Object utilities (#729)

* Create utilities

* Rename old isObject

* Use new isObject

* Remove old function

* Add additional function

* Simplify for now

* Rename function for clarity

* Rename function

* Expand type

* Update eslint

1 files changed, 5 insertions, 4 deletions

diff --git a/ext/js/display/display-history.js b/ext/js/display/display-history.js
index bc4f1539..183368d0 100644
--- a/ext/js/display/display-history.js
+++ b/ext/js/display/display-history.js
@@ -17,7 +17,8 @@
  */
 
 import {EventDispatcher} from '../core/event-dispatcher.js';
-import {generateId, isObject} from '../core/utilities.js';
+import {isObjectNotArray} from '../core/object-utilities.js';
+import {generateId} from '../core/utilities.js';
 
 /**
  * @augments EventDispatcher<import('display-history').Events>
@@ -38,12 +39,12 @@ export class DisplayHistory extends EventDispatcher {
 
         const historyState = history.state;
         const {id, state} = (
-            typeof historyState === 'object' && historyState !== null ?
+            isObjectNotArray(historyState) ?
             historyState :
             {id: null, state: null}
         );
         /** @type {?import('display-history').EntryState} */
-        const stateObject = typeof state === 'object' || state === null ? state : null;
+        const stateObject = isObjectNotArray(state) ? state : null;
         /** @type {import('display-history').Entry} */
         this._current = this._createHistoryEntry(id, location.href, stateObject, null, null);
     }
@@ -189,7 +190,7 @@ export class DisplayHistory extends EventDispatcher {
     _updateStateFromHistory() {
         let state = history.state;
         let id = null;
-        if (isObject(state)) {
+        if (isObjectNotArray(state)) {
             id = state.id;
             if (typeof id === 'string') {
                 const entry = this._historyMap.get(id);