This is a minial reproduction of an behaviour that only occurs in tests if a component has a selector consiting of an element and an attritute part (e.g. app-test[inputAttribute] where inputAttribute is an component's attribute). The Implementation can be found here
One jasmine test of the component TestComponent fails because the input will be set to an empty string allthough a value das set before.
Run ng test to start the tests or run ng serve -o to check the behaviour in a running Angular Application.