diff --git a/client/src/store/reducer.test.ts b/client/src/store/reducer.test.ts
index 6f35c0f4..1ac5057b 100644
--- a/client/src/store/reducer.test.ts
+++ b/client/src/store/reducer.test.ts
@@ -6,9 +6,11 @@ import {validFeatureModel} from '../fixtures';
 import FeatureModel from '../modeling/FeatureModel';
 import {initialState, FeatureDiagramCollaborativeSession, State} from './types';
 import logger from '../helpers/logger';
+import {getCurrentArtifactPath} from '../router';
 
 jest.mock('../helpers/logger');
 jest.mock('../modeling/Kernel');
+jest.mock('../router');
 
 describe('reducer', () => {
     const artifactPath = {project: 'project', artifact: 'artifact'},
@@ -23,10 +25,11 @@ describe('reducer', () => {
                     selectedFeatureIDs: [],
                     kernelFeatureModel: kernelFeatureModel,
                     kernelContext: {} // assume no kernel in the unit tests
-                }],
-                currentArtifactPath: artifactPath
+                }]
             });
 
+    beforeEach(() => (getCurrentArtifactPath as jest.Mock).mockReturnValue(artifactPath));
+
     it('returns the initial state', () => {
         expect(reducer()).toBe(initialState);
     });
@@ -145,9 +148,8 @@ describe('reducer', () => {
                     expect((<FeatureDiagramCollaborativeSession>state.collaborativeSessions[0]).isSelectMultipleFeatures).toBe(true);
                 });
 
-                it('does nothing if no feature model is available', () => {
-                    const state = reducer(undefined, actions.ui.featureDiagram.feature.selectAll());
-                    expect(state).toEqual(initialState);
+                it('throws if no feature model is available', () => {
+                    expect(() => reducer(undefined, actions.ui.featureDiagram.feature.selectAll())).toThrow();
                 });
             });
 
@@ -166,9 +168,8 @@ describe('reducer', () => {
                     expect((<FeatureDiagramCollaborativeSession>state.collaborativeSessions[0]).isSelectMultipleFeatures).toBe(false);
                 });
 
-                it('does nothing if no feature model is available', () => {
-                    const state = reducer(undefined, actions.ui.featureDiagram.feature.deselectAll());
-                    expect(state).toEqual(initialState);
+                it('throws if no feature model is available', () => {
+                    expect(() => reducer(undefined, actions.ui.featureDiagram.feature.deselectAll())).toThrow();
                 });
             });
 
@@ -184,9 +185,8 @@ describe('reducer', () => {
                     expect((<FeatureDiagramCollaborativeSession>state.collaborativeSessions[0]).selectedFeatureIDs).not.toContain('FeatureHouse');
                 });
 
-                it('does nothing if no feature model is available', () => {
-                    const state = reducer(undefined, actions.ui.featureDiagram.feature.collapseAll());
-                    expect(state).toEqual(initialState);
+                it('throws if no feature model is available', () => {
+                    expect(() => reducer(undefined, actions.ui.featureDiagram.feature.collapseAll())).toThrow();
                 });
             });
 
@@ -198,9 +198,8 @@ describe('reducer', () => {
                     expect((<FeatureDiagramCollaborativeSession>state.collaborativeSessions[0]).collapsedFeatureIDs).toHaveLength(0);
                 });
 
-                it('does nothing if no feature model is available', () => {
-                    const state = reducer(undefined, actions.ui.featureDiagram.feature.expandAll());
-                    expect(state).toEqual(initialState);
+                it('throws if no feature model is available', () => {
+                    expect(() => reducer(undefined, actions.ui.featureDiagram.feature.expandAll())).toThrow();
                 });
             });
         });
@@ -208,12 +207,14 @@ describe('reducer', () => {
         describe('overlay', () => {
             describe('show overlay', () => {
                 it('shows the about panel', () => {
+                    (getCurrentArtifactPath as jest.Mock).mockReturnValue(undefined);
                     const state = reducer(undefined, actions.ui.overlay.show({overlay: OverlayType.aboutPanel, overlayProps: {}}));
                     expect(state.overlay).toBe(OverlayType.aboutPanel);
                     expect(state.overlayProps).toEqual({});
                 });
     
