Tweaks after reviewing Zed's version

lcthw-remnants-2/liblcthw/src/lcthw/list_algos.c

@@ -1,9 +1,14 @@
 #include <lcthw/list_algos.h>
+#include <lcthw/dbg.h>
 
 int List_bubble_sort(List *list, List_compare cmp)
 {
   List_validate(list);
 
+  if(List_count(list) <= 1) {
+    return 0;
+  }
+
   int swapped = 1;
 
   while(swapped == 1) {
@@ -24,7 +29,7 @@ int List_bubble_sort(List *list, List_compare cmp)
   return 0;
 }
 
-List *_List_merge_sort_merge(List *left, List *right, List_compare cmp)
+List *List_merge(List *left, List *right, List_compare cmp)
 {
   List *result = List_create();
 
@@ -51,7 +56,7 @@ List *_List_merge_sort_merge(List *left, List *right, List_compare cmp)
 List *List_merge_sort(List *list, List_compare cmp)
 {
   if(List_count(list) <= 1) {
-    return List_copy(list);;
+    return list;;
   }
 
   int i = 0;
@@ -67,13 +72,16 @@ List *List_merge_sort(List *list, List_compare cmp)
     i++;
   }
 
-  left = List_merge_sort(left, cmp);
-  right = List_merge_sort(right, cmp);
+  List *sort_left = List_merge_sort(left, cmp);
+  List *sort_right = List_merge_sort(right, cmp);
 
-  List *result = _List_merge_sort_merge(left, right, cmp);
+  if(sort_left != left) {
+    List_destroy(left);
+  }
 
-  List_destroy(left);
-  List_destroy(right);
+  if(sort_right != right) {
+    List_destroy(right);
+  }
 
-  return result;
+  return List_merge(sort_left, sort_right, cmp);
 }