Add a warning when trying to access theme items too early

scene/gui/control.cpp

@@ -2424,6 +2424,10 @@ StringName Control::get_theme_type_variation() const {
 /// Theme property lookup.
 
 Ref<Texture2D> Control::get_theme_icon(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!data.initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == data.theme_type_variation) {
 		const Ref<Texture2D> *tex = data.theme_icon_override.getptr(p_name);
 		if (tex) {
@@ -2443,6 +2447,10 @@ Ref<Texture2D> Control::get_theme_icon(const StringName &p_name, const StringNam
 }
 
 Ref<StyleBox> Control::get_theme_stylebox(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!data.initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == data.theme_type_variation) {
 		const Ref<StyleBox> *style = data.theme_style_override.getptr(p_name);
 		if (style) {
@@ -2462,6 +2470,10 @@ Ref<StyleBox> Control::get_theme_stylebox(const StringName &p_name, const String
 }
 
 Ref<Font> Control::get_theme_font(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!data.initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == data.theme_type_variation) {
 		const Ref<Font> *font = data.theme_font_override.getptr(p_name);
 		if (font) {
@@ -2481,6 +2493,10 @@ Ref<Font> Control::get_theme_font(const StringName &p_name, const StringName &p_
 }
 
 int Control::get_theme_font_size(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!data.initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == data.theme_type_variation) {
 		const int *font_size = data.theme_font_size_override.getptr(p_name);
 		if (font_size && (*font_size) > 0) {
@@ -2500,6 +2516,10 @@ int Control::get_theme_font_size(const StringName &p_name, const StringName &p_t
 }
 
 Color Control::get_theme_color(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!data.initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == data.theme_type_variation) {
 		const Color *color = data.theme_color_override.getptr(p_name);
 		if (color) {
@@ -2519,6 +2539,10 @@ Color Control::get_theme_color(const StringName &p_name, const StringName &p_the
 }
 
 int Control::get_theme_constant(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!data.initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == data.theme_type_variation) {
 		const int *constant = data.theme_constant_override.getptr(p_name);
 		if (constant) {
@@ -2538,6 +2562,10 @@ int Control::get_theme_constant(const StringName &p_name, const StringName &p_th
 }
 
 bool Control::has_theme_icon(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!data.initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == data.theme_type_variation) {
 		if (has_theme_icon_override(p_name)) {
 			return true;
@@ -2550,6 +2578,10 @@ bool Control::has_theme_icon(const StringName &p_name, const StringName &p_theme
 }
 
 bool Control::has_theme_stylebox(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!data.initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == data.theme_type_variation) {
 		if (has_theme_stylebox_override(p_name)) {
 			return true;
@@ -2562,6 +2594,10 @@ bool Control::has_theme_stylebox(const StringName &p_name, const StringName &p_t
 }
 
 bool Control::has_theme_font(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!data.initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == data.theme_type_variation) {
 		if (has_theme_font_override(p_name)) {
 			return true;
@@ -2574,6 +2610,10 @@ bool Control::has_theme_font(const StringName &p_name, const StringName &p_theme
 }
 
 bool Control::has_theme_font_size(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!data.initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == data.theme_type_variation) {
 		if (has_theme_font_size_override(p_name)) {
 			return true;
@@ -2586,6 +2626,10 @@ bool Control::has_theme_font_size(const StringName &p_name, const StringName &p_
 }
 
 bool Control::has_theme_color(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!data.initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == data.theme_type_variation) {
 		if (has_theme_color_override(p_name)) {
 			return true;
@@ -2598,6 +2642,10 @@ bool Control::has_theme_color(const StringName &p_name, const StringName &p_them
 }
 
 bool Control::has_theme_constant(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!data.initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == data.theme_type_variation) {
 		if (has_theme_constant_override(p_name)) {
 			return true;
@@ -2894,6 +2942,8 @@ Control *Control::make_custom_tooltip(const String &p_text) const {
 void Control::_notification(int p_notification) {
 	switch (p_notification) {
 		case NOTIFICATION_POSTINITIALIZE: {
+			data.initialized = true;
+
 			_invalidate_theme_cache();
 			_update_theme_item_cache();
 		} break;

scene/gui/control.h

@@ -161,6 +161,8 @@ private:
 
 	// This Data struct is to avoid namespace pollution in derived classes.
 	struct Data {
+		bool initialized = false;
+
 		// Global relations.
 
