Add test for usecase

Author: amitshekhariitbhu

usecase/task_usecase_test.go

@@ -0,0 +1,59 @@
+package usecase_test
+
+import (
+	"context"
+	"errors"
+	"testing"
+	"time"
+
+	"github.com/amitshekhariitbhu/go-backend-clean-architecture/domain"
+	"github.com/amitshekhariitbhu/go-backend-clean-architecture/domain/mocks"
+	"github.com/amitshekhariitbhu/go-backend-clean-architecture/usecase"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/mock"
+	"go.mongodb.org/mongo-driver/bson/primitive"
+)
+
+func TestFetchByUserID(t *testing.T) {
+	mockTaskRepository := new(mocks.TaskRepository)
+	userObjectID := primitive.NewObjectID()
+	userID := userObjectID.Hex()
+
+	t.Run("success", func(t *testing.T) {
+
+		mockTask := domain.Task{
+			ID:     primitive.NewObjectID(),
+			Title:  "Test Title",
+			UserID: userObjectID,
+		}
+
+		mockListTask := make([]domain.Task, 0)
+		mockListTask = append(mockListTask, mockTask)
+
+		mockTaskRepository.On("FetchByUserID", mock.Anything, userID).Return(mockListTask, nil).Once()
+
+		u := usecase.NewTaskUsecase(mockTaskRepository, time.Second*2)
+
+		list, err := u.FetchByUserID(context.Background(), userID)
+
+		assert.NoError(t, err)
+		assert.NotNil(t, list)
+		assert.Len(t, list, len(mockListTask))
+
+		mockTaskRepository.AssertExpectations(t)
+	})
+
+	t.Run("error", func(t *testing.T) {
+		mockTaskRepository.On("FetchByUserID", mock.Anything, userID).Return(nil, errors.New("Unexpected")).Once()
+
+		u := usecase.NewTaskUsecase(mockTaskRepository, time.Second*2)
+
+		list, err := u.FetchByUserID(context.Background(), userID)
+
+		assert.Error(t, err)
+		assert.Nil(t, list)
+
+		mockTaskRepository.AssertExpectations(t)
+	})
+
+}