From 37d318c41098f128924e1fa3369492594a9ce6c3 Mon Sep 17 00:00:00 2001
From: Tyler Trahan <tyler@tylertrahan.com>
Date: Wed, 11 May 2022 17:59:57 -0600
Subject: [PATCH] Fix #9870: Don't update infrastructure totals when
 overbuilding object on canal

---
 src/water_cmd.cpp | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/water_cmd.cpp b/src/water_cmd.cpp
index 6d26888d14..211e89b4a0 100644
--- a/src/water_cmd.cpp
+++ b/src/water_cmd.cpp
@@ -495,11 +495,14 @@ CommandCost CmdBuildCanal(DoCommandFlag flags, TileIndex tile, TileIndex start_t
 					FALLTHROUGH;
 
 				default:
-					MakeCanal(current_tile, _current_company, Random());
-					if (Company::IsValidID(_current_company)) {
+					/* If we overbuild a water object with a canal, don't update the infrastructure total. */
+					bool is_existing_canal = IsTileType(current_tile, MP_WATER) && IsCanal(current_tile);
+					if (Company::IsValidID(_current_company) && !is_existing_canal) {
 						Company::Get(_current_company)->infrastructure.water++;
 						DirtyCompanyInfrastructureWindows(_current_company);
 					}
+
+					MakeCanal(current_tile, _current_company, Random());
 					break;
 			}
 			MarkTileDirtyByTile(current_tile);