fix(esf): prevent error for untyped non-string columns when filtering grid (#15453)

* fix(esf): check for untyped non-string columns when filtering grid through esf
---------

Co-authored-by: Galina Edinakova <[email protected]>

Author: teodosiah

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

@@ -549,7 +549,7 @@ export class IgxGridExcelStyleFilteringComponent extends BaseFilteringComponent
         const lowerCaseFilterValues = new Set(Array.from(expr.expression.searchVal).map((value: string) => value.toLowerCase()));
 
         this.grid.data.forEach(item => {
-            if (lowerCaseFilterValues.has(item[this.column.field]?.toLowerCase())) {
+            if (typeof item[this.column.field] === "string" && lowerCaseFilterValues.has(item[this.column.field]?.toLowerCase())) {
                 expr.expression.searchVal.add(item[this.column.field]);
             }
         });

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

@@ -13,6 +13,7 @@ import { GridFunctions } from '../../test-utils/grid-functions.spec';
 import { UIInteractions } from '../../test-utils/ui-interactions.spec';
 import { SampleTestData } from '../../test-utils/sample-test-data.spec';
 import { By } from '@angular/platform-browser';
+import { GridColumnDataType } from '../../data-operations/data-util';
 
 const IGX_CHECKBOX_LABEL = '.igx-checkbox__label';
 
@@ -751,6 +752,29 @@ describe('IgxTreeGrid - Filtering actions #tGrid', () => {
             emptyTextEl = searchComponent.querySelector('.igx-excel-filter__empty');
             expect(emptyTextEl.innerText).toEqual('No matches');
         }));
+
+        it('Should not throw console error when number column with dataType string is filtered.', fakeAsync(() => {
+            tGrid.columns[0].dataType = GridColumnDataType.String;
+            fix.detectChanges();
+            spyOn(console, 'error');
+            
+            GridFunctions.clickExcelFilterIcon(fix, 'ID');
+            fix.detectChanges();
+            tick();
+
+            const excelMenu = GridFunctions.getExcelStyleFilteringComponent(fix, 'igx-tree-grid');
+            const checkboxes: any[] = Array.from(GridFunctions.getExcelStyleFilteringCheckboxes(fix, excelMenu, 'igx-tree-grid'));
+
+            checkboxes[2].click();
+            tick();
+            fix.detectChanges();
+
+            GridFunctions.clickApplyExcelStyleFiltering(fix, null, 'igx-tree-grid');
+            fix.detectChanges();
+            tick();
+            
+            expect(console.error).not.toHaveBeenCalled();
+        }));
     });
 
     describe('Tree grid ESF templates', () => {