Merge branch '8.1.x' into mkirova/fix-4416-master

Author: mpavlinov

projects/igniteui-angular/src/lib/grids/filtering/excel-style/excel-style-search.pipe.ts

@@ -19,7 +19,7 @@ export class IgxExcelStyleSearchFilterPipe implements PipeTransform {
 
         searchText = searchText.toLowerCase();
         const result = items.filter((it, i) => (i === 0 && it.isSpecial) ||
-            (it.value || it.value === 0) &&
+            (it.value !== null && it.value !== undefined) &&
             it.value.toString().toLowerCase().indexOf(searchText) > -1);
 
         return result.length > 1 ? result : [];

projects/igniteui-angular/src/lib/grids/grid/grid-filtering-ui.spec.ts

@@ -4420,6 +4420,26 @@ describe('IgxGrid - Filtering actions - Excel style filtering', () => {
             fix.detectChanges();
         }));
 
+        it('Should include \'false\' value in results when searching.', fakeAsync(() => {
+            // Open excel style custom filtering dialog.
+            GridFunctions.clickExcelFilterIcon(fix, 'Released');
+            fix.detectChanges();
+
+            // Type string in search box.
+            const searchComponent = GridFunctions.getExcelStyleSearchComponent(fix);
+            const inputNativeElement = searchComponent.querySelector('.igx-input-group__input');
+            sendInputNativeElement(inputNativeElement, 'false', fix);
+            tick(100);
+            fix.detectChanges();
+
+            // Verify that the first item is 'Select All' and the second item is 'false'.
+            const listItems = GridFunctions.sortNativeElementsVertically(
+                Array.from(searchComponent.querySelectorAll('igx-list-item')));
+            expect(listItems.length).toBe(2, 'incorrect rendered list items count');
+            expect(listItems[0].innerText).toBe('Select All');
+            expect(listItems[1].innerText).toBe('false');
+        }));
+
         it('should scroll items in search list correctly', (async () => {
             // Add additional rows as prerequisite for the test
             for (let index = 0; index < 30; index++) {