Provide connection properties directly to callback

This avoids stale data in the callback when the connection
is reconnected. Reconnect may use a different port.

gaphas/connections.py

@@ -28,7 +28,7 @@ class Connection(NamedTuple):
     connected: Item
     port: Port
     constraint: Constraint
-    callback: Callable[[], None]
+    callback: Callable[[Item, Handle, Item, Port], None]
 
 
 class ConnectionError(Exception):
@@ -91,7 +91,7 @@ class Connections:
         connected: Item,
         port: Port | None,
         constraint: Constraint | None = None,
-        callback: Callable[[], None] | None = None,
+        callback: Callable[[Item, Handle, Item, Port], None] | None = None,
     ) -> None:
         """Create a connection between two items. The connection is registered
         and the constraint is added to the constraint solver.
@@ -137,7 +137,7 @@ class Connections:
         connected: Item,
         port: Port,
         constraint: Constraint,
-        callback: Callable[[], None],
+        callback: Callable[[Item, Handle, Item, Port], None],
     ) -> None:
         """Perform the real disconnect."""
         # Same arguments as connect_item, makes reverser easy
@@ -145,7 +145,7 @@ class Connections:
             self._solver.remove_constraint(constraint)
 
         if callback:
-            callback()
+            callback(item, handle, connected, port)
 
         self._connections.delete(item, handle, connected, port, constraint, callback)
 

gaphas/connector.py

@@ -80,7 +80,9 @@ class ItemConnector:
         self.connect_handle(sink)
 
     def connect_handle(
-        self, sink: ConnectionSinkType, callback: Optional[Callable[[], None]] = None
+        self,
+        sink: ConnectionSinkType,
+        callback: Optional[Callable[[Item, Handle, Item, Port], None]] = None,
     ) -> None:
         """Create constraint between handle of a line and port of connectable
         item.

tests/test_canvas.py

@@ -70,7 +70,7 @@ def test_disconnect_item_with_callback():
 
     events = []
 
-    def callback():
+    def callback(*args):
         events.append("called")
 
     c.connections.connect_item(
@@ -118,7 +118,7 @@ def test_disconnect_item_by_deleting_element():
 
     events = []
 
-    def callback():
+    def callback(*args):
         events.append("called")
 
     c.connections.connect_item(

tests/test_segment.py

@@ -1,9 +1,10 @@
 """Test segment aspects for items."""
 import pytest
 
+from gaphas.connector import ItemConnectionSink, ItemConnector
 from gaphas.handlemove import HandleMove
-from gaphas.item import Element
-from gaphas.segment import Line, Segment
+from gaphas.item import Element, Line
+from gaphas.segment import Segment
 
 
 def test_segment_fails_for_element(canvas, connections):
@@ -327,3 +328,23 @@ def test_merge_orthogonal_line(canvas, connections):
 
     with pytest.raises(ValueError):
         Segment(line, canvas).merge_segment(1)
+
+
+def callback(_item, _handle, connected, port):
+    connected.ports().index(port)
+
+
+def test_update_callback_on_reconnect(canvas, connections):
+    line = Line(connections)
+    attached = Line(connections)
+    segment = Segment(line, canvas)
+
+    sink = ItemConnectionSink(line)
+    connector = ItemConnector(attached, attached.handles()[0], connections)
+
+    segment.split_segment(0)
+    connector.glue(sink)
+    connector.connect_handle(sink, callback)
+    segment.merge_segment(0)
+
+    connector.disconnect()