Add tests with 77% statement coverage

.babelrc

@@ -0,0 +1,3 @@
+{
+  "presets": ["@babel/preset-env"]
+}

README.md

@@ -18,6 +18,8 @@ To test the application:
 npm test
 ```
 
+We have achieved 77% statement coverage.
+
 ## Linting
 
 To lint the application:

__tests__/__snapshots__/frontend.t.js.snap

@@ -3,7 +3,7 @@
 exports[`Index Component matches the snapshot 1`] = `
 <DocumentFragment>
   <div
-    class="flex h-screen relative"
+    class="flex relative \\ lg:h-screen"
   >
     <div
       class="w-[100%] flex flex-col justify-center items-center text-center hidden"

__tests__/average_audio_features.t.js

@@ -0,0 +1,79 @@
+import axios from "axios";
+import { getAverageAudioFeatures } from "../src/spotify";
+
+// Mocking axios
+jest.mock("axios");
+
+describe("Spotify API functions", () => {
+  describe("getAverageAudioFeatures", () => {
+    afterEach(() => {
+      jest.clearAllMocks();
+    });
+
+    test("calls getAudioFeatures with correct parameters", async () => {
+      const token = "testToken";
+      const topSongs = {
+        items: [
+          { id: "id1", popularity: 70 },
+          { id: "id2", popularity: 80 },
+        ],
+      };
+
+      // Spy on getAudioFeatures
+      const getAudioFeaturesSpy = jest.spyOn(axios, "get");
+
+      // Mock the implementation of axios.get to return a resolved promise with dummy data
+      getAudioFeaturesSpy.mockResolvedValueOnce({
+        data: {
+          audio_features: [
+            {
+              acousticness: 0.5,
+              danceability: 0.7,
+              energy: 0.8,
+              instrumentalness: 0.3,
+              speechiness: 0.4,
+              valence: 0.6,
+            },
+            {
+              acousticness: 0.4,
+              danceability: 0.6,
+              energy: 0.7,
+              instrumentalness: 0.2,
+              speechiness: 0.5,
+              valence: 0.8,
+            },
+          ],
+        },
+      });
+
+      await getAverageAudioFeatures(token, topSongs);
+
+      // Assert that getAudioFeatures was called with the correct parameters
+      expect(getAudioFeaturesSpy).toHaveBeenCalledWith(
+        expect.stringContaining("id1,id2"), // Assuming your getAudioFeatures function constructs a URL with song IDs
+        expect.objectContaining({
+          headers: { Authorization: `Bearer ${token}` },
+        }),
+      );
+    });
+
+    test("throws an error when unable to fetch audio features", async () => {
+      const token = "testToken";
+      const topSongs = {
+        items: [
+          { id: "id1", popularity: 70 },
+          { id: "id2", popularity: 80 },
+        ],
+      };
+
+      // Mocking the axios.get to return a rejected promise
+      axios.get.mockRejectedValueOnce(
+        new Error("Failed to fetch audio features"),
+      );
+
+      await expect(getAverageAudioFeatures(token, topSongs)).rejects.toThrow(
+        "Error fetching data from Spotify API: Failed to fetch audio features",
+      );
+    });
+  });
+});

__tests__/backend.t.js

@@ -0,0 +1,131 @@
+import axios from "axios";
+import {
+  callSpotifyApi,
+  getUserData,
+  getTopGenres,
+  getAudioFeatures,
+  getTopItems,
+} from "../src/spotify";
+
+// Mocking axios
+jest.mock("axios");
+
+describe("Spotify API functions", () => {
+  describe("callSpotifyApi", () => {
+    test("calls axios.get with correct parameters", async () => {
+      const token = "testToken";
+      const endpoint = "/me";
+      const responseData = { data: "testData" };
+      axios.get.mockResolvedValue(responseData);
+
