Show relationships on top of other elements

gaphor/core/modeling/diagram.py

@@ -323,10 +323,15 @@ def iter_children(item):
                 yield child
                 yield from iter_children(child)
 
-        for root in self.ownedPresentation:
-            if not root.parent:
-                yield root
-                yield from iter_children(root)
+        def traverse_items() -> Iterable[Presentation]:
+            for root in self.ownedPresentation:
+                if not root.parent:
+                    yield root
+                    yield from iter_children(root)
+
+        yield from sorted(
+            traverse_items(), key=lambda e: int(isinstance(e, gaphas.Line))
+        )
 
     def get_parent(self, item: Presentation) -> Presentation | None:
         return item.parent

gaphor/core/modeling/element.py

@@ -5,7 +5,6 @@
 
 import logging
 import uuid
-from contextlib import contextmanager
 from typing import TYPE_CHECKING, Callable, Iterator, Protocol, TypeVar, overload
 
 from gaphor.core.modeling.event import ElementUpdated
@@ -200,10 +199,6 @@ def watcher(
     def handle(self, event: object) -> None:
         ...
 
-    @contextmanager
-    def block_events(self) -> Iterator[RepositoryProtocol]:
-        ...
-
 
 class EventWatcherProtocol(Protocol):
     def watch(self, path: str, handler: Handler | None = None) -> EventWatcherProtocol:

gaphor/core/modeling/presentation.py

@@ -23,14 +23,7 @@
 
 class Presentation(Matrices, Element, Generic[S]):
     """This presentation is used to link the behaviors of
-    `gaphor.core.modeling` and `gaphas.Item`.
-
-    Note that Presentations are not managed by the Element Factory.
-    Instead, Presentation objects are owned by Diagram. As a result they
-    do not emit ElementCreated and ElementDeleted events. Presentations
-    have their own create and delete events: ElementCreated and
-    ElementDeleted.
-    """
+    `gaphor.core.modeling` and `gaphas.Item`."""
 
     def __init__(self, diagram: Diagram, id: Id | None = None) -> None:
         super().__init__(id=id, model=diagram.model)

gaphor/core/modeling/tests/test_diagram.py

@@ -1,10 +1,7 @@
 import gaphas
 import pytest
 
-from gaphor.core.eventmanager import EventManager
-from gaphor.core.modeling import Diagram, ElementFactory, Presentation, StyleSheet
-from gaphor.core.modeling.elementdispatcher import ElementDispatcher
-from gaphor.UML.modelinglanguage import UMLModelingLanguage
+from gaphor.core.modeling import Diagram, Presentation, StyleSheet
 
 
 class Example(gaphas.Element, Presentation):
@@ -16,15 +13,18 @@ def unlink(self):
         super().unlink()
 
 
+class ExampleLine(gaphas.Line, Presentation):
+    def __init__(self, diagram, id):
+        super().__init__(connections=diagram.connections, diagram=diagram, id=id)
+
+    def unlink(self):
+        self.test_unlinked = True
+        super().unlink()
+
+
 @pytest.fixture
-def element_factory():
-    event_manager = EventManager()
-    element_dispatcher = ElementDispatcher(event_manager, UMLModelingLanguage())
-    element_factory = ElementFactory(event_manager, element_dispatcher)
-    yield element_factory
-    element_factory.shutdown()
-    element_dispatcher.shutdown()
-    event_manager.shutdown()
+def diagram(element_factory):
+    return element_factory.create(Diagram)
 
 
 def test_diagram_can_be_used_as_gtkview_model():
@@ -82,7 +82,6 @@ def request_update(self, items, removed_items) -> None:
 
 def test_remove_presentation_triggers_view(element_factory):
     diagram = element_factory.create(Diagram)
-    print(diagram.watcher())
     view = ViewMock()
     diagram.register_view(view)
 
@@ -93,3 +92,29 @@ def test_remove_presentation_triggers_view(element_factory):
     assert example.diagram is None
     assert example not in diagram.ownedPresentation
     assert example in view.removed_items
+
+
+def test_order_presentations_lines_are_last(diagram):
+    example_line = diagram.create(ExampleLine)
+    example = diagram.create(Example)
+
+    assert list(diagram.get_all_items()) == [example, example_line]
+
+
+def test_order_presentations_line_is_grouped(diagram):
+    example_line = diagram.create(ExampleLine)
+    example_1 = diagram.create(Example)
+    example_2 = diagram.create(Example)
+
+    example_line.parent = example_1
+
+    assert list(diagram.get_all_items()) == [example_1, example_2, example_line]
+
+
+def test_order_grouped_presentations(diagram):
+    example_1 = diagram.create(Example)
+    example_2 = diagram.create(Example)
+
+    example_1.parent = example_2
+
+    assert list(diagram.get_all_items()) == [example_2, example_1]

