chore(combo): move diffInSets definition to combo, update README.md

Author: ViktorSlavov

CHANGELOG.md

@@ -2,7 +2,7 @@
 
 All notable changes for each version of this project will be documented in this file.
 
-## 8.2.0
+## 8.1.3
 - `IgxCombo`
     - Combo `onSelectionChange` events now emits the item(s) that were added to or removed from the collection:
     ```html
@@ -11,44 +11,18 @@ All notable changes for each version of this project will be documented in this
     ```typescript
         export class Example {
             ...
-            handleChange(event: {
-                newSelection: any[],
-                oldSelection: any[],
-                added: any[], // the items added to the selection in this change
-                removed: any[], // the items removed for the selection in this change
-                ... 
-            }) {
-            console.log("Items added: ", [...event.added]);
-            console.log("Items removed: ", [...event.removed]);
+            handleChange(event: IComboSelectionChangeEventArgs) {
+            console.log("Items added: ", [...event.added]); // the items added to the selection in this change
+            console.log("Items removed: ", [...event.removed]); // the items removed from the selection in this change
             }
         }
     ```
-    
+
 ## 8.1.2
 
 ### New Features
 - `IgxDatePicker`
     - `valueChange` event is added.
-- `IgxCombo`
-    - Combo `onSelectionChange` events now emits the item(s) that were added to or removed from the collection:
-    ```html
-    <igx-combo (onSelectionChange)="handleChange($event)">
-    ```
-    ```typescript
-        export class Example {
-            ...
-            handleChange(event: {
-                newSelection: any[],
-                oldSelection: any[],
-                added: any[], // the items added to the selection in this change
-                removed: any[], // the items removed for the selection in this change
-                ... 
-            }) {
-            console.log("Items added: ", [...event.added]);
-            console.log("Items removed: ", [...event.removed]);
-            }
-        }
-    ```
 
 ## 8.1.0
 

projects/igniteui-angular/src/lib/combo/README.md

@@ -276,7 +276,7 @@ Setting `[displayDensity]` affects the control's items' and inputs' css properti
 
 | Name                | Description                                                             | Cancelable   | Parameters                              |
 |------------------   |-------------------------------------------------------------------------|------------- |-----------------------------------------|
-| `onSelectionChange` | Emitted when item selection is changing, before the selection completes | true         | { oldSelection: `any[]`, newSelection: `any[]`, event?: `Event`, added: `any[]`, removed: `any[]`, cancel: `boolean` } |
+| `onSelectionChange` | Emitted when item selection is changing, before the selection completes | true         | [`IComboSelectionChangeEventArgs`](https://www.infragistics.com/products/ignite-ui-angular/docs/typescript/latest/interfaces/icomboselectionchangeeventargs.html) |
 | `onSearchInput`     | Emitted when an the search input's input event is triggered             | false        | { searchValue: `string` }               |
 | `onAddition`        | Emitted when an item is being added to the data collection              | false        | { oldCollection: `any[]`, addedItem: `<any>`, newCollection: `any[]` }|
 | `onDataPreLoad`     | Emitted when new chunk of data is loaded from the virtualization        | false        | { event: `Event` }                        |

projects/igniteui-angular/src/lib/combo/combo.component.ts

@@ -17,7 +17,7 @@ import {
 import { FormsModule, ReactiveFormsModule, ControlValueAccessor, NG_VALUE_ACCESSOR, NgControl } from '@angular/forms';
 import { IgxCheckboxModule } from '../checkbox/checkbox.component';
 import { IgxSelectionAPIService } from '../core/selection';
-import { cloneArray, CancelableEventArgs, CancelableBrowserEventArgs, diffInSets } from '../core/utils';
+import { cloneArray, CancelableEventArgs, CancelableBrowserEventArgs } from '../core/utils';
 import { IgxStringFilteringOperand, IgxBooleanFilteringOperand } from '../data-operations/filtering-condition';
 import { FilteringLogic, IFilteringExpression } from '../data-operations/filtering-expression.interface';
 import { SortingDirection, ISortingExpression } from '../data-operations/sorting-expression.interface';
@@ -83,11 +83,17 @@ export enum IgxComboState {
     INVALID
 }
 
+/** Event emitted when an igx-combo's selection is changing */
 export interface IComboSelectionChangeEventArgs extends CancelableEventArgs {
+    /** An array containing the values that are currently selected */
     oldSelection: any[];
+    /** An array containing the values that will be selected after this event */
     newSelection: any[];
+    /** An array containing the values that will be added to the selection (if any) */
     added: any[];
+    /** An array containing the values that will be removed from the selection (if any) */
     removed: any[];
+    /** The user interaction that triggered the selection change */
     event?: Event;
 }
 
@@ -97,6 +103,20 @@ export interface IComboItemAdditionEvent {
     newCollection: any[];
 }
 
+/**
+ * When called with sets A & B, returns A - B (as array);
+ * @hidden
+ */
+function diffInSets(set1: Set<any>, set2: Set<any>): any[] {
+    const results = [];
+    set1.forEach(entry => {
+        if (!set2.has(entry)) {
+            results.push(entry);
+        }
+    });
+    return results;
+}
+
 let NEXT_ID = 0;
 const noop = () => { };
 
@@ -1498,8 +1518,8 @@ export class IgxComboComponent extends DisplayDensityBase implements IgxComboBas
     }
 
     protected setSelection(newSelection: Set<any>, event?: Event): void {
-        const removed = Array.from(diffInSets(this.selection.get(this.id), newSelection));
-        const added = Array.from(diffInSets(newSelection, this.selection.get(this.id)));
+        const removed = diffInSets(this.selection.get(this.id), newSelection);
+        const added = diffInSets(newSelection, this.selection.get(this.id));
         const oldSelectionEmit = Array.from(this.selection.get(this.id) || []);
         const newSelectionEmit = Array.from(newSelection || []);
         const args: IComboSelectionChangeEventArgs = {

projects/igniteui-angular/src/lib/core/utils.ts

@@ -13,14 +13,6 @@ export function cloneArray(array: any[], deep?: boolean) {
     return arr;
 }
 
-/**
- * When called with sets A & B, returns A - B (as set);
- * @hidden
- */
-export function diffInSets(set1: Set<any>, set2: Set<any>): Set<any> {
-    return new Set(Array.from(set1).filter(entry => !set2.has(entry)));
-}
-
 /**
  * Doesn't clone leaf items
  * @hidden