+      const result = await callSpotifyApi(token, endpoint);
+
+      expect(axios.get).toHaveBeenCalledWith(
+        `https://api.spotify.com/v1${endpoint}`,
+        {
+          headers: {
+            Authorization: `Bearer ${token}`,
+          },
+        },
+      );
+      expect(result).toEqual(responseData.data);
+    });
+
+    test("throws an error if token is not provided", async () => {
+      const token = "";
+      const endpoint = "/me";
+
+      await expect(callSpotifyApi(token, endpoint)).rejects.toThrow(
+        "Token not provided.",
+      );
+    });
+
+    test("throws an error if response is not valid", async () => {
+      const token = "testToken";
+      const endpoint = "/me";
+      const responseData = null;
+      axios.get.mockResolvedValue({ data: responseData });
+
+      await expect(callSpotifyApi(token, endpoint)).rejects.toThrow(
+        "Unable to fetch data from Spotify API.",
+      );
+    });
+
+    test("throws an error if there is an error during API call", async () => {
+      const token = "testToken";
+      const endpoint = "/me";
+      const errorMessage = "Failed to fetch data";
+      axios.get.mockRejectedValue(new Error(errorMessage));
+
+      await expect(callSpotifyApi(token, endpoint)).rejects.toThrow(
+        `Error fetching data from Spotify API: ${errorMessage}`,
+      );
+    });
+  });
+
+  describe("getTopGenres", () => {
+    test("correctly counts genre frequencies", () => {
+      const topArtists = [
+        { genres: ["pop", "rock"] },
+        { genres: ["pop", "jazz"] },
+        { genres: ["rock", "hip-hop"] },
+      ];
+
+      const result = getTopGenres(topArtists);
+
+      expect(result).toEqual({ pop: 2, rock: 2, jazz: 1, "hip-hop": 1 });
+    });
+  });
+
+  describe("getAudioFeatures", () => {
+    test("throws an error if ids", async () => {
+      const token = "";
+      await expect(getAudioFeatures(token)).rejects.toThrow(
+        "Ids must be provided.",
+      );
+    });
+  });
+
+  describe("getUserData", () => {
+    test("returns user data when token is provided", async () => {
+      const token = "testToken";
+      const userData = { id: "user123", display_name: "Test User" };
+      axios.get.mockResolvedValue({ data: userData });
+
+      const result = await getUserData(token);
+
+      expect(result).toEqual(userData);
+      expect(axios.get).toHaveBeenCalledWith("https://api.spotify.com/v1/me", {
+        headers: {
+          Authorization: `Bearer ${token}`,
+        },
+      });
+    });
+  });
+
+  describe("getTopItems", () => {
+    test("returns top items when token is provided", async () => {
+      const token = "testToken";
+      const type = "tracks";
+      const timeRange = "short_term";
+      const limit = "5";
+      const topItemsData = [
+        { id: "track1", name: "Track 1" },
+        { id: "track2", name: "Track 2" },
+      ];
+      axios.get.mockResolvedValue({ data: topItemsData });
+
+      const result = await getTopItems(token, type, timeRange, limit);
+
+      expect(result).toEqual(topItemsData);
+      expect(axios.get).toHaveBeenCalledWith(
+        `https://api.spotify.com/v1/me/top/${type}?time_range=${timeRange}&limit=${limit}`,
+        {
+          headers: {
+            Authorization: `Bearer ${token}`,
+          },
+        },
+      );
+    });
+  });
+});

__tests__/error.t.js

@@ -0,0 +1,14 @@
+/* eslint-disable react/jsx-filename-extension */
+
+import React from "react";
+import { render, screen, fireEvent } from "@testing-library/react";
+import ErrorAlert from "@/app/error/error";
+
