Unistore Chore: Make it easier to implement DB interface (#94680)

make it easier to implement DB interface

pkg/storage/unified/sql/db/service_test.go

@@ -0,0 +1,97 @@
+package db_test
+
+import (
+	"context"
+	"errors"
+	"testing"
+
+	"github.com/stretchr/testify/mock"
+	"github.com/stretchr/testify/require"
+
+	"github.com/grafana/grafana/pkg/storage/unified/sql/db"
+	"github.com/grafana/grafana/pkg/storage/unified/sql/db/mocks"
+	"github.com/grafana/grafana/pkg/util/testutil"
+)
+
+var errTest = errors.New("you shall not pass")
+
+// Copy-paste of the constants used in `service.go`, since we need to use a
+// separate package to avoid circular dependencies so we cannot import them.
+// Keep these ones and the ones in `service.go` in sync.
+const (
+	txOpStr     = "transactional operation"
+	beginStr    = "begin"
+	commitStr   = "commit"
+	rollbackStr = "rollback"
+)
+
+func TestNewWithTxFunc(t *testing.T) {
+	t.Parallel()
+
+	execTest := func(t *testing.T, d db.DB, txErr error) error {
+		ctx := testutil.NewDefaultTestContext(t)
+		return db.NewWithTxFunc(d.BeginTx).WithTx(ctx, nil,
+			func(context.Context, db.Tx) error {
+				return txErr
+			})
+	}
+
+	t.Run("happy path", func(t *testing.T) {
+		t.Parallel()
+		mDB, mTx := mocks.NewDB(t), mocks.NewTx(t)
+
+		mDB.EXPECT().BeginTx(mock.Anything, mock.Anything).Return(mTx, nil)
+		mTx.EXPECT().Commit().Return(nil)
+
+		err := execTest(t, mDB, nil)
+		require.NoError(t, err)
+	})
+
+	t.Run("failed begin", func(t *testing.T) {
+		t.Parallel()
+		mDB := mocks.NewDB(t)
+
+		mDB.EXPECT().BeginTx(mock.Anything, mock.Anything).Return(nil, errTest)
+
+		err := execTest(t, mDB, nil)
+		require.Error(t, err)
+		require.ErrorContains(t, err, beginStr)
+	})
+
+	t.Run("fail tx", func(t *testing.T) {
+		t.Parallel()
+		mDB, mTx := mocks.NewDB(t), mocks.NewTx(t)
+
+		mDB.EXPECT().BeginTx(mock.Anything, mock.Anything).Return(mTx, nil)
+		mTx.EXPECT().Rollback().Return(nil)
+
+		err := execTest(t, mDB, errTest)
+		require.Error(t, err)
+		require.ErrorContains(t, err, txOpStr)
+	})
+
+	t.Run("fail tx; fail rollback", func(t *testing.T) {
+		t.Parallel()
+		mDB, mTx := mocks.NewDB(t), mocks.NewTx(t)
+
+		mDB.EXPECT().BeginTx(mock.Anything, mock.Anything).Return(mTx, nil)
+		mTx.EXPECT().Rollback().Return(errTest)
+
+		err := execTest(t, mDB, errTest)
+		require.Error(t, err)
+		require.ErrorContains(t, err, txOpStr)
+		require.ErrorContains(t, err, rollbackStr)
+	})
+
+	t.Run("fail commit", func(t *testing.T) {
+		t.Parallel()
+		mDB, mTx := mocks.NewDB(t), mocks.NewTx(t)
+
+		mDB.EXPECT().BeginTx(mock.Anything, mock.Anything).Return(mTx, nil)
+		mTx.EXPECT().Commit().Return(errTest)
+
+		err := execTest(t, mDB, nil)
+		require.Error(t, err)
+		require.ErrorContains(t, err, commitStr)
+	})
+}