Added reference tracking (#26900)

__DEFINES/__compile_options.dm

@@ -52,3 +52,5 @@
 
 // I wonder what this does
 #define SHOW_CHANGELOG_ON_NEW_PLAYER_LOGIN !DEVELOPER_MODE
+
+#define EXTOOLS_REFERENCE_TRACKING DEVELOPER_MODE

code/datums/datumvars.dm

@@ -144,7 +144,9 @@
 		body += "<option value='?_src_=vars;toggle_aliasing=\ref[D]'>Toggle Transform Aliasing</option>"
 
 	body += "<option value='?_src_=vars;proc_call=\ref[D]'>Proc call</option>"
-
+	#if EXTOOLS_REFERENCE_TRACKING
+	body += "<option value='?_src_=vars;view_references=\ref[D]'>View references</option>"
+	#endif
 	body += "<option value>---</option>"
 
 	if(ismob(D))
@@ -859,7 +861,7 @@ function loadPage(list) {
 			if ("Monolith")
 				rod_type = /obj/item/projectile/immovablerod/hyper
 
-		if(alert("Are you sure you want to do this?","Confirm","Yes","No") != "Yes")	
+		if(alert("Are you sure you want to do this?","Confirm","Yes","No") != "Yes")
 			return
 
 		var/obj/item/projectile/immovablerod/rod = new rod_type(random_start_turf(A.z))
@@ -1157,7 +1159,17 @@ function loadPage(list) {
 			return
 
 		callatomproc(DAT)	//Yes it could be a datum, technically but eh
+	#if EXTOOLS_REFERENCE_TRACKING
+	else if(href_list["view_references"])
+		if(!check_rights(R_DEBUG))
+			return
 
+		var/datum/target = locate(href_list["view_references"])
+		if(!target)
+			return
+
+		usr.client.view_refs(target)
+	#endif
 	else if (href_list["edit_transform"])
 		if (!check_rights(R_DEBUG))
 			return

code/datums/reference_tracking.dm

@@ -0,0 +1,45 @@
+#if EXTOOLS_REFERENCE_TRACKING
+
+/proc/get_back_references(datum/D)
+	CRASH("/proc/get_back_references not hooked by extools, reference tracking will not function!")
+
+/proc/get_forward_references(datum/D)
+	CRASH("/proc/get_forward_references not hooked by extools, reference tracking will not function!")
+
+/client/verb/view_refs(atom/D) //it actually supports datums as well but byond no likey
+	set category = "Debug"
+	set name = "View References"
+
+	var/list/backrefs = get_back_references(D)
+	if(isnull(backrefs))
+		usr << browse("Reference tracking not enabled", "window=ref_view")
+		return
+	var/list/frontrefs = get_forward_references(D)
+	var/list/dat = list()
+	dat += "<h1>References of \ref[D] - [D]</h1><br><a href='?_src_=vars;view_references=[ref(D)]'>\[Refresh\]</a><hr>"
+	dat += "<h3>Back references - these things hold references to this object.</h3>"
+	dat += "<table>"
+	dat += "<tr><th>Ref</th><th>Type</th><th>Variable Name</th><th>Follow</th>"
+	for(var/ref in backrefs)
+		var/datum/R = ref
+		dat += "<tr><td><a href='?_src_=vars;Vars=[ref(R)]'>"
+		dat += "[ref(R)]</td>"
+		try
+			dat += "<td>[R.type]</td>"
+		catch
+			dat += "<td>RUNTIME ERROR</td>"
+		dat += "<td>[backrefs[R]]</td>"
+		dat += "<td><a href='?_src_=vars;view_references=[ref(R)]'>\[Follow\]</a></td></tr>"
+	dat += "</table><hr>"
+	dat += "<h3>Forward references - this object is referencing those things.</h3>"
+	dat += "<table>"
+	dat += "<tr><th>Variable name</th><th>Ref</th><th>Type</th><th>Follow</th>"
+	for(var/ref in frontrefs)
+		var/datum/R = frontrefs[ref]
+		dat += "<tr><td>[ref]</td><td><a href='?_src_=vars;Vars=[ref(R)]'>[ref(R)]</a></td><td>[R.type]</td><td><a href='?_src_=vars;view_references=[ref(R)]'>\[Follow\]</a></td></tr>"
+	dat += "</table><hr>"
+	dat = dat.Join()
+
+	usr << browse(dat, "window=ref_view;size=800x500")
+
+#endif

code/world.dm

@@ -20,6 +20,9 @@ var/savefile/panicfile
 	var/extools_path = system_type == MS_WINDOWS ? "byond-extools.dll" : "libbyond-extools.so"
 	if(fexists(extools_path))
 		call(extools_path, "maptick_initialize")()
+		#if EXTOOLS_REFERENCE_TRACKING
+		call(extools_path, "ref_tracking_initialize")()
+		#endif
 	else
 		// warn on missing library
 		// extools on linux does not exist and is not in the repository as of yet

vgstation13.dme

@@ -265,6 +265,7 @@
 #include "code\datums\profiling.dm"
 #include "code\datums\recipe.dm"
 #include "code\datums\recruiter.dm"
+#include "code\datums\reference_tracking.dm"
 #include "code\datums\religions.dm"
 #include "code\datums\shuttle.dm"
 #include "code\datums\sun.dm"