NG0303：无法绑定到“ngbTooltip”，因为它不是“button”的已知属性

Question

ERROR: 'NG0303: Can't bind to 'ngbTooltip' since it isn't a known property of 'button'.'

When I run tests locally for my Angular 12 project, I get this error, in all .spec files where ngbTooltip is used I use CUSTOM_ELEMENT_SCHEMA , it is impossible to track the line on which the error occurs. It is noteworthy that the error is absent with ng serve , but appears with ng test . Tell me how to solve this problem, I tried using CUSTOM_ELEMENT_SCHEMA in the application module, it did not help.

Console output Console output 2

Answer 1

Try adding NgbModule to imports array in TestBed.configureTestingModule({ .

TestBed.configureTestingModule({
  imports: [NgbModule],
...

If you don't want to import NgbModule or it causes issues in your unit tests, you can mock the directive and provide the mock.

@Directive({
  selector: '[ngbTooltip]'
})
class MockNgbTooltip {}
...
TestBed.configureTestingModule({
  // add the mock to the declarations array
  declarations: [MockNgbTooltip],