test(auth): Add tests for AuthService and Auth validations

frontend/src/services/auth.test.ts

@@ -0,0 +1,60 @@
+import { describe, it, expect, vi, beforeEach } from "vitest"
+import axios from "axios"
+import { AuthService } from "./auth"
+
+vi.mock("axios")
+const mockedAxios = axios as jest.Mocked<typeof axios>
+
+describe("AuthService", () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    localStorage.clear()
+  })
+
+  it("successfully logs in and stores the token", async () => {
+    const mockResponse = {
+      data: {
+        access_token: "fake-jwt-token",
+        token_type: "bearer",
+      },
+    }
+    mockedAxios.post.mockResolvedValueOnce(mockResponse)
+
+    const result = await AuthService.login("test@example.com", "password123")
+
+    expect(mockedAxios.post).toHaveBeenCalledWith("/api/auth/login", expect.any(FormData))
+    expect(result.access_token).toBe("fake-jwt-token")
+    expect(localStorage.getItem("token")).toBe("fake-jwt-token")
+  })
+
+  it("handles login failure", async () => {
+    mockedAxios.post.mockRejectedValueOnce(new Error("Invalid credentials"))
+
+    await expect(AuthService.login("test@example.com", "wrong")).rejects.toThrow("Invalid credentials")
+    expect(localStorage.getItem("token")).toBeNull()
+  })
+
+  it("successfully registers a user", async () => {
+    const mockResponse = {
+      data: {
+        id: "user-123",
+        email: "test@example.com",
+      },
+    }
+    mockedAxios.post.mockResolvedValueOnce(mockResponse)
+
+    const result = await AuthService.register("test@example.com", "password123")
+
+    expect(mockedAxios.post).toHaveBeenCalledWith("/api/auth/register", {
+      email: "test@example.com",
+      password: "password123",
+    })
+    expect(result.email).toBe("test@example.com")
+  })
+
+  it("logs out and clears the token", () => {
+    localStorage.setItem("token", "some-token")
+    AuthService.logout()
+    expect(localStorage.getItem("token")).toBeNull()
+  })
+})