                 it('shows a feature callout', () => {
+                    (getCurrentArtifactPath as jest.Mock).mockReturnValue(undefined);
                     let state = reducer(undefined, actions.ui.overlay.show({overlay: OverlayType.featureCallout, overlayProps: {featureID: 'FeatureIDE'}}));
                     expect(state.overlay).toBe(OverlayType.featureCallout);
                     expect(state.overlayProps).toEqual({featureID: 'FeatureIDE'});
@@ -231,6 +232,7 @@ describe('reducer', () => {
 
             describe('hide overlay', () => {
                 it('hides an overlay after showing it', () => {
+                    (getCurrentArtifactPath as jest.Mock).mockReturnValue(undefined);
                     let state = reducer(undefined, actions.ui.overlay.show({overlay: OverlayType.aboutPanel, overlayProps: {}}));
                     expect(state.overlay).toBe(OverlayType.aboutPanel);
                     expect(state.overlayProps).toEqual({});
@@ -240,6 +242,7 @@ describe('reducer', () => {
                 });
 
                 it('does nothing if the currently shown overlay is of another type', () => {
+                    (getCurrentArtifactPath as jest.Mock).mockReturnValue(undefined);
                     let state = reducer(undefined, actions.ui.overlay.show({overlay: OverlayType.aboutPanel, overlayProps: {}}));
                     expect(state.overlay).toBe(OverlayType.aboutPanel);
                     expect(state.overlayProps).toEqual({});
diff --git a/client/src/store/selectors.test.ts b/client/src/store/selectors.test.ts
deleted file mode 100644
index 3b02f280..00000000
--- a/client/src/store/selectors.test.ts
+++ /dev/null
@@ -1,80 +0,0 @@
-/*import {getCurrentFeatureModel} from './selectors';
-import {validFeatureModel, invalidFeatureModel} from '../fixtures';
-import FeatureModel from '../modeling/FeatureModel';
-import {initialState} from './types';*/
-
-describe('selectors', () => {
-    /*describe('getCurrentFeatureModel', () => {
-        it('gets no feature model from the initial store state', () => {
-            expect(getCurrentFeatureModel(initialState)).toBeUndefined();
-        });
-
-        it('gets a feature model from a loaded store state', () => {
-            const state = <any>{
-                collaborativeSessions: [{
-                    artifactPath: {project: 'project', artifact: 'artifact'},
-                    kernelContext: {},
-                    kernelFeatureModel: validFeatureModel,
-                    collapsedFeatureIDs: []
-                }],
-                currentArtifactPath: {project: 'project', artifact: 'artifact'}
-            };
-            expect(getCurrentFeatureModel(state)!.kernelFeatureModel)
-                .toEqual(FeatureModel.fromKernel(validFeatureModel).toKernel());
-        });
-
-        it('recomputes when the store state changes', () => {
-            const collaborativeSessions = [{
-                    artifactPath: {project: 'project', artifact: 'artifact'},
-                    kernelContext: {},
-                    kernelFeatureModel: invalidFeatureModel,
-                    collapsedFeatureIDs: ['test1']
-                }],
-                currentArtifactPath = {project: 'project', artifact: 'artifact'};
-                getCurrentFeatureModel.resetRecomputations();
-
-            let state: any = {collaborativeSessions, currentArtifactPath};
-            getCurrentFeatureModel(state);
-            expect(getCurrentFeatureModel.recomputations()).toBe(1);
-
-            state = {collaborativeSessions, currentArtifactPath};
-            getCurrentFeatureModel(state);
-            expect(getCurrentFeatureModel.recomputations()).toBe(1);
-
-            state = {collaborativeSessions, currentArtifactPath};
-            state.collaborativeSessions = [{
-                artifactPath: {project: 'project', artifact: 'artifact'},
-                kernelContext: {},
-                kernelFeatureModel: validFeatureModel,
-                collapsedFeatureIDs: ['test1']
-            }];
-            getCurrentFeatureModel(state);
-            expect(getCurrentFeatureModel.recomputations()).toBe(2);
-
-            state = {collaborativeSessions: state.collaborativeSessions, currentArtifactPath};
-            state.collaborativeSessions = [state.collaborativeSessions[0]];
-            getCurrentFeatureModel(state);
-            expect(getCurrentFeatureModel.recomputations()).toBe(2);
-
-            state = {collaborativeSessions: state.collaborativeSessions, currentArtifactPath};
-            state.collaborativeSessions = [{
-                artifactPath: {project: 'project', artifact: 'artifact'},
-                kernelContext: {},
-                kernelFeatureModel: validFeatureModel,
-                collapsedFeatureIDs: []
-            }];
-            getCurrentFeatureModel(state);
-            expect(getCurrentFeatureModel.recomputations()).toBe(3);
-
-            state = {collaborativeSessions: state.collaborativeSessions, currentArtifactPath};
-            state.collaborativeSessions = [{
-                artifactPath: {project: 'project', artifact: 'artifact'},
-                kernelContext: {},
-                kernelFeatureModel: validFeatureModel,
-                collapsedFeatureIDs: state.collaborativeSessions[0].collapsedFeatureIDs
-            }];
-            getCurrentFeatureModel(state);
-            expect(getCurrentFeatureModel.recomputations()).toBe(3);
-        });
-    });*/
-});
\ No newline at end of file
diff --git a/client/src/store/selectors.ts b/client/src/store/selectors.ts
index e06bf28a..e79bf87c 100644
--- a/client/src/store/selectors.ts
+++ b/client/src/store/selectors.ts
@@ -8,7 +8,7 @@ import createCachedSelector from 're-reselect';
 import FeatureModel from '../modeling/FeatureModel';
 import {State, CollaborativeSession, FeatureDiagramCollaborativeSession} from './types';
 import logger from '../helpers/logger';
-import {ArtifactPath, isArtifactPathEqual, artifactPathToString} from '../types';
+import {ArtifactPath, isArtifactPathEqual, artifactPathToString, artifactPathCacheKey} from '../types';
 import {KernelFeatureModel} from '../modeling/types';
 import {getCurrentArtifactPath} from '../router';
 
