Save top-left handle position for elements

Otherwise the top-left handle position is always (0, 0),

Which results in unexpected visual changes in the model when loaded.

Fixes #1467.

gaphor/UML/actions/tests/test_action.py

@@ -9,3 +9,22 @@ def test_create_action(diagram, element_factory):
     item = diagram.create(ActionItem, subject=action)
 
     assert item.subject is action
+
+
+def test_load_action(element_factory, diagram, saver, loader):
+    action = diagram.create(ActionItem)
+
+    action.handles()[0].pos = (1, 2)
+    action.matrix.translate(10, 20)
+    action.width = 201
+    action.height = 202
+
+    dump = saver()
+    loader(dump)
+
+    new_action = next(element_factory.select(ActionItem))
+
+    assert tuple(new_action.handles()[0].pos) == (1, 2)
+    assert tuple(new_action.matrix) == (1.0, 0.0, 0.0, 1.0, 10, 20)
+    assert new_action.width == 201
+    assert new_action.height == 202

gaphor/diagram/presentation.py

@@ -151,12 +151,19 @@ class ElementPresentation(gaphas.Element, HandlePositionUpdate, Presentation[S])
 
     def save(self, save_func):
         save_func("matrix", tuple(self.matrix))
+        save_func("top-left", tuple(map(float, self._handles[0].pos)))
         save_func("width", self.width)
         save_func("height", self.height)
         super().save(save_func)
 
     def load(self, name, value):
-        if name == "width":
+        if name == "top-left":
+            pos = ast.literal_eval(value)
+            self._handles[0].pos = pos
+            # Also adjust bottom-right handle to keep width and height intact
+            self._handles[2].pos.x += pos[0]
+            self._handles[2].pos.y += pos[1]
+        elif name == "width":
             self.width = ast.literal_eval(value)
         elif name == "height":
             self.height = ast.literal_eval(value)

gaphor/diagram/tests/test_presentation.py

@@ -53,10 +53,11 @@ def test_element_saving(element_factory, diagram):
 
     p.save(save_func)
 
-    assert len(properties) == 5
+    assert len(properties) == 6
     assert properties["matrix"] == (1.0, 0.0, 0.0, 1.0, 0.0, 0.0)
     assert properties["width"] == 100.0
     assert properties["height"] == 50.0
+    assert properties["top-left"] == (0, 0)
     assert properties["subject"] is subject
     assert properties["diagram"] is diagram
 

test-models/simple-items.gaphor

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<gaphor xmlns="http://gaphor.sourceforge.net/model" version="3.0" gaphor-version="2.5.0">
+<gaphor xmlns="http://gaphor.sourceforge.net/model" version="3.0" gaphor-version="2.9.2">
 <Package id="DCE:658E43CC-3A1D-11DC-8B61-000D93868322">
 <name>
 <val>New model</val>
@@ -44,8 +44,11 @@
 </Line>
 <Box id="DCE:680E2142-3A1D-11DC-8B61-000D93868322">
 <matrix>
-<val>(1.0, 0.0, 0.0, 1.0, 215.0, 121.0)</val>
+<val>(1.0, 0.0, 0.0, 1.0, 214.0, 119.0)</val>
 </matrix>
+<top-left>
+<val>(0.0, 0.0)</val>
+</top-left>
 <width>
 <val>100.0</val>
 </width>
@@ -60,6 +63,9 @@
 <matrix>
 <val>(1.0, 0.0, 0.0, 1.0, 332.0, 137.0)</val>
 </matrix>
+<top-left>
+<val>(0.0, 0.0)</val>
+</top-left>
 <width>
 <val>100.0</val>
 </width>