How write Junit test for custom Authentication Provider

Question

I have a custom Ldap Authentication provider which is not called during my tests due to the mocks(I think). Is there any way to write junit testcases for Authentication provider implementation? Test passes but custom authentication provider configured in security configuration is not called!

Spring config:

@Configuration
@EnableWebSecurity
@RequiredArgsConstructor
public class SecurityConfiguration {

    @Autowired
    private final LdapAuthenticationProvider ldapAuthenticationProvider;

    @Bean
    public SecurityFilterChain filterChain(HttpSecurity http) throws Exception {
        http.csrf(AbstractHttpConfigurer::disable)
        .cors(httpSecurityCorsConfigurer -> httpSecurityCorsConfigurer.configurationSource(corsConfigurationSource()))
        .authorizeHttpRequests(request -> request.requestMatchers("/api/v1/4g/**")
                .permitAll().anyRequest().authenticated())
            .sessionManagement(manager -> manager.sessionCreationPolicy(STATELESS));
        return http.build();
    }
    
    @Bean
    AuthenticationManager authenticationManager(
        AuthenticationConfiguration authenticationConfiguration) throws Exception {
        return authenticationConfiguration.getAuthenticationManager();
    }

    @Autowired
    void registerProvider(AuthenticationManagerBuilder auth) {
        auth.authenticationProvider(ldapAuthenticationProvider);
    }

    @Bean
    public PasswordEncoder passwordEncoder() {
        return new BCryptPasswordEncoder();
    }    
}

Authentication provider:

public class LdapAuthenticationProvider implements AuthenticationProvider{
    @Override
    public Authentication authenticate(Authentication authentication) throws AuthenticationException {
        String username = authentication.getName();
        String password = authentication.getCredentials().toString();
        ... SOME AUTHENTICATION LOGIC HERE ...
        return authenticated;
    }

    @Override
    public boolean supports(Class<?> authentication) {
        return authentication.equals(UsernamePasswordAuthenticationToken.class);
    }

}

JUnit Test

@ExtendWith(SpringExtension.class)
@WebMvcTest(controllers = LoginController.class)
@Import(LoginController.class)
@AutoConfigureMockMvc
@ContextConfiguration(classes = {Application.class})
public class LdapAuthenticationProviderTest {
    @InjectMocks
    private LoginController loginController;
    @Autowired
    private MockMvc mockMvc;

    private static final String USERNAME = "username";
    private static final String PASSWORD = "password";
    @TestConfiguration
    static class AdditionalConfig {
        @Bean
        public LdapAuthenticationProvider ldapProvider() {
            return new LdapAuthenticationProvider();
        }
    }
    @BeforeEach
    void init(){
        InternalResourceViewResolver viewResolver = new InternalResourceViewResolver();
        viewResolver.setPrefix("/4gapp/");
        MockitoAnnotations.openMocks(loginController);
        mockMvc = MockMvcBuilders
                .standaloneSetup(loginController)
                .setViewResolvers(viewResolver)
                .alwaysDo(print())
                .build();
    }
    @Test
    public void ldapAuthProviderTest() throws Exception {
        ObjectMapper objectMapper = new ObjectMapper();

        mockMvc.perform(post("/api/v1/4g/login")
                        .contentType(MediaType.APPLICATION_JSON)
                        .content(objectMapper.writeValueAsString(request)))
                .andExpect(status().isOk())
                .andReturn();
    }
}