fix: spell range on south walls (#3412)

Author: kaleohanopahala

src/utils/tools.cpp

@@ -15,6 +15,7 @@
 #include "lua/lua_definitions.hpp"
 #include "utils/const.hpp"
 #include "config/configmanager.hpp"
+#include "game/movement/position.hpp"
 
 #include "absl/debugging/stacktrace.h"
 #include "absl/debugging/symbolize.h"
@@ -570,6 +571,10 @@ Position getNextPosition(Direction direction, Position pos) {
 }
 
 Direction getDirectionTo(const Position &from, const Position &to, bool exactDiagonalOnly /* =true*/) {
+	if (from == to) {
+		return DIRECTION_NONE;
+	}
+
 	const int_fast32_t dx = Position::getOffsetX(from, to);
 	const int_fast32_t dy = Position::getOffsetY(from, to);
 

tests/unit/utils/position_functions_test.cpp

@@ -18,9 +18,9 @@ suite<"utils"> getDirectionToTest = [] {
 	};
 
 	std::vector getDirectionToTestCases {
-		GetDirectionToTestCase { Position {}, Position {}, DIRECTION_SOUTH, DIRECTION_SOUTH },
-		GetDirectionToTestCase { Position { 0, 0, 0 }, Position { 0, 0, 0 }, DIRECTION_SOUTH, DIRECTION_SOUTH },
-		GetDirectionToTestCase { Position { 100, 100, 100 }, Position { 100, 100, 100 }, DIRECTION_SOUTH, DIRECTION_SOUTH },
+		GetDirectionToTestCase { Position {}, Position {}, DIRECTION_NONE, DIRECTION_NONE },
+		GetDirectionToTestCase { Position { 0, 0, 0 }, Position { 0, 0, 0 }, DIRECTION_NONE, DIRECTION_NONE },
+		GetDirectionToTestCase { Position { 100, 100, 100 }, Position { 100, 100, 100 }, DIRECTION_NONE, DIRECTION_NONE },
 		GetDirectionToTestCase { Position { 125, 1123, 5 }, Position { 125, 1153, 5 }, DIRECTION_SOUTH, DIRECTION_SOUTH },
 		GetDirectionToTestCase { Position { 5555, 3212, 15 }, Position { 5555, 3211, 15 }, DIRECTION_NORTH, DIRECTION_NORTH },
 		GetDirectionToTestCase { Position { 32132, 65000, 11 }, Position { 31512, 65000, 11 }, DIRECTION_WEST, DIRECTION_WEST },