Bring app to front on macOS when run from source

Fixes #228

Author: davidfstr

RELEASE_NOTES.md

@@ -19,6 +19,10 @@ Release Notes ⋮
 * Testing improvements
     * Increased determinism and speed of tests that perform downloads.
 
+* Development improvements
+    * Manually bring app to front on macOS when run from source,
+      to workaround a wxPython 4.2.3 bug.
+
 ### v2.0.0 (September 26, 2025)
 
 Crystal 2.0 is a huge release with many new features and all-new tutorials!

src/crystal/main.py

@@ -650,6 +650,7 @@ async def _did_launch(
     from crystal.server import _DEFAULT_SERVER_HOST, _DEFAULT_SERVER_PORT
     from crystal.util.ports import is_port_in_use_error
     from crystal.util.test_mode import tests_are_running
+    from crystal.util.xos import is_mac_os
 
     # If MacOpenFile queued a project to be opened, open it
     global _project_path_to_open_soon
@@ -661,6 +662,13 @@ async def _did_launch(
     if parsed_args.project_filepath is not None and filepath is None:
         filepath = parsed_args.project_filepath  # reinterpret
 
+    # wxPython 4.2.3: Workaround bug where the launched application is not
+    # brought to the front on macOS when run outside of an .app bundle.
+    # For more info: https://github.com/wxWidgets/Phoenix/issues/2499
+    if is_mac_os() and getattr(sys, 'frozen', None) != 'macosx_app':
+        from crystal.util.bring_app_to_front import bring_app_to_front
+        bring_app_to_front()
+    
     # Open/create a project
     project: Project | None = None
     window: MainWindow | None = None

src/crystal/util/bring_app_to_front.py

@@ -0,0 +1,51 @@
+import sys
+
+
+def bring_app_to_front() -> None:
+    """Brings the current application to the front on macOS."""
+    if sys.platform != 'darwin':
+        raise ValueError('Not supported on this OS')
+    
+    try:
+        import ctypes
+        import ctypes.util
+        
+        # Load the AppKit framework
+        appkit_path = ctypes.util.find_library('AppKit')
+        if appkit_path is None:
+            print('Warning: Could not find AppKit framework', file=sys.stderr)
+            return
+        objc_path = ctypes.util.find_library('objc')
+        if objc_path is None:
+            print('Warning: Could not find objc library', file=sys.stderr)
+            return
+        
+        appkit = ctypes.cdll.LoadLibrary(appkit_path)
+        objc = ctypes.cdll.LoadLibrary(objc_path)
+        
+        # Define objc_getClass to lookup Objective-C classes
+        objc.objc_getClass.restype = ctypes.c_void_p
+        objc.objc_getClass.argtypes = [ctypes.c_char_p]
+        
+        # Define sel_registerName to lookup Objective-C selectors
+        objc.sel_registerName.restype = ctypes.c_void_p
+        objc.sel_registerName.argtypes = [ctypes.c_char_p]
+            
+        # Define objc_msgSend for calling Objective-C methods
+        objc_msgSend = objc.objc_msgSend
+        objc_msgSend.restype = ctypes.c_void_p
+        objc_msgSend.argtypes = [ctypes.c_void_p, ctypes.c_void_p]
+        
+        # Get the shared application instance
+        NSApplication = objc.objc_getClass(b'NSApplication')
+        sharedApplication = objc.sel_registerName(b'sharedApplication')
+        app = objc_msgSend(NSApplication, sharedApplication)
+        
+        # Activate the application, ignoring other apps
+        activateIgnoringOtherApps = objc.sel_registerName(b'activateIgnoringOtherApps:')
+        objc_msgSend_bool = objc.objc_msgSend
+        objc_msgSend_bool.argtypes = [ctypes.c_void_p, ctypes.c_void_p, ctypes.c_bool]
+        objc_msgSend_bool(app, activateIgnoringOtherApps, True)
+        
+    except Exception as e:
+        print(f'Warning: Failed to bring application to front: {e}', file=sys.stderr)