From 59419824227148f6af39c4283c2efd73eca442e0 Mon Sep 17 00:00:00 2001
From: Alex Szpakowski <slime73@gmail.com>
Date: Tue, 27 Jun 2017 21:31:50 -0300
Subject: [PATCH] Error if a window isn't open when
 love.system.set/getClipboardText are called (resolves issue #1290).

--HG--
branch : minor
---
 src/modules/system/sdl/System.cpp  | 15 +++++++++++++++
 src/modules/system/sdl/System.h    |  2 ++
 src/modules/system/wrap_System.cpp |  6 ++++--
 3 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/src/modules/system/sdl/System.cpp b/src/modules/system/sdl/System.cpp
index 2dc89bd81..baeea6e17 100644
--- a/src/modules/system/sdl/System.cpp
+++ b/src/modules/system/sdl/System.cpp
@@ -20,6 +20,7 @@
 
 // LOVE
 #include "System.h"
+#include "window/Window.h"
 
 // SDL
 #include <SDL_clipboard.h>
@@ -46,13 +47,27 @@ int System::getProcessorCount() const
 	return SDL_GetCPUCount();
 }
 
+bool System::isWindowOpen() const
+{
+	auto window = Module::getInstance<window::Window>(M_WINDOW);
+	return window != nullptr && window->isOpen();
+}
+
 void System::setClipboardText(const std::string &text) const
 {
+	// SDL requires the video subsystem to be initialized and a window to be
+	// opened in order for clipboard text to work, on at least some platforms.
+	if (!isWindowOpen())
+		throw love::Exception("A window must be created in order for setClipboardText to function properly.");
+
 	SDL_SetClipboardText(text.c_str());
 }
 
 std::string System::getClipboardText() const
 {
+	if (!isWindowOpen())
+		throw love::Exception("A window must be created in order for getClipboardText to function properly.");
+
 	std::string text("");
 
 	char *ctext = SDL_GetClipboardText();
diff --git a/src/modules/system/sdl/System.h b/src/modules/system/sdl/System.h
index a75734875..06e6ca08f 100644
--- a/src/modules/system/sdl/System.h
+++ b/src/modules/system/sdl/System.h
@@ -54,6 +54,8 @@ public:
 
 private:
 
+	bool isWindowOpen() const;
+
 	static EnumMap<PowerState, SDL_PowerState, POWER_MAX_ENUM>::Entry powerEntries[];
 	static EnumMap<PowerState, SDL_PowerState, POWER_MAX_ENUM> powerStates;
 
diff --git a/src/modules/system/wrap_System.cpp b/src/modules/system/wrap_System.cpp
index 757192895..9e5d6ed76 100644
--- a/src/modules/system/wrap_System.cpp
+++ b/src/modules/system/wrap_System.cpp
@@ -44,13 +44,15 @@ int w_getProcessorCount(lua_State *L)
 int w_setClipboardText(lua_State *L)
 {
 	const char *text = luaL_checkstring(L, 1);
-	instance()->setClipboardText(text);
+	luax_catchexcept(L, [&]() { instance()->setClipboardText(text); });
 	return 0;
 }
 
 int w_getClipboardText(lua_State *L)
 {
-	luax_pushstring(L, instance()->getClipboardText());
+	std::string text;
+	luax_catchexcept(L, [&]() { text = instance()->getClipboardText(); });
+	luax_pushstring(L, text);
 	return 1;
 }