test: add performance test for code in GitHub stats fetcher file

Author: FajarKim

tests/renderStatsCard.test.ts

@@ -34,6 +34,7 @@ const exampleUserData: User = {
   totalCommitContributions: 1200,
   restrictedContributionsCount: 130,
   totalPullRequestReviewContributions: 340,
+  joinedAt: "2020-01-01T00:00:00Z",
 };
 
 describe("Test GitHub Readme Profile API", () => {
@@ -68,6 +69,17 @@ describe("Test GitHub Readme Profile API", () => {
     expect(mockResponse.setHeader).toHaveBeenCalledWith("Cache-Control", "s-maxage=7200, stale-while-revalidate");
   });
 
+  it("should return an error response when GitHub API fails", async () => {
+    mockRequest.query.username = "FajarKim";
+    mockRequest.query.format = "json";
+    (getData as jest.Mock).mockRejectedValueOnce(new Error("GitHub API error"));
+
+    await readmeStats(mockRequest, mockResponse);
+
+    expect(mockResponse.status).toHaveBeenCalledWith(500);
+    expect(mockResponse.send).toHaveBeenCalledWith("Error fetching data from GitHub API");
+  });
+
   it("should handle request and generate SVG response", async () => {
     mockRequest.query.username = "FajarKim";
     mockRequest.query.format = "svg";
@@ -148,4 +160,81 @@ describe("Test GitHub Readme Profile API", () => {
     expect(mockResponse.send).toHaveBeenCalled();
     expect(mockResponse.json).not.toHaveBeenCalled();
   });
+
+  it("should validate User data conforms to interface", async () => {
+    mockRequest.query.username = "FajarKim";
+    (getData as jest.Mock).mockResolvedValueOnce(exampleUserData);
+
+    await readmeStats(mockRequest, mockResponse);
+
+    const userData = mockResponse.json.mock.calls[0][0];
+    expect(userData).toHaveProperty("name");
+    expect(userData).toHaveProperty("login");
+    expect(userData).toHaveProperty("avatarUrl");
+    expect(userData.repositories.totalCount).toBeGreaterThanOrEqual(0);
+  });
+
+  it("should handle user with zero contributions", async () => {
+    const zeroContributionsData = {
+      ...exampleUserData,
+      totalCommitContributions: 0,
+      restrictedContributionsCount: 0,
+      totalPullRequestReviewContributions: 0,
+    };
+
+    (getData as jest.Mock).mockResolvedValueOnce(zeroContributionsData);
+
+    mockRequest.query.username = "FajarKim";
+
+    await readmeStats(mockRequest, mockResponse);
+
+    expect(mockResponse.json).toHaveBeenCalledWith(zeroContributionsData);
+  });
+
+  it("should handle very large contribution data without errors", async () => {
+    const highContributionsData = {
+      ...exampleUserData,
+      totalCommitContributions: 100000,
+      restrictedContributionsCount: 50000,
+      totalPullRequestReviewContributions: 30000,
+    };
+
+    (getData as jest.Mock).mockResolvedValueOnce(highContributionsData);
+
+    mockRequest.query.username = "FajarKim";
+
+    await readmeStats(mockRequest, mockResponse);
+
+    expect(mockResponse.json).toHaveBeenCalledWith(highContributionsData);
+  });
+
+  it("should fetch the user's join date and calculate total commits from join date until now", async () => {
+    mockRequest.query.username = "FajarKim";
+    (getData as jest.Mock).mockResolvedValueOnce(exampleUserData);
+
+    const today = new Date("2023-10-26"); 
+    const joinDate = new Date(exampleUserData.joinedAt);
+    const totalDaysSinceJoining = Math.floor((today.getTime() - joinDate.getTime()) / (1000 * 60 * 60 * 24));
+
+    await readmeStats(mockRequest, mockResponse);
+
+    const responseData = mockResponse.json.mock.calls[0][0];
+    expect(responseData.joinedAt).toEqual(exampleUserData.joinedAt);
+
+    const expectedTotalCommits = exampleUserData.totalCommitContributions + totalDaysSinceJoining;
+    expect(responseData.totalCommitContributionsSinceJoining).toEqual(expectedTotalCommits);
+  });
+
+  it("should handle missing join date gracefully", async () => {
+    const incompleteUserData = { ...exampleUserData, joinedAt: undefined };
+    (getData as jest.Mock).mockResolvedValueOnce(incompleteUserData);
+
+    mockRequest.query.username = "FajarKim";
+
+    await readmeStats(mockRequest, mockResponse);
+
+    const responseData = mockResponse.json.mock.calls[0][0];
+    expect(responseData.joinedAt).toBeUndefined();
+    expect(responseData.totalCommitContributionsSinceJoining).toBeUndefined();
+  });
 });