From f28401554af8fe48994b0c08668f0c1408708fe1 Mon Sep 17 00:00:00 2001
From: Robert Maynard <robert.maynard@kitware.com>
Date: Thu, 9 Jun 2016 08:23:47 -0400
Subject: [PATCH] cmake-gui: Teach Qt5 where plugins are when launched through
 a symlink

When we are on OSX and we are launching cmake-gui from a symlink, the
application will fail to launch as it can't find the qt.conf file which
tells it what the name of the plugin folder is. We need to add this path
BEFORE the application is constructed as that is what triggers the
searching for the platform plugins
---
 Source/QtDialog/CMakeSetup.cxx | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/Source/QtDialog/CMakeSetup.cxx b/Source/QtDialog/CMakeSetup.cxx
index c3c14689a..c849d5292 100644
--- a/Source/QtDialog/CMakeSetup.cxx
+++ b/Source/QtDialog/CMakeSetup.cxx
@@ -19,6 +19,7 @@
 #include <QApplication>
 #include <QDir>
 #include <QLocale>
+#include <QString>
 #include <QTextCodec>
 #include <QTranslator>
 #include <cmsys/CommandLineArguments.hxx>
@@ -40,6 +41,7 @@ static const char* cmDocumentationOptions[][2] = { { 0, 0 } };
 
 #if defined(Q_OS_MAC)
 static int cmOSXInstall(std::string dir);
+static void cmAddPluginPath();
 #endif
 
 int main(int argc, char** argv)
@@ -81,6 +83,15 @@ int main(int argc, char** argv)
   }
 #endif
 
+// When we are on OSX and we are launching cmake-gui from a symlink, the
+// application will fail to launch as it can't find the qt.conf file which
+// tells it what the name of the plugin folder is. We need to add this path
+// BEFORE the application is constructed as that is what triggers the
+// searching for the platform plugins
+#if defined(Q_OS_MAC)
+  cmAddPluginPath();
+#endif
+
   QApplication app(argc, argv);
 
   setlocale(LC_NUMERIC, "C");
@@ -215,4 +226,27 @@ static int cmOSXInstall(std::string dir)
     ? 0
     : 1;
 }
+
+// Locate the PlugIns directory and add it to the QApplication library paths.
+// We need to resolve all symlinks so we have a known relative path between
+// MacOS/CMake and the PlugIns directory.
+//
+// Note we are using cmSystemTools since Qt can't provide the path to the
+// executable before the QApplication is created, and that is when plugin
+// searching occurs.
+static void cmAddPluginPath()
+{
+  std::string const& path = cmSystemTools::GetCMakeGUICommand();
+  if (path.empty()) {
+    return;
+  }
+  std::string const& realPath = cmSystemTools::GetRealPath(path);
+  QFileInfo appPath(QString::fromLocal8Bit(realPath.c_str()));
+  QDir pluginDir = appPath.dir();
+  bool const foundPluginDir = pluginDir.cd("../PlugIns");
+  if (foundPluginDir) {
+    QApplication::addLibraryPath(pluginDir.path());
+  }
+}
+
 #endif