Support empty cotext ReactorContextTestExecutionListener pass Security

[bakomchik]

I would like to have option to pass SecurityContextHolder.createEmptyContext() into my reactor test

Expected Behavior
Test passed

@ExtendWith(SpringExtension::class)
@TestExecutionListeners(
    WithSecurityContextTestExecutionListener::class,
    ReactorContextTestExecutionListener::class
)
internal class SpringSecurityIdentityProviderTest {
    @Test
    @WithEmptySecurityContext
    fun `when security context is empty then context should be passed to test`() {
        Mono.defer {
            ReactiveSecurityContextHolder.getContext()
                .onEmptyError { IllegalStateException("Require security context") }
                .filter { it.authentication == null }
        }.onEmptyError { IllegalStateException("Require security context with Empty auth") }
            .block()
    }
}



class EmptySecurityContextFactory : WithSecurityContextFactory<WithEmptySecurityContext> {
    override fun createSecurityContext(annotation: WithEmptySecurityContext?): SecurityContext {
        return SecurityContextHolder.createEmptyContext()
    }

}
@WithSecurityContext(factory = EmptySecurityContextFactory::class)
annotation class WithEmptySecurityContext

Current Behavior

test failed

Context

Sometime we receive empty SecurityContext in our logic and would like to have option to test these cases.
But ReactorContextTestExecutionListener do not pass empty SecurityContext to tests.
Workaround is to modify stream context like this:

   Mono.defer {
            ReactiveSecurityContextHolder.getContext()
                .onEmptyError { IllegalStateException("Require security context") }
                .filter { it.authentication == null }
        }.onEmptyError { IllegalStateException("Require security context with Empty auth") }
            .contextWrite({
                val withSecurityContext = ReactiveSecurityContextHolder.withSecurityContext(
                    Mono.just(SecurityContextHolder.createEmptyContext())
                )
                withSecurityContext.putAll(it.readOnly())
                withSecurityContext
            })
            .block()