From d25baf7bd3c53a89ddfe0b9a2992cf1967e18187 Mon Sep 17 00:00:00 2001
From: Ted John <ted@brambles.org>
Date: Sat, 16 Jul 2016 14:12:16 +0100
Subject: [PATCH] improve assertion messages

---
 src/core/Console.cpp |  8 ++++++--
 src/core/Console.hpp |  1 +
 src/core/Guard.cpp   | 49 ++++++++++++++++++++++++++++++++++++++++----
 src/core/Guard.hpp   | 24 ++++++++++++++++------
 4 files changed, 70 insertions(+), 12 deletions(-)

diff --git a/src/core/Console.cpp b/src/core/Console.cpp
index d82064022d..5c75d249a0 100644
--- a/src/core/Console.cpp
+++ b/src/core/Console.cpp
@@ -94,11 +94,15 @@ namespace Console
         void WriteLine(const utf8 * format, ...)
         {
             va_list args;
-
             va_start(args, format);
+            WriteLine_VA(format, args);
+            va_end(args);
+        }
+
+        void WriteLine_VA(const utf8 * format, va_list args)
+        {
             vfprintf(stdout, format, args);
             puts("");
-            va_end(args);
         }
     }
 }
\ No newline at end of file
diff --git a/src/core/Console.hpp b/src/core/Console.hpp
index 4f8171235b..9b1d82f310 100644
--- a/src/core/Console.hpp
+++ b/src/core/Console.hpp
@@ -37,5 +37,6 @@ namespace Console
         void WriteFormat(const utf8 * format, ...);
         void WriteLine();
         void WriteLine(const utf8 * format, ...);
+        void WriteLine_VA(const utf8 * format, va_list args);
     }
 }
diff --git a/src/core/Guard.cpp b/src/core/Guard.cpp
index f88d871846..1e2e336dfc 100644
--- a/src/core/Guard.cpp
+++ b/src/core/Guard.cpp
@@ -15,34 +15,75 @@
 #pragma endregion
 
 #include <cassert>
+#include <stdarg.h>
 #include <stdio.h>
+#include <windows.h>
 
 #include "Console.hpp"
 #include "Diagnostics.hpp"
 #include "Guard.hpp"
 
+extern "C"
+{
+    #include "../openrct2.h"
+}
+
 namespace Guard
 {
-    void Assert(bool expression, const char * message)
+    void Assert(bool expression, const char * message, ...)
+    {
+        va_list args;
+        va_start(args, message);
+        Assert_VA(expression, message, args);
+        va_end(args);
+    }
+
+    void Assert_VA(bool expression, const char * message, va_list args)
     {
         if (expression) return;
 
         if (message != nullptr)
         {
-            Console::Error::WriteLine(message);
+            Console::Error::WriteLine("Assertion failed:");
+            Console::Error::WriteLine_VA(message, args);
         }
 
 #if DEBUG
         Debug::Break();
 #endif
+#if __WINDOWS__
+        char version[128];
+        openrct2_write_full_version_info(version, sizeof(version));
+
+        char buffer[512];
+        strcpy(buffer, "An assertion failed, please report this to the OpenRCT2 developers.\r\n\r\nVersion: ");
+        strcat(buffer, version);
+        strcat(buffer, "\r\n");
+        vsprintf((char *)strchr(buffer, 0), message, args);
+        int result = MessageBox(nullptr, buffer, OPENRCT2_NAME, MB_ABORTRETRYIGNORE | MB_ICONEXCLAMATION);
+        if (result == IDABORT)
+        {
+            // Force a crash that breakpad will handle allowing us to get a dump
+            *((void**)0) = 0;
+        }
+#else
         assert(false);
+#endif
     }
 
-    void Fail(const char * message)
+    void Fail(const char * message, ...)
+    {
+        va_list args;
+        va_start(args, message);
+        Fail_VA(message, args);
+        va_end(args);
+    }
+
+    void Fail_VA(const char * message, va_list args)
     {
         if (message != nullptr)
         {
-            Console::Error::WriteLine(message);
+            Console::Error::WriteLine_VA(message, args);
         }
 
 #if DEBUG
diff --git a/src/core/Guard.hpp b/src/core/Guard.hpp
index c4ba8cdefa..683514e4dd 100644
--- a/src/core/Guard.hpp
+++ b/src/core/Guard.hpp
@@ -16,23 +16,35 @@
 
 #pragma once
 
+#include <stdarg.h>
+
 /**
  * Utility methods for asserting function parameters.
  */
 namespace Guard
 {
-    void Assert(bool expression, const char * message = nullptr);
-    void Fail(const char * message = nullptr);
+    void Assert(bool expression, const char * message = nullptr, ...);
+    void Assert_VA(bool expression, const char * message, va_list args);
+    void Fail(const char * message = nullptr, ...);
+    void Fail_VA(const char * message, va_list args);
 
     template<typename T>
-    void ArgumentNotNull(T * argument, const char * message = nullptr)
+    void ArgumentNotNull(T * argument, const char * message = nullptr, ...)
     {
-        Assert(argument != nullptr, message);
+        va_list args;
+        va_start(args, message);
+        Assert_VA(argument != nullptr, message, args);
+        va_end(args);
     }
 
     template<typename T>
-    void ArgumentInRange(T argument, T min, T max, const char * message = nullptr)
+    void ArgumentInRange(T argument, T min, T max, const char * message = nullptr, ...)
     {
-        Assert(argument >= min && argument <= max, message);
+        va_list args;
+        va_start(args, message);
+        Assert(argument >= min && argument <= max, message, args);
+        va_end(args);
     }
 };
+
+#define GUARD_LINE "Location: %s:%d", __func__, __LINE__