Merge pull request #3241 from ProjectMirador/3240-merge-nonrecursive

Avoid lodash-merge, which is recursive and can lead to surprises

src/state/reducers/companionWindows.js

 import omit from 'lodash/omit';
 import set from 'lodash/fp/set';
 import update from 'lodash/fp/update';
-import merge from 'lodash/fp/merge';
 import ActionTypes from '../actions/action-types';
 
 /** */
@@ -31,14 +30,14 @@ export function companionWindowsReducer(state = {}, action) {
         return object;
       }, {});
     case ActionTypes.UPDATE_COMPANION_WINDOW:
-      return update([action.id], orig => merge(orig, action.payload), state);
+      return update([action.id], orig => ({ ...(orig || {}), ...action.payload }), state);
 
     case ActionTypes.REMOVE_COMPANION_WINDOW:
       return omit(state, action.id);
     case ActionTypes.IMPORT_MIRADOR_STATE:
       return action.state.companionWindows || [];
     case ActionTypes.TOGGLE_TOC_NODE:
-      return update([action.id, 'tocNodes'], orig => merge(orig || {}, action.payload), state);
+      return update([action.id, 'tocNodes'], orig => ({ ...(orig || {}), ...action.payload }), state);
     default:
       return state;
   }

src/state/reducers/elasticLayout.js

 import update from 'lodash/fp/update';
 import omit from 'lodash/omit';
-import merge from 'lodash/fp/merge';
 import ActionTypes from '../actions/action-types';
 
 /**
@@ -17,7 +16,7 @@ export const elasticLayoutReducer = (state = {}, action) => {
       };
 
     case ActionTypes.UPDATE_ELASTIC_WINDOW_LAYOUT:
-      return update([action.windowId], orig => merge(orig, action.payload), state);
+      return update([action.windowId], orig => ({ ...(orig || {}), ...action.payload }), state);
 
     case ActionTypes.REMOVE_WINDOW:
       return omit(state, action.windowId);

src/state/reducers/windows.js

 import update from 'lodash/fp/update';
 import omit from 'lodash/omit';
-import merge from 'lodash/fp/merge';
 import ActionTypes from '../actions/action-types';
 
 /**
@@ -29,7 +28,7 @@ export const windowsReducer = (state = {}, action) => {
       };
 
     case ActionTypes.UPDATE_WINDOW:
-      return update([action.id], orig => merge(orig, action.payload), state);
+      return update([action.id], orig => ({ ...(orig || {}), ...action.payload }), state);
 
     case ActionTypes.REMOVE_WINDOW:
       return omit(state, [action.windowId]);
@@ -72,7 +71,9 @@ export const windowsReducer = (state = {}, action) => {
     case ActionTypes.SET_CANVAS:
       if (!state[action.windowId]) return state;
 
-      return update([action.windowId], orig => merge(orig, {
+      return update([action.windowId], orig => (
+        {
+          ...(orig || {}),
           canvasId: action.canvasId,
           visibleCanvases: action.visibleCanvases || [],
         }), state);