test: write tests for refreshHuggingfaceAccessToken method

Create `refreshHuggingfaceAccessToken.test.ts` file and write in
it two integration tests for `refreshHuggingfaceAccessToken` service
method of `HuggingfaceService` class.

src/constants/operationsResultsMessages.ts

@@ -48,6 +48,7 @@ const operationsResultsMessages = {
   noLinkedDatasetRepository: "The dataset has no linked huggingface repository",
   successfulDatasetSyncWithRepository:
     "The Dataset has been synced with the repository successfully",
+  failedAccessTokenRefreshing: "Failed to refresh user's Huggingface access token"
 };
 
 export default operationsResultsMessages;

src/services/huggingface/refreshHuggingfaceAccessToken_service.ts

@@ -1,6 +1,7 @@
 import DatasetsModel from "../../models/DatasetsModel";
 import ServiceOperationResult from "../../utilities/ServiceOperationResult";
 import { refreshAccessToken } from "./huggingFaceOAuthTokenRequests";
+import operationsResultsMessages from "../../constants/operationsResultsMessages";
 
 export default async function refreshHuggingfaceAccessToken_service(
   userId: string,
@@ -34,6 +35,6 @@ export default async function refreshHuggingfaceAccessToken_service(
   }
 
   return ServiceOperationResult.failure(
-    "Failed to refresh user's Huggingface access token"
+    operationsResultsMessages.failedAccessTokenRefreshing
   );
 }

tests/integration/huggingface/refreshHuggingfaceAccessToken.test.ts

@@ -0,0 +1,69 @@
+import { describe, expect, it, afterAll, beforeAll, mock } from "bun:test";
+import databaseConnection from "../../../src/configurations/databaseConnection";
+import huggingfaceService from "../../../src/services/huggingface";
+import DatasetsModel from "../../../src/models/DatasetsModel";
+import operationsResultsMessages from "../../../src/constants/operationsResultsMessages";
+import { fakeUserHuggingfaceAccount } from "../../fake-data/fakeUserHuggingfaceAccount";
+
+beforeAll(async () => {
+  await databaseConnection();
+});
+
+const originalFetch = global.fetch
+
+describe("Test `refreshHuggingfaceAccessToken` service method", () => {
+  it('Should complete refreshing access token process successfully', async () => {
+    const mockFetch = mock(async () => {
+      const payload = {
+        access_token: "-p0__8dso$@pyv94wmm6@#7",
+        refresh_token: "gj%*dqvp082_+9-ym8nmhj",
+        expires_in: 46346
+      }
+      return new Response(JSON.stringify(payload), { status: 200 })
+    })
+
+    global.fetch = mockFetch
+
+    await DatasetsModel.create({
+      _id: process.env.TESTING_USER_ID,
+      huggingfaceAccount: fakeUserHuggingfaceAccount
+    })
+
+    const result = await huggingfaceService.refreshHuggingfaceAccessToken(
+      process.env.TESTING_USER_ID,
+      "f5@*)d#@dSjykgyk*&t84gCk"
+    );
+
+    expect(mockFetch).toHaveBeenCalled()
+    expect(result.isSuccess).toBeTrue();
+    expect(result.result).toMatchObject({
+      accessToken: expect.any(String),
+      accessTokenExpiresIn: expect.any(Date),
+      refreshToken: expect.any(String),
+      username: "anyname",
+      emailVerified: true,
+    });
+  });
+
+  it('Should catch and return an error because of failed external API request', async () => {
+    const mockFetch = mock(async () => {
+      return new Response("{}", { status: 400 })
+    })
+
+    global.fetch = mockFetch
+
+    const result = await huggingfaceService.refreshHuggingfaceAccessToken(
+      process.env.TESTING_USER_ID,
+      "f5@*)d#@dSjykgyk*&t84gCk"
+    );
+
+    expect(mockFetch).toHaveBeenCalled()
+    expect(result.isSuccess).toBeFalse();
+    expect(result.message).toBe(operationsResultsMessages.failedAccessTokenRefreshing);
+  });
+});
+
+afterAll(async () => {
+  global.fetch = originalFetch
+  await DatasetsModel.deleteMany();
+});