Fix: Resolve minor JavaScript linting issues and hasOwnProperty warni…

…ng (fixes #571) (#572)

* Fix minor JS linting issues

* Fix hasOwnProperty warning in img.lazyload.js

js/fixes/img.lazyload.js

@@ -34,7 +34,7 @@ function applyImgLoadingFix() {
   Adapt.on('reactElement:preRender', event => {
     if (event.name !== 'img') return;
     const options = event.args[1] = event.args[1] || {};
-    if (options && options.hasOwnProperty('loading')) return;
+    if (options && Object.prototype.hasOwnProperty.call(options, 'loading')) return;
     options.loading = 'eager';
   });
 }

js/models/itemsComponentModel.js

@@ -14,7 +14,7 @@ export default class ItemsComponentModel extends ComponentModel {
     this.setUpItems();
     this.listenTo(this.getChildren(), {
       all: this.onAll,
-      'change': this.storeUserAnswer,
+      change: this.storeUserAnswer,
       'change:_isActive': this.setVisitedStatus,
       'change:_isVisited': this.checkCompletionStatus
     });
@@ -27,7 +27,7 @@ export default class ItemsComponentModel extends ComponentModel {
     this.getChildren().forEach(child => child.set('_isVisited', booleanArray[child.get('_index')]));
   }
 
-  storeUserAnswer() {    
+  storeUserAnswer() {
     const items = this.getChildren().slice(0);
     items.sort((a, b) => a.get('_index') - b.get('_index'));
     const booleanArray = items.map(child => child.get('_isVisited'));

js/router.js

@@ -260,19 +260,19 @@ class Router extends Backbone.Router {
       let _parentId = parentModel.get('_id');
       const built = buildTypes.map((_type, index) => {
         const ModelClass = components.getModelClass({ _type });
-        const _id = `preview-${_type}`
+        const _id = `preview-${_type}`;
         const builtModel = new ModelClass({
           _type,
           _id,
           _parentId,
           _isPreview: true
         });
-        if (index) parentModel.getChildren().add(builtModel)
-        data.add(builtModel)
-        parentModel = builtModel
-        _parentId = _id
-        return builtModel
-      })
+        if (index) parentModel.getChildren().add(builtModel);
+        data.add(builtModel);
+        parentModel = builtModel;
+        _parentId = _id;
+        return builtModel;
+      });
       // Clone the requested content to sanitise
       model.deepClone((clone, orig) => {
         // Make the cloned item available and unlocked
@@ -298,16 +298,16 @@ class Router extends Backbone.Router {
         });
       });
       built.forEach(model => model.setupModel());
-      isContentObject = true
-      model = built[0]
-      model.setOnChildren({ _isPreview : true })
+      isContentObject = true;
+      model = built[0];
+      model.setOnChildren({ _isPreview: true });
     }
 
     const navigateToId = model.get('_id');
 
     // Ensure that the router is rendering a contentobject
     model = isContentObject ? model : model.findAncestor('contentobject');
-    id = model.get('_id');
+    id = navigateToId;
 
     /**
      * TODO:
@@ -351,7 +351,7 @@ class Router extends Backbone.Router {
   }
 
   async removePreviews() {
-    const previews = data.filter(model => model.get('_isPreview'))
+    const previews = data.filter(model => model.get('_isPreview'));
     previews.forEach(model => data.remove(model));
   }
 
@@ -582,7 +582,7 @@ class Router extends Backbone.Router {
   }
 
   onLanguageChange() {
-    this.updateLocation(null, null, null, null)
+    this.updateLocation(null, null, null, null);
   }
 
 }

js/views/buttonsView.js

@@ -191,7 +191,7 @@ export default class ButtonsView extends Backbone.View {
       : isPartlyCorrect
         ? (ariaLabels.answeredPartlyCorrect ?? ariaLabels.answeredIncorrectly)
         : ariaLabels.answeredIncorrectly;
-    
+
     if (!hasSpanAriaLabel) {
       // Backward compability
       $marking.attr('aria-label', correctnessAriaLabel);

js/views/menuItemView.js

@@ -4,7 +4,7 @@ class MenuItemView extends AdaptView {
 
   attributes() {
     return AdaptView.resultExtend('attributes', {
-      'role': 'listitem',
+      role: 'listitem',
       'aria-labelledby': this.model.get('_id') + '-heading'
     }, this);
   }