Pact consumer tests in angular and HttpIntercepter - karma-runner

Question

Our application uses HttpInterceptor to convert JSON properties from camel-case to snake-case.
I configure pact in karma.conf.js and set pact proxy there.
For my test I use TestBed:
TestBed.configureTestingModule({
imports: [
HttpClientModule
],
providers: [
EmployeeService,
{ provide: SERVER_URLS, useValue: TokenPactMock.SERVER_URLS() },
{ provide: HTTP_RETRY_ATTEMPTS, useValue: TokenMock.HTTP_RETRY_ATTEMPTS() }
],
});
and this is my test:
const employeeService: EmployeeService = TestBed.get(EmployeeServiceService);
employeeService.addEmployee(employee).subscribe(response => {
expect(response.status).toEqual(201);
expect(response.body).toEqual(employee);
done();
}, error => {
done.fail(error);
});
This test runs successfully and pact file is generated. But HttpInterceptor was not trigger and in PACT file I have camel-case properties instead of snake-case.
Does anybody know how to use PACT with HttpInterceptor?

Answer 1

We have found the answer. It was our misunderstanding of difference between HttpClientModule and HttpClientTestingModule.
In HttpClientModule we must explicitly define our listeners:
TestBed.configureTestingModule({
imports: [
HttpClientModule
],
providers: [
EmployeeService,
{ provide: SERVER_URLS, useValue: TokenPactMock.SERVER_URLS() },
{ provide: HTTP_INTERCEPTORS, useClass: HttpNamingInterceptor, multi: true },
{ provide: HTTP_RETRY_ATTEMPTS, useValue: TokenMock.HTTP_RETRY_ATTEMPTS() }
],
});