Fix how we deal with component IDs for linked components

CHANGES.md

@@ -9,6 +9,9 @@ v0.11.0 (unreleased)
 v0.10.2 (unreleased)
 --------------------
 
+* Fixed a bug that caused components that were linked to then disappear from
+  drop-down lists of available components in new viewers. [#1270]
+
 * Fixed a bug that caused Data.find_component_id to return incorrect results
   when string components were present in the data. [#1269]
 

glue/core/data.py

@@ -391,7 +391,8 @@ def add_component(self, component, label, hidden=False):
 
         if isinstance(label, ComponentID):
             component_id = label
-            component_id.parent = self
+            if component_id.parent is None:
+                component_id.parent = self
         else:
             component_id = ComponentID(label, hidden=hidden, parent=self)
 
@@ -471,7 +472,7 @@ def visible_components(self):
         :rtype: list
         """
         return [cid for cid, comp in self._components.items()
-                if not cid.hidden and not comp.hidden]
+                if not cid.hidden and not comp.hidden and cid.parent is self]
 
     @property
     def coordinate_components(self):
@@ -931,7 +932,7 @@ def update_values_from_data(self, data):
             if cname in new_labels - old_labels:
                 cid = data.find_component_id(cname)
                 comp_new = data.get_component(cname)
-                self.add_component(comp_new, cid)
+                self.add_component(comp_new, cid.label)
 
         # Update data label
         self.label = data.label

glue/core/link_manager.py

@@ -196,9 +196,6 @@ def _add_deriveable_components(self, data):
         for cid, link in six.iteritems(links):
             d = DerivedComponent(data, link)
             if cid not in data.components:
-                # Need to hide component since we don't want to show components
-                # that are auto-generated in datasets by default.
-                cid.hidden = True
                 data.add_component(d, cid)
 
     @property

glue/core/tests/test_data.py

@@ -583,7 +583,8 @@ def test_update_values_from_data():
     assert d1a not in d1.components
     assert d1b in d1.components
     assert d2b not in d1.components
-    assert d2c in d1.components
+    assert d2c not in d1.components
+    assert [cid.label for cid in d1.visible_components] == ['b', 'c']
     assert d1.shape == (4,)
 
 
@@ -624,8 +625,7 @@ def test_update_values_from_data_order():
 
     d2.update_values_from_data(d1)
 
-    assert d2.visible_components == [d2.id['j'], d2.id['a'], d1.id['c'],
-                                     d1.id['b'], d1.id['f']]
+    assert [cid.label for cid in d2.visible_components] == ['j', 'a', 'c', 'b', 'f']
 
 
 def test_find_component_id_with_cid():
@@ -639,3 +639,39 @@ def test_find_component_id_with_cid():
 
     assert d1.find_component_id(d1.id['a']) is d1.id['a']
     assert d1.find_component_id(d1.id['b']) is d1.id['b']
+
+
+def test_linked_component_visible():
+
+    # Regression test for a bug that caused components to become hidden once
+    # they were linked with another component.
+
+    from ..link_helpers import LinkSame
+    from ..data_collection import DataCollection
+
+    d1 = Data(x=[1], y=[2])
+    d2 = Data(w=[3], v=[4])
+
+    assert not d1.id['x'].hidden
+    assert not d2.id['w'].hidden
+
+    dc = DataCollection([d1, d2])
+    dc.add_link(LinkSame(d1.id['x'], d2.id['w']))
+
+    assert d1.id['x'] is d2.id['x']
+    assert d1.id['w'] is d2.id['w']
+
+    assert not d1.id['x'].hidden
+    assert not d2.id['w'].hidden
+
+    assert not d1.id['w'].hidden
+    assert not d2.id['x'].hidden
+
+    assert d1.id['x'].parent is d1
+    assert d1.id['y'].parent is d1
+
+    assert d2.id['w'].parent is d2
+    assert d2.id['v'].parent is d2
+
+    assert d1.visible_components == [d1.id['x'], d1.id['y']]
+    assert d2.visible_components == [d2.id['v'], d2.id['w']]