feat(drp): typing a single value results in calendar range of single date

Author: ddaribo

projects/igniteui-angular/src/lib/date-range-picker/date-range-picker.component.spec.ts

@@ -1129,7 +1129,8 @@ describe('IgxDateRangePicker', () => {
                     expect(endInput.nativeElement.value).toEqual(inputEndDate);
                 });
 
-                it('should select a range from the calendar only when the two inputs are filled in', fakeAsync(() => {
+                it('should select a range from the calendar only when any of the two inputs are filled in', fakeAsync(() => {
+                    // refactored to any of the two inputs, instead of both, to match the behavior in WC - #16131
                     startInput.triggerEventHandler('focus', {});
                     fixture.detectChanges();
                     UIInteractions.simulateTyping('11/10/2015', startInput);
@@ -1138,7 +1139,7 @@ describe('IgxDateRangePicker', () => {
                     tick(DEBOUNCE_TIME);
                     fixture.detectChanges();
                     const rangePicker = fixture.componentInstance.dateRange;
-                    expect((rangePicker as any).calendar.selectedDates.length).toBe(0);
+                    expect((rangePicker as any).calendar.selectedDates.length).toBe(1);
 
                     calendar = document.getElementsByClassName(CSS_CLASS_CALENDAR)[0];
                     UIInteractions.triggerKeyDownEvtUponElem('Escape', calendar);

projects/igniteui-angular/src/lib/date-range-picker/date-range-picker.component.ts

@@ -977,16 +977,20 @@ export class IgxDateRangePickerComponent extends PickerBaseDirective
             return;
         }
         this._setDisabledDates();
-        const { minValue, maxValue } = this._getMinMaxDates();
 
         const range: Date[] = [];
-        if (this.value?.start && this.value?.end) {
+        if (this.value) {
             const _value = this.toRangeOfDates(this.value);
-            if (DateTimeUtil.greaterThanMaxValue(_value.start, _value.end)) {
-                this.swapEditorDates();
+            if (_value.start && _value.end) {
+                if (DateTimeUtil.greaterThanMaxValue(_value.start, _value.end)) {
+                    this.swapEditorDates();
+                }
             }
-            if (this.valueInRange(this.value, minValue, maxValue)) {
-                range.push(_value.start, _value.end);
+            if (_value.start) {
+                range.push(_value.start);
+            }
+            if (_value.end) {
+                range.push(_value.end);
             }
         }
 
@@ -1008,18 +1012,6 @@ export class IgxDateRangePickerComponent extends PickerBaseDirective
         }
     }
 
-    private valueInRange(value: DateRange, minValue?: Date, maxValue?: Date): boolean {
-        const _value = this.toRangeOfDates(value);
-        if (minValue && DateTimeUtil.lessThanMinValue(_value.start, minValue, false)) {
-            return false;
-        }
-        if (maxValue && DateTimeUtil.greaterThanMaxValue(_value.end, maxValue, false)) {
-            return false;
-        }
-
-        return true;
-    }
-
     private extractRange(selection: Date[]): DateRange {
         return {
             start: selection[0] || null,