[MIRROR] Fixes hearing messages from speakers on another z level (515 fix) [MDB IGNORE] (#25217)

* Fixes hearing messages from speakers on another z level (515 fix) (#79888)

515 changed get_dist to return inf when either end is on another z
level, instead of just the maximum range. `/mob/living/Hear` early
returns when the speaker is too far away to hear. Previously we would
get around this by passing in INFINITY as the range for the message, but
the INFINITY define is just a very large number instead of real infinity
which is what byond gives back for get_dist.

I also improved the unit test a little while debugging this.

* Fixes hearing messages from speakers on another z level (515 fix)

---------

Co-authored-by: Emmett Gaines <ninjanomnom@gmail.com>

code/modules/unit_tests/say.dm

@@ -58,12 +58,15 @@
 
 /// This runs some simple speech tests on a speaker and listener and determines if a person can hear whispering or speaking as they are moved a distance away
 /datum/unit_test/speech
-	var/list/handle_speech_result = null
-	var/list/handle_hearing_result = null
 	var/mob/living/carbon/human/speaker
 	var/mob/living/carbon/human/listener
+	var/list/handle_speech_result = null
+	var/list/handle_hearing_result = null
+
 	var/obj/item/radio/speaker_radio
 	var/obj/item/radio/listener_radio
+	var/speaker_radio_heard_message = FALSE
+	var/listener_radio_received_message = FALSE
 
 /datum/unit_test/speech/proc/handle_speech(datum/source, list/speech_args)
 	SIGNAL_HANDLER
@@ -99,6 +102,16 @@
 	handle_hearing_result = list()
 	handle_hearing_result += hearing_args
 
+/datum/unit_test/speech/proc/handle_radio_hearing(datum/source, mob/living/user, message, channel)
+	SIGNAL_HANDLER
+
+	speaker_radio_heard_message = TRUE
+
+/datum/unit_test/speech/proc/handle_radio_speech(datum/source, list/data)
+	SIGNAL_HANDLER
+
+	listener_radio_received_message = TRUE
+
 /datum/unit_test/speech/Run()
 	speaker = allocate(/mob/living/carbon/human/consistent)
 	// Name changes to make understanding breakpoints easier
@@ -114,7 +127,10 @@
 	listener.mock_client = mock_client
 
 	RegisterSignal(speaker, COMSIG_MOB_SAY, PROC_REF(handle_speech))
+	RegisterSignal(speaker_radio, COMSIG_RADIO_NEW_MESSAGE, PROC_REF(handle_radio_hearing))
+
 	RegisterSignal(listener, COMSIG_MOVABLE_HEAR, PROC_REF(handle_hearing))
+	RegisterSignal(listener_radio, COMSIG_RADIO_RECEIVE_MESSAGE, PROC_REF(handle_radio_speech))
 
 	// speaking and whispering should be hearable
 	conversation(distance = 1)
@@ -169,6 +185,9 @@
 	handle_hearing_result = null
 
 /datum/unit_test/speech/proc/radio_test()
+	speaker_radio_heard_message = FALSE
+	listener_radio_received_message = FALSE
+
 	speaker.forceMove(run_loc_floor_bottom_left)
 	listener.forceMove(locate((run_loc_floor_bottom_left.x + 10), run_loc_floor_bottom_left.y, run_loc_floor_bottom_left.z))
 
@@ -186,11 +205,15 @@
 
 	speaker.say(pangram_quote)
 	TEST_ASSERT(handle_speech_result, "Handle speech signal was not fired (radio test)")
-	TEST_ASSERT(islist(handle_hearing_result), "Listener failed to hear radio message (radio test)")
+	TEST_ASSERT(speaker_radio_heard_message, "Speaker's radio did not hear them speak (radio test)")
 	TEST_ASSERT_EQUAL(speaker_radio.get_frequency(), listener_radio.get_frequency(), "Radio frequencies were not equal (radio test)")
+	TEST_ASSERT(listener_radio_received_message, "Listener's radio did not receive the broadcast (radio test)")
+	TEST_ASSERT(islist(handle_hearing_result), "Listener failed to hear radio message (radio test)")
 
 	handle_speech_result = null
 	handle_hearing_result = null
+	speaker_radio_heard_message = FALSE
+	listener_radio_received_message = FALSE
 
 	speaker_radio.set_frequency(FREQ_CTF_RED)
 	speaker.say(pangram_quote)
@@ -200,6 +223,8 @@
 
 	handle_speech_result = null
 	handle_hearing_result = null
+	speaker_radio_heard_message = FALSE
+	listener_radio_received_message = FALSE
 	speaker_radio.set_broadcasting(FALSE)
 
 #undef NORMAL_HEARING_RANGE