tests: add cache key unit tests

projects/nx-verdaccio/src/plugin/caching.unit-test.ts

@@ -0,0 +1,59 @@
+import { afterEach, describe, expect, type MockInstance } from 'vitest';
+import { cacheKey } from './caching';
+import * as fileHasher from 'nx/src/hasher/file-hasher';
+
+
+describe('cacheKey', (): void => {
+  const prefix = 'warcraft';
+  const hashData = { race: 'orc' };
+  let hashObjectSpy: MockInstance<[obj: object], string>;
+
+  describe('hashed object', (): void => {
+    beforeEach((): void => {
+      hashObjectSpy = vi.spyOn(fileHasher, 'hashObject');
+    });
+    afterEach((): void => {
+      hashObjectSpy.mockRestore();
+    });
+    it('should return cache key with hashed object when it is empty', (): void => {
+      // {} = 3244421341483603138
+      expect(cacheKey(prefix, {})).toBe(`${prefix}-3244421341483603138`);
+    });
+    it('should return cache key with hashed object when it is NOT empty', (): void => {
+      // { race: 'orc' } = 9075797468634534731
+      expect(cacheKey(prefix, hashData)).toBe(`${prefix}-5048043832971198124`);
+    });
+    it('should call hashObject with the correct data', () => {
+      const hashObjectSpy = vi.spyOn(fileHasher, 'hashObject');
+
+      const result = cacheKey(prefix, hashData);
+
+      expect(hashObjectSpy).toHaveBeenCalledTimes(1);
+      expect(hashObjectSpy).toHaveBeenCalledWith(hashData);
+      expect(result).toContain(prefix);
+    });
+    it('should return unmodified hashObject return value', (): void => {
+      const hashObjectSpy = vi
+        .spyOn(fileHasher, 'hashObject')
+        .mockImplementation((): string => 'mocked-hash');
+      const result = cacheKey(prefix, hashData);
+
+      expect(result).toBe(`${prefix}-mocked-hash`);
+      expect(hashObjectSpy).toHaveBeenCalledTimes(1);
+      expect(hashObjectSpy).toHaveBeenCalledWith(hashData);
+    });
+  });
+  describe('prefix', (): void => {
+    it('should return cache key with unmodified prefix', (): void => {
+      // {} = 3244421341483603138
+      expect(cacheKey(prefix, {})).toBe(`${prefix}-3244421341483603138`);
+    });
+  });
+  describe('format', (): void => {
+    const regex = /^[a-zA-Z]+-\d+$/;
+    it('should return a value in the format "string-numbers"', (): void => {
+      const result = cacheKey(prefix, hashData);
+      expect(result).toMatch(regex);
+    });
+  });
+});