dlxRoot, 'pkg-y')
+      mkdirSync(pkgDir, { recursive: true })
+      removeDlxPackageSync('pkg-y')
+      expect(existsSync(pkgDir)).toBe(false)
+    })
+
+    it('does not throw when removing a non-existent package', () => {
+      expect(() => removeDlxPackageSync('does-not-exist')).not.toThrow()
+    })
+  })
+})