fix: release the type registry when a model version is selected

code/+openminds/+introspection/+internal/@MetaTypeRegistry/MetaTypeRegistry.m

@@ -47,6 +47,29 @@
         % getSingleton - Method for retrieving singleton object
         % Defined in separate file in class folder
         singletonObject = getSingleton(options)
+
+        function notifyModelVersionChanged()
+        % notifyModelVersionChanged - Release the registry for a change of model version
+        %
+        %   Syntax:
+        %       openminds.introspection.internal.MetaTypeRegistry.notifyModelVersionChanged()
+        %
+        %   The registry holds enumeration values (openminds.enum.Types)
+        %   of the model version it was built for, and a registry left in
+        %   place across a version switch keeps the previous version's
+        %   types in memory. This method deletes the registry; it is
+        %   rebuilt on its next use. It is called from
+        %   openminds.selectModelVersion.
+        %
+        %   See also openminds.selectModelVersion
+
+            singletonObject = getappdata(0, ...
+                openminds.introspection.internal.MetaTypeRegistry.SINGLETON_NAME);
+
+            if ~isempty(singletonObject) && isvalid(singletonObject)
+                delete(singletonObject)
+            end
+        end
     end
 
     methods (Access = private)

code/+openminds/selectModelVersion.m

@@ -73,6 +73,13 @@ function selectModelVersion(versionNumber)
     % enumerations and the controlled term base class generated for it.
     addpath(genpath( fullfile(generatedFolder, versionAsString) ))
 
+    % MATLAB reads the classes of the selected version only once nothing
+    % holds those of the previous one. The type registry holds enumeration
+    % values of the version it was built for, so it is released here: before
+    % the pause that lets the reload happen, and before the instance library
+    % resolves types against the reloaded classes. Its next use rebuilds it.
+    openminds.introspection.internal.MetaTypeRegistry.notifyModelVersionChanged()
+
     % Add a second pause for changes to take effect.
     pause(1) % Ad hoc value. Usually at least 0.3 - 0.4 seconds is necessary
 

tools/tests/unitTests/InstanceLibraryIntegrationTest.m

@@ -90,15 +90,19 @@ function testLibraryVersionFollowsTheModelVersion(testCase)
                 'The instance library holds no instances for this version.')
 
             % Check that the instances were read from the v3.0 folder, not
-            % merely labelled v3.0. Whether every instance then resolves to
-            % a type depends on the model classes having been reloaded,
-            % which MATLAB cannot do while objects of those classes exist
-            % in the session, so that is not checked here.
+            % merely labelled v3.0.
             readFromVersion = contains(library.InstanceTable.Filepath, ...
                 fullfile(filesep, "v3.0", filesep));
 
             testCase.verifyTrue(all(readFromVersion), ...
                 'The library must read the instances of the selected version.')
+
+            % The instances must also be typed against that version's
+            % classes. Selecting a version releases the type registry, so
+            % the classes reload and every instance resolves to a type.
+            testCase.verifyEmpty( ...
+                library.InstanceTable(library.InstanceTable.Type == "", :), ...
+                'Every instance of the selected version must resolve to a type.')
         end
 
         function testModelVersionWithoutInstancesIsReported(testCase)

tools/tests/unitTests/SelectModelVersionTest.m

@@ -0,0 +1,49 @@
+classdef SelectModelVersionTest < matlab.unittest.TestCase
+% SelectModelVersionTest - Tests for selecting a model version within a session
+%
+%   A model version is selected by putting its generated classes on the
+%   search path. MATLAB reads a class definition from the path again only
+%   once nothing holds an instance of it, so anything the toolbox itself
+%   keeps across a switch pins the classes of the previous version.
+
+    methods (Test)
+        function testTheTypeRegistryDoesNotPinThePreviousVersion(testCase)
+        % The type registry holds enumeration values of the version it was
+        % built for. Left in place across a switch, it kept the previous
+        % version's Types enumeration in memory, and the instance library
+        % then resolved the selected version's instances against it: every
+        % type the two versions do not share came out untyped.
+        %
+        % The two versions are numbered ones, which are pinned to a schema
+        % commit and do not change, unlike latest. They are chosen for
+        % what tells them apart: v5.0 declares AnatomicalAtlas, which v3.0
+        % calls BrainAtlas. The first is selected here rather than assumed,
+        % so that the test does not pass for nothing in a session that is
+        % on v3.0 or v4.0 already.
+
+            import ommtest.helper.ModelVersionFixture
+
+            testCase.applyFixture(ModelVersionFixture("v5.0"))
+            testCase.assertTrue(ismember("AnatomicalAtlas", typesInMemory()), ...
+                'v5.0 is pinned and declares AnatomicalAtlas; something changed it.')
+
+            % Held, as a session that has looked any type up holds it.
+            openminds.introspection.internal.MetaTypeRegistry.getSingleton();
+
+            testCase.applyFixture(ModelVersionFixture("v3.0"))
+
+            membersInMemory = typesInMemory();
+
+            testCase.verifyTrue(ismember("BrainAtlas", membersInMemory), ...
+                'The Types enumeration in memory must be the selected version''s.')
+            testCase.verifyFalse(ismember("AnatomicalAtlas", membersInMemory), ...
+                'The previous version''s Types enumeration must not stay in memory.')
+        end
+    end
+end
+
+function names = typesInMemory()
+% typesInMemory - The Types enumeration as loaded, not as on the path
+    names = string({ ...
+        meta.class.fromName("openminds.enum.Types").EnumerationMemberList.Name});
+end