@Test
    public void testMissingUsernamePasswordAuthenticator() {
        val digestAuthClient = new DirectDigestAuthClient(null);
        TestsHelper.expectException(() -> digestAuthClient.getCredentials(new CallContext(MockWebContext.create(),
                new MockSessionStore())), TechnicalException.class, "authenticator cannot be null");
    }
This class tests the {@link DirectDigestAuthClient} class.

@author Mircea Carasel
@since 1.9.0
pac4j-http/src/test/java/org/pac4j/http/client/direct/DirectDigestAuthClientTests.java