emi-challenge-fe/tests/app/features/tasks/data-access/services/task.spec.ts

import { describe, it, expect, vi, beforeEach } from 'vitest';
import { TestBed } from '@angular/core/testing';
import { of } from 'rxjs';
import { TaskService } from '@app/features/tasks/data-access/services/task';
import { TaskDataSource } from '@app/features/tasks/data-access/data-sources/task-data-source.interface';
import { TASK_DATA_SOURCE } from '@app/features/tasks/data-access/data-sources/task-data-source.token';
import { TaskBuilder } from '@tests/builders/task.builder';

describe('TaskService', () => {
  let service: TaskService;
  let dataSource: TaskDataSource;

  beforeEach(() => {
    dataSource = {
      getAll: vi.fn(),
      getById: vi.fn(),
      create: vi.fn(),
      update: vi.fn(),
      delete: vi.fn(),
      transition: vi.fn(),
      addNote: vi.fn(),
      deleteNote: vi.fn(),
    };

    TestBed.configureTestingModule({
      providers: [
        TaskService,
        { provide: TASK_DATA_SOURCE, useValue: dataSource },
      ],
    });

    service = TestBed.inject(TaskService);
  });

  describe('getAll', () => {
    it('should return paginated tasks from datasource', () => {
      const tasks = TaskBuilder.buildMany(3);
      const response = { data: tasks, pagination: { page: 1, pageSize: 10, total: 3, totalPages: 1 } };
      vi.mocked(dataSource.getAll).mockReturnValue(of(response));

      service.getAll().subscribe(result => {
        expect(result).toEqual(response);
      });

      expect(dataSource.getAll).toHaveBeenCalledOnce();
    });

    it('should pass pagination params to datasource', () => {
      const params = { page: 2, pageSize: 5 };
      const response = { data: [], pagination: { page: 2, pageSize: 5, total: 0, totalPages: 0 } };
      vi.mocked(dataSource.getAll).mockReturnValue(of(response));

      service.getAll(params).subscribe();

      expect(dataSource.getAll).toHaveBeenCalledWith(params);
    });
  });

  describe('getById', () => {
    it('should return task by id from datasource', () => {
      const task = new TaskBuilder().withId('task-1').build();
      vi.mocked(dataSource.getById).mockReturnValue(of(task));

      service.getById('task-1').subscribe(result => {
        expect(result).toEqual(task);
      });

      expect(dataSource.getById).toHaveBeenCalledWith('task-1');
    });
  });

  describe('create', () => {
    it('should create task through datasource', () => {
      const dto = { title: 'New Task', description: 'Description' };
      const created = new TaskBuilder().withTitle('New Task').build();
      vi.mocked(dataSource.create).mockReturnValue(of(created));

      service.create(dto).subscribe(result => {
        expect(result).toEqual(created);
      });

      expect(dataSource.create).toHaveBeenCalledWith(dto);
    });
  });

  describe('update', () => {
    it('should update task through datasource', () => {
      const dto = { title: 'Updated' };
      const updated = new TaskBuilder().withId('task-1').withTitle('Updated').build();
      vi.mocked(dataSource.update).mockReturnValue(of(updated));

      service.update('task-1', dto).subscribe(result => {
        expect(result).toEqual(updated);
      });

      expect(dataSource.update).toHaveBeenCalledWith('task-1', dto);
    });
  });

  describe('delete', () => {
    it('should delete task through datasource', () => {
      vi.mocked(dataSource.delete).mockReturnValue(of(undefined));

      service.delete('task-1').subscribe();

      expect(dataSource.delete).toHaveBeenCalledWith('task-1');
    });
  });

  describe('transition', () => {
    it('should transition task state through datasource', () => {
      const updated = new TaskBuilder().withId('task-1').withState('active').build();
      vi.mocked(dataSource.transition).mockReturnValue(of(updated));

      service.transition('task-1', 'active').subscribe(result => {
        expect(result).toEqual(updated);
      });

      expect(dataSource.transition).toHaveBeenCalledWith('task-1', 'active');
    });
  });

  describe('addNote', () => {
    it('should add note through datasource', () => {
      const updated = new TaskBuilder().withId('task-1').withNotes(['New note']).build();
      vi.mocked(dataSource.addNote).mockReturnValue(of(updated));

      service.addNote('task-1', 'New note').subscribe(result => {
        expect(result).toEqual(updated);
      });

      expect(dataSource.addNote).toHaveBeenCalledWith('task-1', 'New note');
    });
  });

  describe('deleteNote', () => {
    it('should delete note through datasource', () => {
      const updated = new TaskBuilder().withId('task-1').withNotes([]).build();
      vi.mocked(dataSource.deleteNote).mockReturnValue(of(updated));

      service.deleteNote('task-1', 0).subscribe(result => {
        expect(result).toEqual(updated);
      });

      expect(dataSource.deleteNote).toHaveBeenCalledWith('task-1', 0);
    });
  });
});