From 5a1e7bdefa9a42b3f0f34912bee34413c19d8979 Mon Sep 17 00:00:00 2001
From: Heroman3003 <31296024+Heroman3003@users.noreply.github.com>
Date: Sat, 29 Oct 2022 16:35:22 +1000
Subject: [PATCH] Merge pull request #13909 from
 VOREStation/upstream-merge-8737

[MIRROR] fix || in type2parent switch, gentle refactor
---
 code/_helpers/type2type.dm | 123 +++++++++++++++++++++++++++++++++----
 1 file changed, 112 insertions(+), 11 deletions(-)

diff --git a/code/_helpers/type2type.dm b/code/_helpers/type2type.dm
index ef25f44142..e21d973b1b 100644
--- a/code/_helpers/type2type.dm
+++ b/code/_helpers/type2type.dm
@@ -293,21 +293,122 @@
 		return strtype
 	return copytext(strtype, delim_pos)
 
+// Concatenates a list of strings into a single string.  A seperator may optionally be provided.
+/proc/list2text(list/ls, sep)
+	if (ls.len <= 1) // Early-out code for empty or singleton lists.
+		return ls.len ? ls[1] : ""
+
+	var/l = ls.len // Made local for sanic speed.
+	var/i = 0      // Incremented every time a list index is accessed.
+
+	if (sep != null)
+		// Macros expand to long argument lists like so: sep, ls[++i], sep, ls[++i], sep, ls[++i], etc...
+		#define S1  sep, ls[++i]
+		#define S4  S1,  S1,  S1,  S1
+		#define S16 S4,  S4,  S4,  S4
+		#define S64 S16, S16, S16, S16
+
+		. = "[ls[++i]]" // Make sure the initial element is converted to text.
+
+		// Having the small concatenations come before the large ones boosted speed by an average of at least 5%.
+		if (l-1 & 0x01) // 'i' will always be 1 here.
+			. = text("[][][]", ., S1) // Append 1 element if the remaining elements are not a multiple of 2.
+		if (l-i & 0x02)
+			. = text("[][][][][]", ., S1, S1) // Append 2 elements if the remaining elements are not a multiple of 4.
+		if (l-i & 0x04)
+			. = text("[][][][][][][][][]", ., S4) // And so on....
+		if (l-i & 0x08)
+			. = text("[][][][][][][][][][][][][][][][][]", ., S4, S4)
+		if (l-i & 0x10)
+			. = text("[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]", ., S16)
+		if (l-i & 0x20)
+			. = text("[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]\
+			          [][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]", ., S16, S16)
+		if (l-i & 0x40)
+			. = text("[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]\
+			          [][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]\
+			          [][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]\
+			          [][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]", ., S64)
+		while (l > i) // Chomp through the rest of the list, 128 elements at a time.
+			. = text("[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]\
+			          [][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]\
+			          [][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]\
+			          [][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]\
+			          [][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]\
+			          [][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]\
+			          [][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]\
+			          [][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]", ., S64, S64)
+
+		#undef S64
+		#undef S16
+		#undef S4
+		#undef S1
+	else
+		// Macros expand to long argument lists like so: ls[++i], ls[++i], ls[++i], etc...
+		#define S1  ls[++i]
+		#define S4  S1,  S1,  S1,  S1
+		#define S16 S4,  S4,  S4,  S4
+		#define S64 S16, S16, S16, S16
+
+		. = "[ls[++i]]" // Make sure the initial element is converted to text.
+
+		if (l-1 & 0x01) // 'i' will always be 1 here.
+			. += S1 // Append 1 element if the remaining elements are not a multiple of 2.
+		if (l-i & 0x02)
+			. = text("[][][]", ., S1, S1) // Append 2 elements if the remaining elements are not a multiple of 4.
+		if (l-i & 0x04)
+			. = text("[][][][][]", ., S4) // And so on...
+		if (l-i & 0x08)
+			. = text("[][][][][][][][][]", ., S4, S4)
+		if (l-i & 0x10)
+			. = text("[][][][][][][][][][][][][][][][][]", ., S16)
+		if (l-i & 0x20)
+			. = text("[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]", ., S16, S16)
+		if (l-i & 0x40)
+			. = text("[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]\
+			          [][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]", ., S64)
+		while (l > i) // Chomp through the rest of the list, 128 elements at a time.
+			. = text("[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]\
+			          [][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]\
+			          [][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]\
+			          [][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]", ., S64, S64)
+
+		#undef S64
+		#undef S16
+		#undef S4
+		#undef S1
+
+// Converts a string into a list by splitting the string at each delimiter found. (discarding the seperator)
+/proc/text2list(text, delimiter="\n")
+	var/delim_len = length(delimiter)
+	if (delim_len < 1)
+		return list(text)
+
+	. = list()
+	var/last_found = 1
+	var/found
+
+	do
+		found       = findtext(text, delimiter, last_found, 0)
+		.          += copytext(text, last_found, found)
+		last_found  = found + delim_len
+	while (found)
+
 /proc/type2parent(child)
 	var/string_type = "[child]"
 	var/last_slash = findlasttext(string_type, "/")
-	if(last_slash == 1)
-		switch(child)
-			if(/datum)
-				return null
-			if(/obj || /mob)
-				return /atom/movable
-			if(/area || /turf)
-				return /atom
-			else
-				return /datum
+	if (last_slash != 1)
+		return text2path(copytext(string_type, 1, last_slash))
+	switch (child)
+		if (/datum)
+			return null
+		if (/obj, /mob)
+			return /atom/movable
+		if (/area, /turf)
+			return /atom
+		else
+			return /datum
 
-	return text2path(copytext(string_type, 1, last_slash))
 
 //checks if a file exists and contains text
 //returns text as a string if these conditions are met