Add an option to hide the window title bar on macOS

Fixes #84

kitty/cocoa_window.m

@@ -15,9 +15,13 @@
 
 PyObject*
 cocoa_hide_titlebar(PyObject UNUSED *self, PyObject *window_id) {
-    NSView *native_view = (NSView*)PyLong_AsVoidPtr(window_id);
-    NSWindow* window = [native_view window];
-    [window setStyleMask:
-        [window styleMask] & ~NSWindowStyleMaskTitled];
+    NSWindow *window = (NSWindow*)PyLong_AsVoidPtr(window_id);
+    
+    @try {
+        [window setStyleMask:
+            [window styleMask] & ~NSWindowStyleMaskTitled];
+    } @catch (NSException *e) {
+        return PyErr_Format(PyExc_ValueError, "Failed to set style mask: %s: %s", [[e name] UTF8String], [[e reason] UTF8String]);
+    }
     Py_RETURN_NONE;
 }

kitty/config.py

@@ -173,6 +173,7 @@ type_map = {
     'initial_window_width': int,
     'initial_window_height': int,
     'use_system_wcwidth': to_bool,
+    'macos_hide_titlebar': to_bool,
 }
 
 for name in (

kitty/glfw.c

@@ -377,7 +377,7 @@ request_window_attention(Window *self) {
 }
 #endif
 
-#ifdef glfwGetCocoaWindow
+#ifdef __APPLE__
 static PyObject*
 cocoa_window_id(Window *self) {
     void *wid = glfwGetCocoaWindow(self->window);
@@ -400,7 +400,7 @@ static PyMethodDef methods[] = {
 #ifdef glfwRequestWindowAttention
     MND(request_window_attention, METH_NOARGS),
 #endif
-#ifdef cocoa_window_id
+#ifdef __APPLE__
     MND(cocoa_window_id, METH_NOARGS),
 #endif
     MND(set_should_close, METH_VARARGS),

kitty/kitty.conf

@@ -237,3 +237,9 @@ map ctrl+shift+backspace restore_font_size
 # For example:
 # 
 # symbol_map U+E0A0-U+E0A2,U+E0B0-U+E0B3 PowerlineSymbols
+
+
+# OS specific tweaks
+
+# Hide the kitty window's title bar on macOS.
+macos_hide_titlebar no

kitty/main.py

@@ -191,7 +191,11 @@ def run_app(opts, args):
     window = Window(viewport_size.width, viewport_size.height, args.cls)
     window.set_title(appname)
     window.make_context_current()
-    if not isosx:
+    if isosx:
+        if opts.macos_hide_titlebar:
+            from .fast_data_types import cocoa_hide_titlebar
+            cocoa_hide_titlebar(window.cocoa_window_id())
+    else:
         with open(logo_data_file, 'rb') as f:
             window.set_icon(f.read(), 256, 256)
     viewport_size.width, viewport_size.height = window.get_framebuffer_size()