Restart the application bundle instead of the underlying executable when crashing on macOS (#3268)

On macOS, programs are contained in ".app" application bundles. When chatterino restarts on a crash, it currently just looks for the executable path obtained via QApplication::applicationFilePath() and starts that again, which for macOS is the underlying unix executable inside of the application bundle. Unfortunately, for macOS those 2 are absolutely different, resulting in i.e. a second chatterino icon being added to the dock, due to the OS not recognizing that it is the same application.

src/RunGui.cpp

@@ -28,6 +28,10 @@
 #    include <QBreakpadHandler.h>
 #endif
 
+#ifdef Q_OS_MAC
+#    include "corefoundation/CFBundle.h"
+#endif
+
 namespace chatterino {
 namespace {
     void installCustomPalette()
@@ -122,8 +126,29 @@ namespace {
             std::chrono::steady_clock::now() - signalsInitTime > 30s)
         {
             QProcess proc;
+
+#ifdef Q_OS_MAC
+            // On macOS, programs are bundled into ".app" Application bundles,
+            // when restarting chatterino that bundle should be opened with the "open"
+            // terminal command instead of directly starting the underlying executable,
+            // as those are 2 different things for the OS and i.e. do not use
+            // the same dock icon (resulting in a second chatterino icon on restarting)
+            CFURLRef appUrlRef = CFBundleCopyBundleURL(CFBundleGetMainBundle());
+            CFStringRef macPath =
+                CFURLCopyFileSystemPath(appUrlRef, kCFURLPOSIXPathStyle);
+            const char *pathPtr =
+                CFStringGetCStringPtr(macPath, CFStringGetSystemEncoding());
+
+            proc.setProgram("open");
+            proc.setArguments({pathPtr, "--args", "--crash-recovery"});
+
+            CFRelease(appUrlRef);
+            CFRelease(macPath);
+#else
             proc.setProgram(QApplication::applicationFilePath());
             proc.setArguments({"--crash-recovery"});
+#endif
+
             proc.startDetached();
         }