 		List<Control *>::Element *RI = nullptr;

scene/main/window.cpp

@@ -1073,6 +1073,8 @@ Viewport *Window::get_embedder() const {
 void Window::_notification(int p_what) {
 	switch (p_what) {
 		case NOTIFICATION_POSTINITIALIZE: {
+			initialized = true;
+
 			_invalidate_theme_cache();
 			_update_theme_item_cache();
 		} break;
@@ -1754,6 +1756,10 @@ StringName Window::get_theme_type_variation() const {
 /// Theme property lookup.
 
 Ref<Texture2D> Window::get_theme_icon(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == theme_type_variation) {
 		const Ref<Texture2D> *tex = theme_icon_override.getptr(p_name);
 		if (tex) {
@@ -1773,6 +1779,10 @@ Ref<Texture2D> Window::get_theme_icon(const StringName &p_name, const StringName
 }
 
 Ref<StyleBox> Window::get_theme_stylebox(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == theme_type_variation) {
 		const Ref<StyleBox> *style = theme_style_override.getptr(p_name);
 		if (style) {
@@ -1792,6 +1802,10 @@ Ref<StyleBox> Window::get_theme_stylebox(const StringName &p_name, const StringN
 }
 
 Ref<Font> Window::get_theme_font(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == theme_type_variation) {
 		const Ref<Font> *font = theme_font_override.getptr(p_name);
 		if (font) {
@@ -1811,6 +1825,10 @@ Ref<Font> Window::get_theme_font(const StringName &p_name, const StringName &p_t
 }
 
 int Window::get_theme_font_size(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == theme_type_variation) {
 		const int *font_size = theme_font_size_override.getptr(p_name);
 		if (font_size && (*font_size) > 0) {
@@ -1830,6 +1848,10 @@ int Window::get_theme_font_size(const StringName &p_name, const StringName &p_th
 }
 
 Color Window::get_theme_color(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == theme_type_variation) {
 		const Color *color = theme_color_override.getptr(p_name);
 		if (color) {
@@ -1849,6 +1871,10 @@ Color Window::get_theme_color(const StringName &p_name, const StringName &p_them
 }
 
 int Window::get_theme_constant(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == theme_type_variation) {
 		const int *constant = theme_constant_override.getptr(p_name);
 		if (constant) {
@@ -1868,6 +1894,10 @@ int Window::get_theme_constant(const StringName &p_name, const StringName &p_the
 }
 
 bool Window::has_theme_icon(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == theme_type_variation) {
 		if (has_theme_icon_override(p_name)) {
 			return true;
@@ -1880,6 +1910,10 @@ bool Window::has_theme_icon(const StringName &p_name, const StringName &p_theme_
 }
 
 bool Window::has_theme_stylebox(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == theme_type_variation) {
 		if (has_theme_stylebox_override(p_name)) {
 			return true;
@@ -1892,6 +1926,10 @@ bool Window::has_theme_stylebox(const StringName &p_name, const StringName &p_th
 }
 
 bool Window::has_theme_font(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == theme_type_variation) {
 		if (has_theme_font_override(p_name)) {
 			return true;
@@ -1904,6 +1942,10 @@ bool Window::has_theme_font(const StringName &p_name, const StringName &p_theme_
 }
 
 bool Window::has_theme_font_size(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == theme_type_variation) {
 		if (has_theme_font_size_override(p_name)) {
 			return true;
@@ -1916,6 +1958,10 @@ bool Window::has_theme_font_size(const StringName &p_name, const StringName &p_t
 }
 
 bool Window::has_theme_color(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == theme_type_variation) {
 		if (has_theme_color_override(p_name)) {
 			return true;
@@ -1928,6 +1974,10 @@ bool Window::has_theme_color(const StringName &p_name, const StringName &p_theme
 }
 
 bool Window::has_theme_constant(const StringName &p_name, const StringName &p_theme_type) const {
+	if (!initialized) {
+		WARN_PRINT_ONCE("Attempting to access theme items too early; prefer NOTIFICATION_POSTINITIALIZE and NOTIFICATION_THEME_CHANGED");
+	}
+
 	if (p_theme_type == StringName() || p_theme_type == get_class_name() || p_theme_type == theme_type_variation) {
 		if (has_theme_constant_override(p_name)) {
 			return true;

scene/main/window.h

@@ -97,6 +97,7 @@ public:
 
 private:
 	DisplayServer::WindowID window_id = DisplayServer::INVALID_WINDOW_ID;
+	bool initialized = false;
 
 	String title;
 	mutable int current_screen = 0;