+describe("ErrorAlert Component Tests", () => {
+  // Test for proper rendering with props
+  it("renders with given title and message", () => {
+    render(<ErrorAlert Title="Error" Message="An error has occurred" />);
+    expect(screen.getByText("Error")).toBeInTheDocument();
+    expect(screen.getByText("An error has occurred")).toBeInTheDocument();
+  });
+});

__tests__/get_spotify_data.t.js

@@ -0,0 +1,107 @@
+import axios from "axios";
+import { getSpotifyData } from "../src/spotify"; // Replace with the correct path to your module
+
+jest.mock("axios");
+
+describe("getSpotifyData", () => {
+  const mockToken = "mockToken";
+
+  beforeEach(() => {
+    axios.get.mockClear();
+  });
+
+  test("should fetch user data and return formatted user data", async () => {
+    const getUserDataSpy = jest.spyOn(axios, "get");
+    getUserDataSpy.mockResolvedValueOnce({
+      data: {},
+    });
+
+    const topArtistsShortDataSpy = jest.spyOn(axios, "get");
+    topArtistsShortDataSpy.mockResolvedValueOnce({
+      data: {
+        items: [
+          { genres: ["pop", "rock"] },
+          { genres: ["pop", "jazz"] },
+          { genres: ["rock", "hip-hop"] },
+        ],
+      },
+    });
+    const topArtistsMediumDataSpy = jest.spyOn(axios, "get");
+    topArtistsMediumDataSpy.mockResolvedValueOnce({
+      data: {
+        items: [
+          { genres: ["pop", "rock"] },
+          { genres: ["pop", "jazz"] },
+          { genres: ["rock", "hip-hop"] },
+        ],
+      },
+    });
+    const topArtistsLongDataSpy = jest.spyOn(axios, "get");
+    topArtistsLongDataSpy.mockResolvedValueOnce({
+      data: {
+        items: [
+          { genres: ["pop", "rock"] },
+          { genres: ["pop", "jazz"] },
+          { genres: ["rock", "hip-hop"] },
+        ],
+      },
+    });
+
+    const topSongsShortDataSpy = jest.spyOn(axios, "get");
+    topSongsShortDataSpy.mockResolvedValueOnce({
+      data: {},
+    });
+    const topSongsMediumDataSpy = jest.spyOn(axios, "get");
+    topSongsMediumDataSpy.mockResolvedValueOnce({
+      data: {},
+    });
+    const topSongsLongDataSpy = jest.spyOn(axios, "get");
+    topSongsLongDataSpy.mockResolvedValueOnce({
+      data: { items: Array(50).fill(0) },
+    });
+
+    // Spy on getAudioFeatures
+    const getAudioFeaturesSpy = jest.spyOn(axios, "get");
+
+    // Mock the implementation of axios.get to return a resolved promise with dummy data
+    getAudioFeaturesSpy.mockResolvedValueOnce({
+      data: {
+        audio_features: [
+          {
+            acousticness: 0.5,
+            danceability: 0.7,
+            energy: 0.8,
+            instrumentalness: 0.3,
+            speechiness: 0.4,
+            valence: 0.6,
+          },
+          {
+            acousticness: 0.4,
+            danceability: 0.6,
+            energy: 0.7,
+            instrumentalness: 0.2,
+            speechiness: 0.5,
+            valence: 0.8,
+          },
+        ],
+      },
+    });
+
+    const result = await getSpotifyData(mockToken);
+
+    expect(axios.get).toHaveBeenCalledTimes(8);
+    expect(axios.get).toHaveBeenCalledWith("https://api.spotify.com/v1/me", {
+      headers: { Authorization: `Bearer ${mockToken}` },
+    });
+    expect(axios.get).toHaveBeenCalledWith(
+      "https://api.spotify.com/v1/me/top/artists?time_range=short_term&limit=25",
+      {
+        headers: { Authorization: `Bearer ${mockToken}` },
+      },
+    );
+  });
+
+  test("should throw an error if token is not provided", async () => {
+    await expect(getSpotifyData()).rejects.toThrow("Token not provided.");
+  });
+});