From 1fd45cf1498687e4814bbfe60c7a1478a6077b87 Mon Sep 17 00:00:00 2001
From: Hristo Anastasov <HAnastasov@infragistics.com>
Date: Tue, 30 Oct 2018 11:32:10 +0200
Subject: [PATCH] fix(grid): use the correct column strategy if sorting via the
 api #2734

---
 projects/igniteui-angular/src/lib/grids/api.service.ts        | 4 ++--
 .../igniteui-angular/src/lib/grids/grid/grid-api.service.ts   | 3 ++-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/projects/igniteui-angular/src/lib/grids/api.service.ts b/projects/igniteui-angular/src/lib/grids/api.service.ts
index 2b82fc97bf6..f8caf822045 100644
--- a/projects/igniteui-angular/src/lib/grids/api.service.ts
+++ b/projects/igniteui-angular/src/lib/grids/api.service.ts
@@ -336,7 +336,7 @@ export class GridBaseAPIService <T extends IgxGridBaseComponent> {
             this.remove_grouping_expression(id, fieldName);
         }
         const sortingState = cloneArray(this.get(id).sortingExpressions);
-
+        strategy = strategy ? strategy : this.get_column_by_name(this.get(id).id, fieldName).sortStrategy;
         this.prepare_sorting_expression([sortingState], { fieldName, dir, ignoreCase, strategy });
         this.get(id).sortingExpressions = sortingState;
     }
@@ -348,6 +348,7 @@ export class GridBaseAPIService <T extends IgxGridBaseComponent> {
             if (each.dir === SortingDirection.None) {
                 this.remove_grouping_expression(id, each.fieldName);
             }
+            each.strategy = each.strategy ? each.strategy : this.get_column_by_name(this.get(id).id, each.fieldName).sortStrategy;
             this.prepare_sorting_expression([sortingState], each);
         }
 
@@ -458,7 +459,6 @@ export class GridBaseAPIService <T extends IgxGridBaseComponent> {
     }
 
     protected prepare_sorting_expression(stateCollections: Array<Array<any>>, expression: ISortingExpression) {
-        DataUtil.mergeDefaultProperties(expression, SortingStateDefaults);
         if (expression.dir === SortingDirection.None) {
             stateCollections.forEach(state => {
                 state.splice(state.findIndex((expr) => expr.fieldName === expression.fieldName), 1);
diff --git a/projects/igniteui-angular/src/lib/grids/grid/grid-api.service.ts b/projects/igniteui-angular/src/lib/grids/grid/grid-api.service.ts
index c15bf491756..d2e4f97f41f 100644
--- a/projects/igniteui-angular/src/lib/grids/grid/grid-api.service.ts
+++ b/projects/igniteui-angular/src/lib/grids/grid/grid-api.service.ts
@@ -12,7 +12,7 @@ export class IgxGridAPIService extends GridBaseAPIService<IgxGridComponent> {
     public groupBy(id: string, fieldName: string, dir: SortingDirection, ignoreCase: boolean, strategy: ISortingStrategy): void {
         const groupingState = cloneArray(this.get(id).groupingExpressions);
         const sortingState = cloneArray(this.get(id).sortingExpressions);
-
+        strategy = strategy ? strategy : this.get_column_by_name(this.get(id).id, fieldName).sortStrategy;
         this.prepare_sorting_expression([sortingState, groupingState], { fieldName, dir, ignoreCase, strategy });
         this.get(id).groupingExpressions = groupingState;
         this.arrange_sorting_expressions(id);
@@ -23,6 +23,7 @@ export class IgxGridAPIService extends GridBaseAPIService<IgxGridComponent> {
         const sortingState = cloneArray(this.get(id).sortingExpressions);
 
         for (const each of expressions) {
+            each.strategy = each.strategy ? each.strategy : this.get_column_by_name(this.get(id).id, each.fieldName).sortStrategy;
             this.prepare_sorting_expression([sortingState, groupingState], each);
         }