add test

Author: Lms24

test/utils/package-manager.test.ts

@@ -0,0 +1,36 @@
+import {
+  detectPackageManger,
+  NPM,
+  PNPM,
+  YARN_V1,
+} from '../../src/utils/package-manager';
+
+describe('detectPackageManager', () => {
+  it('returns the detected package manager if exactly one is found', () => {
+    const pnpm = { ...PNPM, detect: () => true };
+
+    const packageManager = detectPackageManger([
+      { ...NPM, detect: () => false },
+      { ...YARN_V1, detect: () => false },
+      pnpm,
+    ]);
+
+    expect(packageManager).toBe(pnpm);
+  });
+
+  it('returns null if no package manager is found', () => {
+    const packageManager = detectPackageManger([
+      { ...NPM, detect: () => false },
+      { ...YARN_V1, detect: () => false },
+    ]);
+    expect(packageManager).toBeNull();
+  });
+
+  it('returns null if multiple package managers are found', () => {
+    const packageManager = detectPackageManger([
+      { ...NPM, detect: () => true },
+      { ...YARN_V1, detect: () => true },
+    ]);
+    expect(packageManager).toBeNull();
+  });
+});