From b335b0501cba1765ec97e89da828942cd925a1e9 Mon Sep 17 00:00:00 2001
From: SamuXarick <43006711+SamuXarick@users.noreply.github.com>
Date: Sat, 18 Sep 2021 11:46:20 +0100
Subject: [PATCH] Fix: wrong error message when building canals over ship
 depots / locks

IsTileType() also considers ship depots and locks water. IsWaterTile() does the right thing.
---
 src/water_cmd.cpp | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/water_cmd.cpp b/src/water_cmd.cpp
index 6906f744b9..a661cb38ca 100644
--- a/src/water_cmd.cpp
+++ b/src/water_cmd.cpp
@@ -475,10 +475,11 @@ CommandCost CmdBuildCanal(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32
 			return_cmd_error(STR_ERROR_FLAT_LAND_REQUIRED);
 		}
 
-		/* can't make water of water! */
-		if (IsTileType(current_tile, MP_WATER) && (!IsTileOwner(current_tile, OWNER_WATER) || wc == WATER_CLASS_SEA)) continue;
-
 		bool water = IsWaterTile(current_tile);
+
+		/* can't make water of water! */
+		if (water && (!IsTileOwner(current_tile, OWNER_WATER) || wc == WATER_CLASS_SEA)) continue;
+
 		ret = DoCommand(current_tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
 		if (ret.Failed()) return ret;