Allow labels on different layers when label_layer=None

gdsfactory/add_labels.py

@@ -259,18 +259,18 @@ def add_siepic_labels(
 
 def add_labels_to_ports(
     component: Component,
-    label_layer: LayerSpec = "TEXT",
+    label_layer: LayerSpec | None = "TEXT",
     port_type: str | None = None,
     **kwargs,
 ) -> Component:
     """Add labels to component ports.
 
     Args:
         component: to add labels.
-        label_layer: layer spec for the label.
+        label_layer: layer spec for the label. None will use the port layer.
         port_type: to select ports.
 
-    keyword Args:
+    Keyword Args:
         layer: select ports with GDS layer.
         prefix: select ports with prefix in port name.
         suffix: select ports with port name suffix.
@@ -282,7 +282,11 @@ def add_labels_to_ports(
     """
     ports = component.get_ports_list(port_type=port_type, **kwargs)
     for port in ports:
-        component.add_label(text=port.name, position=port.center, layer=label_layer)
+        component.add_label(
+            text=port.name,
+            position=port.center,
+            layer=label_layer if label_layer else port.layer,
+        )
 
     return component