(svn r17230) -Fix (r15027): don't assert when an AI uses AI*Mode objects incorrectly but crash the AI instead

2 files changed, 20 insertions, 2 deletions

diff --git a/src/ai/api/ai_execmode.cpp b/src/ai/api/ai_execmode.cpp
index 941718bee..b51adfd48 100644
--- a/src/ai/api/ai_execmode.cpp
+++ b/src/ai/api/ai_execmode.cpp
@@ -4,6 +4,9 @@
 
 #include "ai_execmode.hpp"
 #include "../../command_type.h"
+#include "../../company_base.h"
+#include "../../company_func.h"
+#include "../ai_instance.hpp"
 
 bool AIExecMode::ModeProc(TileIndex tile, uint32 p1, uint32 p2, uint procc, CommandCost costs)
 {
@@ -21,6 +24,12 @@ AIExecMode::AIExecMode()
 
 AIExecMode::~AIExecMode()
 {
-	assert(this->GetDoCommandModeInstance() == this);
+	if (this->GetDoCommandModeInstance() != this) {
+		AIInstance *instance = Company::Get(_current_company)->ai_instance;
+		/* Ignore this error if the AI already died. */
+		if (!instance->IsDead()) {
+			throw AI_FatalError("AIExecMode object was removed while it was not the latest AI*Mode object created.");
+		}
+	}
 	this->SetDoCommandMode(this->last_mode, this->last_instance);
 }
diff --git a/src/ai/api/ai_testmode.cpp b/src/ai/api/ai_testmode.cpp
index 484333b42..114366722 100644
--- a/src/ai/api/ai_testmode.cpp
+++ b/src/ai/api/ai_testmode.cpp
@@ -4,6 +4,9 @@
 
 #include "ai_testmode.hpp"
 #include "../../command_type.h"
+#include "../../company_base.h"
+#include "../../company_func.h"
+#include "../ai_instance.hpp"
 
 bool AITestMode::ModeProc(TileIndex tile, uint32 p1, uint32 p2, uint procc, CommandCost costs)
 {
@@ -21,6 +24,12 @@ AITestMode::AITestMode()
 
 AITestMode::~AITestMode()
 {
-	assert(this->GetDoCommandModeInstance() == this);
+	if (this->GetDoCommandModeInstance() != this) {
+		AIInstance *instance = Company::Get(_current_company)->ai_instance;
+		/* Ignore this error if the AI already died. */
+		if (!instance->IsDead()) {
+			throw AI_FatalError("AITestmode object was removed while it was not the latest AI*Mode object created.");
+		}
+	}
 	this->SetDoCommandMode(this->last_mode, this->last_instance);
 }