gaphor/services/tests/test_undo_presentation.py

@@ -51,7 +51,7 @@ def test_line_delete(diagram, undo_manager, event_manager):
 
 def test_line_orthogonal_property(diagram, undo_manager, event_manager):
     with Transaction(event_manager):
-        line = LinePresentation(diagram)
+        line = diagram.create(LinePresentation)
         line.insert_handle(0, Handle())
 
     with Transaction(event_manager):
@@ -70,7 +70,7 @@ def test_line_orthogonal_property(diagram, undo_manager, event_manager):
 
 def test_line_horizontal_property(diagram, undo_manager, event_manager):
     with Transaction(event_manager):
-        line = LinePresentation(diagram)
+        line = diagram.create(LinePresentation)
         line.insert_handle(0, Handle())
 
     with Transaction(event_manager):
@@ -99,7 +99,7 @@ def test_line_horizontal_property(diagram, undo_manager, event_manager):
 def test_matrix_operation(action, diagram, undo_manager, event_manager):
 
     with Transaction(event_manager):
-        line = LinePresentation(diagram)
+        line = diagram.create(LinePresentation)
         line.matrix.translate(10, 0)
 
     original = tuple(line.matrix)

gaphor/services/undomanager.py

@@ -265,14 +265,9 @@ def _action_executed(self, event=None):
         self.event_manager.handle(ActionEnabled("win.edit-redo", self.can_redo()))
         self.event_manager.handle(UndoManagerStateChanged(self))
 
-    def deep_lookup(self, id: str) -> Element:
+    def lookup(self, id: str) -> Element:
         element: Optional[Element] = self.element_factory.lookup(id)
         if not element:
-            for diagram in self.element_factory.select(Diagram):
-                presentation: Element
-                for presentation in diagram.ownedPresentation:
-                    if presentation.id == id:
-                        return presentation
             raise ValueError(f"Element with id {id} not found in model")
         return element
 
@@ -309,7 +304,7 @@ def undo_reversible_event(self, event: RevertibeEvent):
         element_id = event.element.id
 
         def b_undo_reversible_event():
-            element = self.deep_lookup(element_id)
+            element = self.lookup(element_id)
             event.revert(element)
 
         b_undo_reversible_event.__doc__ = (
@@ -325,7 +320,7 @@ def undo_create_element_event(self, event: ElementCreated):
         element_id = event.element.id
 
         def d_undo_create_event():
-            element = self.deep_lookup(element_id)
+            element = self.lookup(element_id)
             element.unlink()
 
         d_undo_create_event.__doc__ = f"Undo create element {event.element}."
@@ -348,7 +343,7 @@ def save_func(name, value):
             event.element.save(save_func)
 
             def b_undo_delete_event():
-                diagram: Diagram = self.deep_lookup(diagram_id)  # type: ignore[assignment]
+                diagram: Diagram = self.lookup(diagram_id)  # type: ignore[assignment]
                 element = diagram.create_as(element_type, element_id)
                 for name, ser in data.items():
                     for value in deserialize(ser, lambda ref: None):
@@ -374,7 +369,7 @@ def undo_attribute_change_event(self, event: AttributeUpdated):
         value = event.old_value
 
         def c_undo_attribute_change_event():
-            element = self.deep_lookup(element_id)
+            element = self.lookup(element_id)
             attribute._set(element, value)
 
         c_undo_attribute_change_event.__doc__ = (
@@ -393,8 +388,8 @@ def undo_association_set_event(self, event: AssociationSet):
         value_id = event.old_value and event.old_value.id
 
         def c_undo_association_set_event():
-            element = self.deep_lookup(element_id)
-            value = value_id and self.deep_lookup(value_id)
+            element = self.lookup(element_id)
+            value = value_id and self.lookup(value_id)
             association._set(element, value, from_opposite=True)
 
         c_undo_association_set_event.__doc__ = (
@@ -413,8 +408,8 @@ def undo_association_add_event(self, event: AssociationAdded):
         value_id = event.new_value.id
 
         def c_undo_association_add_event():
-            element = self.deep_lookup(element_id)
-            value = self.deep_lookup(value_id)
+            element = self.lookup(element_id)
+            value = self.lookup(value_id)
             association._del(element, value, from_opposite=True)
 
         c_undo_association_add_event.__doc__ = (
@@ -433,8 +428,8 @@ def undo_association_delete_event(self, event: AssociationDeleted):
         value_id = event.old_value.id
 
         def c_undo_association_delete_event():
-            element = self.deep_lookup(element_id)
-            value = self.deep_lookup(value_id)
+            element = self.lookup(element_id)
+            value = self.lookup(value_id)
             association._set(element, value, from_opposite=True)
 
         c_undo_association_delete_event.__doc__ = (