-Item stffix is stripped from item names

gaphor/core/modeling/diagram.py

@@ -15,6 +15,7 @@ import gaphas
 from gaphor.core.modeling.coremodel import PackageableElement
 from gaphor.core.modeling.element import Id, RepositoryProtocol
 from gaphor.core.modeling.event import DiagramItemCreated
+from gaphor.core.modeling.presentation import Presentation
 from gaphor.core.modeling.stylesheet import StyleSheet
 from gaphor.core.styling import FontStyle, Style, StyleNode, TextAlign
 
@@ -69,12 +70,21 @@ class DrawContext:
     dropzone: bool
 
 
+# From https://www.python.org/dev/peps/pep-0616/
+def removesuffix(self: str, suffix: str, /) -> str:
+    # suffix='' should not call self[:-0].
+    if suffix and self.endswith(suffix):
+        return self[: -len(suffix)]
+    else:
+        return self[:]
+
+
 class StyledDiagram:
     def __init__(self, diagram: Diagram, view: Optional[gaphas.View] = None):
         self.diagram = diagram
         self.view = view
 
-    def local_name(self) -> str:
+    def name(self) -> str:
         return "diagram"
 
     def parent(self):
@@ -99,13 +109,14 @@ class StyledItem:
     pseudo-classes for the item (focus, hover, etc.)
     """
 
-    def __init__(self, item: gaphas.Item, view: Optional[gaphas.View] = None):
+    def __init__(self, item: Presentation, view: Optional[gaphas.View] = None):
+        assert item.canvas
         self.item = item
         self.canvas = item.canvas
         self.view = view
 
-    def local_name(self) -> str:
-        return type(self.item).__name__.lower()
+    def name(self) -> str:
+        return removesuffix(type(self.item).__name__, "Item").lower()
 
     def parent(self) -> Union[StyledItem, StyledDiagram]:
         parent = self.canvas.get_parent(self.item)
@@ -254,7 +265,9 @@ class Diagram(PackageableElement):
         return self.create_as(type, str(uuid.uuid1()), parent, subject)
 
     def create_as(self, type, id, parent=None, subject=None):
-        if not (type and issubclass(type, gaphas.Item)):
+        if not (
+            type and issubclass(type, gaphas.Item) and issubclass(type, Presentation)
+        ):
             raise TypeError(
                 f"Type {type} can not be added to a diagram as it is not a diagram item"
             )

gaphor/core/modeling/tests/test_diagram_style.py

@@ -0,0 +1,47 @@
+import gaphas
+import pytest
+
+from gaphor.core.eventmanager import EventManager
+from gaphor.core.modeling import ElementFactory, Presentation
+from gaphor.core.modeling.diagram import Diagram, StyledDiagram, StyledItem
+
+
+@pytest.fixture
+def event_manager():
+    return EventManager()
+
+
+@pytest.fixture
+def element_factory(event_manager):
+    return ElementFactory(event_manager)
+
+
+@pytest.fixture
+def diagram(element_factory):
+    diagram = element_factory.create(Diagram)
+    yield diagram
+    diagram.unlink()
+
+
+class DemoItem(Presentation, gaphas.Item):
+    pass
+
+
+def test_name_does_not_have_item_suffix(diagram):
+    item = diagram.create(DemoItem)
+    node = StyledItem(item)
+
+    assert node.name() == "demo"
+
+
+def test_diagram_is_parent_of_item(diagram):
+    item = diagram.create(DemoItem)
+    node = StyledItem(item)
+
+    assert node.parent().name() == "diagram"
+
+
+def test_diagram_has_no_parent(diagram):
+    node = StyledDiagram(diagram)
+
+    assert node.parent() is None

gaphor/core/styling/__init__.py

@@ -30,7 +30,7 @@ from gaphor.core.styling.selectors import compile_selector_list
 
 
 class StyleNode(Protocol):
-    def local_name(self) -> str:
+    def name(self) -> str:
         ...
 
     def parent(self) -> Optional[StyleNode]:

gaphor/core/styling/selectors.py

@@ -43,8 +43,8 @@ def compile_compound_selector(selector: parser.CompoundSelector):
 
 
 @compile_node.register
-def compile_local_name_selector(selector: parser.LocalNameSelector):
-    return lambda el: el.local_name() == selector.lower_local_name
+def compile_name_selector(selector: parser.LocalNameSelector):
+    return lambda el: el.name() == selector.lower_local_name
 
 
 def ancestors(el):

gaphor/core/styling/tests/test_selector.py

@@ -4,8 +4,8 @@ from gaphor.core.styling import parse_style_sheet
 
 
 class Node:
-    def __init__(self, local_name, parent=None, children=None, attributes={}, state=()):
-        self._local_name = local_name
+    def __init__(self, name, parent=None, children=None, attributes={}, state=()):
+        self._name = name
         self._parent = parent
         self._children = children or []
         self._attributes = attributes
@@ -16,8 +16,8 @@ class Node:
         for c in self._children:
             c._parent = self
 
-    def local_name(self):
-        return self._local_name
+    def name(self):
+        return self._name
 
     def parent(self):
         return self._parent
@@ -36,8 +36,8 @@ def test_node_test_object_parent_child():
     c = Node("child")
     p = Node("parent", children=[c])
 
-    assert c.local_name() == "child"
-    assert p.local_name() == "parent"
+    assert c.name() == "child"
+    assert p.name() == "parent"
     assert c.parent() is p
     assert c in p.children()
 
@@ -46,8 +46,8 @@ def test_node_test_object_child_parent():
     p = Node("parent")
     c = Node("child", parent=p)
 
-    assert c.local_name() == "child"
-    assert p.local_name() == "parent"
+    assert c.name() == "child"
+    assert p.name() == "parent"
     assert c.parent() is p
     assert c in p.children()