Which function do you want to add comments to?

TestBuild in pkg\ddc\alluxio\engine_test.go.

What comments do you want to add?

// TestBuild tests the build function by creating a fake client with predefined test objects.
// It verifies that the engine is successfully built without any errors.
// Parameters:
// - t *testing.T: The testing object used to report test results.
// Returns:
// - None. It reports test failures using t.Errorf if the build function fails.