chore(*): using column sortStrategy for sorting

Author: igdmdimitrov

projects/igniteui-angular/src/lib/grids/filtering/excel-style/grid.excel-style-filtering.component.ts

@@ -29,7 +29,6 @@ import { DisplayDensity } from '../../../core/density';
 import { GridSelectionMode } from '../../common/enums';
 import { GridBaseAPIService } from '../../api.service';
 import { SortingDirection } from '../../../data-operations/sorting-expression.interface';
-import { IgxSorting } from '../../../data-operations/sorting-strategy';
 
 /**
  * @hidden
@@ -559,14 +558,8 @@ export class IgxGridExcelStyleFilteringComponent implements OnDestroy {
             this.addItems(shouldUpdateSelection);
         }
 
-        const sorting = new IgxSorting();
-        const expressions = [{
-            dir: SortingDirection.Asc,
-            fieldName: 'value',
-            ignoreCase: this.column.filteringIgnoreCase,
-            strategy: this.column.sortStrategy
-        }];
-        this.listData = sorting.sort(this.listData, expressions);
+        this.listData = this.column.sortStrategy.sort(this.listData, 'value', SortingDirection.Asc, this.column.sortingIgnoreCase,
+            (obj, key) => obj[key]);
 
         if (this.containsNullOrEmpty) {
             this.addBlanksItem(shouldUpdateSelection);
@@ -709,7 +702,7 @@ export class IgxGridExcelStyleFilteringComponent implements OnDestroy {
         this.listData.unshift(blanks);
     }
 
-    private getFilterItemLabel(element: any, applyFormatter: boolean = true) {
+    private getFilterItemLabel(element: any) {
         if (this.column.dataType === DataType.Date) {
             return element && element.label ? element.label : this.column.formatter ?
                 this.column.formatter(element) :

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

@@ -4822,7 +4822,7 @@ describe('IgxGrid - Filtering actions - Excel style filtering #grid', () => {
             fix.detectChanges();
 
             verifyExcelStyleFilterAvailableOptions(fix,
-                ['Select All', 'Custom', 'a', 'custoM', 'custom'],
+                ['Select All', 'a', 'Custom', 'custoM', 'custom'],
                 [true, true, true, true, true]);
         }));
 
@@ -5153,7 +5153,7 @@ describe('IgxGrid - Filtering actions - Excel style filtering #grid', () => {
             expect(listItems[3].innerText).toBe('Yes', 'incorrect list item label');
         }));
 
-        it('Should sort items in excel style search case INsensitive', fakeAsync(() => {
+        it('Should sort items in excel style search correctly', fakeAsync(() => {
             const data = [
                 {
                     Downloads: 254,
@@ -5183,12 +5183,12 @@ describe('IgxGrid - Filtering actions - Excel style filtering #grid', () => {
             fix.componentInstance.data = data;
             fix.detectChanges();
 
-            // Open excel style custom filtering dialog.
+            // Open excel style custom filtering dialog for string column
             GridFunctions.clickExcelFilterIcon(fix, 'AnotherField');
             tick(100);
             fix.detectChanges();
 
-            // Verify items order
+            // Verify items order is case INsensitive
             verifyExcelStyleFilterAvailableOptions(fix,
                 ['Select All', 'aWord', 'BWord'],
                 [true, true, true]);