Fixes exception when hitting the return key on editable collection vi…

…ew with no selection. Refactored the method to prevent attempting to edit invalid item views. Includes unit test.

frameworks/desktop/tests/views/collection/keyboard.js

@@ -63,4 +63,23 @@ test("deselectAll", function() {
 	equals(view.getPath('selection.length'), 10, "deselectAll has no effect when allowsEmptySelection is NO")
 });
 
+// There was a specific bug in which insertNewLine when no selection was set, but
+// isEditable & canEditContent were true, that it would throw an exception.
+test("insertNewline doesn't throw exception when no selection", function() {
+	var collection = pane.view('default');
+
+	// Prep.
+	collection.set('isEditable', true);
+	collection.set('canEditContent', true);
+
+	SC.run(function() {
+		try {
+			collection.insertNewline();
+			ok(true, "Calling insertNewline without a selection should not throw an exception.");
+		} catch (ex) {
+			ok(false, "Calling insertNewline without a selection should not throw an exception. %@".fmt(ex));
+		}
+	});
+});
+
 // TODO: yeah all the other keyboard stuff.

frameworks/desktop/views/collection.js

@@ -2024,30 +2024,28 @@ SC.CollectionView = SC.View.extend(SC.CollectionViewDelegate, SC.CollectionConte
     otherwise, invoke action.
   */
   insertNewline: function (sender, evt) {
-    var canEdit = this.get('isEditable') && this.get('canEditContent'),
-        sel, content, set, idx, itemView;
+    var wantsEdit = this.get('isEditable') && this.get('canEditContent'),
+      canEdit = true, //false,
+      sel, content, set, idx, itemView;
 
-    // first make sure we have a single item selected; get idx
-    if (canEdit) {
+    // Make sure we have a single item selected and the item view supports beginEditing
+    if (wantsEdit) {
       sel     = this.get('selection');
       content = this.get('content');
+
       if (sel && sel.get('length') === 1) {
         set = sel.indexSetForSource(content);
         idx = set ? set.get('min') : -1;
-        canEdit = idx >= 0;
-      }
-    }
 
-    // next find itemView and ensure it supports editing
-    if (canEdit) {
-      itemView = this.itemViewForContentIndex(idx);
-      canEdit = itemView && SC.typeOf(itemView.beginEditing) === SC.T_FUNCTION;
+        // next find itemView and ensure it supports editing
+        itemView = this.itemViewForContentIndex(idx);
+        canEdit = itemView && SC.typeOf(itemView.beginEditing) === SC.T_FUNCTION;
+      }
     }
 
     // ok, we can edit..
     if (canEdit) {
       this.scrollToContentIndex(idx);
-      itemView = this.itemViewForContentIndex(idx); // just in case
       itemView.beginEditing();
 
     // invoke action