fix(esf): don't duplicate records in esf menu when filteringIgnoreCase is true

Author: onlyexeption

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

@@ -599,6 +599,13 @@ export class IgxGridExcelStyleFilteringComponent implements OnDestroy {
 
         this.uniqueValues.forEach(element => {
             if (element !== undefined && element !== null && element !== '') {
+                if (this.column.dataType === DataType.String &&
+                    this.column.filteringIgnoreCase &&
+                    this.listData.length > 0 &&
+                    this.listData.map(el => el.label.toLowerCase()).indexOf(element.toLowerCase()) !== -1) {
+                        return;
+                    }
+
                 const filterListItem = new FilterListItem();
                 if (this.column.filteringExpressionsTree) {
                     if (shouldUpdateSelection) {

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

@@ -4344,6 +4344,33 @@ describe('IgxGrid - Filtering actions - Excel style filtering #grid', () => {
             listItems = GridFunctions.getExcelStyleSearchComponentListItems(fix, searchComponent);
             expect(listItems.length).toBe(0, 'incorrect rendered list items count');
         }));
+
+        it('Should ignore duplicate records when column\'\s filteringIgnoreCase is true', fakeAsync(() => {
+            const column = grid.getColumnByName('AnotherField');
+            expect(column.filteringIgnoreCase).toBeTrue();
+
+            GridFunctions.clickExcelFilterIconFromCode(fix, grid, 'AnotherField');
+            tick(100);
+            fix.detectChanges();
+
+            const searchComponent = GridFunctions.getExcelStyleSearchComponent(fix);
+            const listItems = GridFunctions.getExcelStyleSearchComponentListItems(fix, searchComponent);
+            expect(listItems.length).toBe(3, 'incorrect rendered list items count');
+        }));
+
+        it('Should not ignore duplicate records when column\'\s filteringIgnoreCase is false', fakeAsync(() => {
+            const column = grid.getColumnByName('AnotherField');
+            column.filteringIgnoreCase = false;
+            expect(column.filteringIgnoreCase).toBeFalse();
+
+            GridFunctions.clickExcelFilterIconFromCode(fix, grid, 'AnotherField');
+            tick(100);
+            fix.detectChanges();
+
+            const searchComponent = GridFunctions.getExcelStyleSearchComponent(fix);
+            const listItems = GridFunctions.getExcelStyleSearchComponentListItems(fix, searchComponent);
+            expect(listItems.length).toBe(5, 'incorrect rendered list items count');
+        }));
     });
 
     describe('Templates: ', () => {

projects/igniteui-angular/src/lib/test-utils/grid-samples.spec.ts

@@ -997,7 +997,7 @@ export class CustomFilter extends IgxFilteringOperand {
         <igx-column width="100px" [field]="'ReleaseDate'" [header]="'ReleaseDate'" headerClasses="header-release-date"
             [filterable]="filterable" [resizable]="resizable" dataType="date">
         </igx-column>
-        <igx-column width="100px" [field]="'AnotherField'" [header]="'Anogther Field'" [filterable]="filterable"
+        <igx-column width="100px" [field]="'AnotherField'" [header]="'Another Field'" [filterable]="filterable"
             dataType="string" [filters]="customFilter">
         </igx-column>
     </igx-grid>`

projects/igniteui-angular/src/lib/test-utils/sample-test-data.spec.ts

@@ -1515,15 +1515,15 @@ export class SampleTestData {
             ProductName: 'Some other item with Script',
             ReleaseDate: SampleTestData.timeGenerator.timedelta(SampleTestData.today, 'day', 1),
             Released: null,
-            AnotherField: 'a'
+            AnotherField: 'Custom'
         },
         {
             Downloads: 0,
             ID: 7,
             ProductName: null,
             ReleaseDate: SampleTestData.timeGenerator.timedelta(SampleTestData.today, 'month', 1),
             Released: true,
-            AnotherField: 'a'
+            AnotherField: 'custoM'
         },
         {
             Downloads: 1000,