From f4f11f60b58dcb0bb7341da339243aa9a7fc8037 Mon Sep 17 00:00:00 2001
From: astaev <astaev@infragistics.com>
Date: Thu, 3 Jan 2019 14:28:13 +0200
Subject: [PATCH] fix(Exporter): #3332 Improve the fix and test

---
 .../excel/excel-exporter-grid.spec.ts         | 26 +++++++++++++++++++
 .../exporter-common/base-export-service.ts    |  3 +--
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/projects/igniteui-angular/src/lib/services/excel/excel-exporter-grid.spec.ts b/projects/igniteui-angular/src/lib/services/excel/excel-exporter-grid.spec.ts
index ff6e7a45a74..f645446d478 100644
--- a/projects/igniteui-angular/src/lib/services/excel/excel-exporter-grid.spec.ts
+++ b/projects/igniteui-angular/src/lib/services/excel/excel-exporter-grid.spec.ts
@@ -470,6 +470,32 @@ describe('Excel Exporter', () => {
                 error = ex.message;
             }
             expect(error).toMatch('Can create an outline of up to eight levels!');
+
+            treeGrid.deleteRowById(9);
+            fix.detectChanges();
+            await wait(16);
+
+            error = '';
+            try {
+                exporter.export(treeGrid, options);
+                await wait();
+            } catch (ex) {
+                error = ex.message;
+            }
+            expect(error).toEqual('');
+
+            treeGrid.addRow({ ID: 9, ParentID: 8, Name: 'Test', JobTitle: '', Age: 49 });
+            fix.detectChanges();
+            await wait(16);
+
+            error = '';
+            try {
+                exporter.export(treeGrid, options);
+                await wait();
+            } catch (ex) {
+                error = ex.message;
+            }
+            expect(error).toMatch('Can create an outline of up to eight levels!');
         });
     });
 
diff --git a/projects/igniteui-angular/src/lib/services/exporter-common/base-export-service.ts b/projects/igniteui-angular/src/lib/services/exporter-common/base-export-service.ts
index 42b22eb17f9..07b18db4f34 100644
--- a/projects/igniteui-angular/src/lib/services/exporter-common/base-export-service.ts
+++ b/projects/igniteui-angular/src/lib/services/exporter-common/base-export-service.ts
@@ -192,6 +192,7 @@ export abstract class IgxBaseExporter {
     }
 
     private prepareData(grid: any, options: IgxExporterOptionsBase): any[] {
+        this.flatRecords = [];
         let rootRecords = grid.rootRecords;
         this._isTreeGrid = rootRecords !== undefined;
 
@@ -210,7 +211,6 @@ export abstract class IgxBaseExporter {
             };
 
             if (this._isTreeGrid) {
-                this.flatRecords = [];
                 rootRecords = DataUtil.treeGridFilter(rootRecords, filteringState);
                 this.prepareHierarchicalData(rootRecords);
                 data = this.flatRecords;
@@ -225,7 +225,6 @@ export abstract class IgxBaseExporter {
             this._sort = cloneValue(grid.sortingExpressions[0]);
 
             if (this._isTreeGrid) {
-                this.flatRecords = [];
                 rootRecords = DataUtil.treeGridSort(rootRecords, grid.sortingExpressions);
                 this.prepareHierarchicalData(rootRecords);
                 data = this.flatRecords;