@@ -36,7 +36,7 @@ const lookupCollaborativeSession = (collaborativeSessions: CollaborativeSession[
 export const getCollaborativeSession = createCachedSelector(
     (state: State, artifactPath: ArtifactPath) => lookupCollaborativeSession(state.collaborativeSessions, artifactPath),
     collaborativeSession => collaborativeSession)(
-        (_state: State, artifactPath: ArtifactPath) => artifactPathToString(artifactPath));
+        (_state: State, artifactPath: ArtifactPath) => artifactPathCacheKey(artifactPath));
 
 export function getCurrentCollaborativeSession(state: State): CollaborativeSession | undefined {
     const currentArtifactPath = getCurrentArtifactPath(state.collaborativeSessions);
@@ -59,7 +59,7 @@ export const getFeatureModel = createCachedSelector(
             return undefined;
         return FeatureModel.fromKernel(kernelFeatureModel).collapse(collapsedFeatureIDs);
     }
-)((_state: State, artifactPath: ArtifactPath) => artifactPathToString(artifactPath));
+)((_state: State, artifactPath: ArtifactPath) => artifactPathCacheKey(artifactPath));
 
 export function getCurrentFeatureModel(state: State): FeatureModel | undefined {
     const currentArtifactPath = getCurrentArtifactPath(state.collaborativeSessions);
diff --git a/client/src/types.ts b/client/src/types.ts
index 6bb93d22..59dae032 100644
--- a/client/src/types.ts
+++ b/client/src/types.ts
@@ -65,6 +65,10 @@ export function artifactPathToString(artifactPath: ArtifactPath): string {
     return artifactPath ? `${artifactPath.project}/${artifactPath.artifact}` : `(unknown artifact)`;
 }
 
+export function artifactPathCacheKey(artifactPath: ArtifactPath): string {
+    return artifactPath ? `${artifactPath.project.toLowerCase()}/${artifactPath.artifact.toLowerCase()}` : '';
+}
+
 export function isArtifactPathEqual(a?: ArtifactPath, b?: ArtifactPath): boolean {
     return typeof a !== 'undefined' && typeof b !== 'undefined' &&
         a.project.toLowerCase() === b.project.toLowerCase() && a.artifact.toLowerCase() === b.artifact.toLowerCase();