Refactor DatePicker code for improved readability and consistency in range selection logic

Author: ilchenkoArtem

src/day.tsx

@@ -341,15 +341,19 @@ export default class Day extends Component<DayProps> {
       return false;
     }
 
-    const { day, startDate, selectsStart, swapRange, selectsRange } = this.props;
+    const { day, startDate, selectsStart, swapRange, selectsRange } =
+      this.props;
     const selectingDate = this.props.selectingDate ?? this.props.preSelection;
 
     if (selectsStart) {
       return isSameDay(day, selectingDate);
     }
 
     if (selectsRange && swapRange && startDate && selectingDate) {
-      return isSameDay(day, isBefore(selectingDate, startDate) ? selectingDate : startDate);
+      return isSameDay(
+        day,
+        isBefore(selectingDate, startDate) ? selectingDate : startDate,
+      );
     }
 
     return isSameDay(day, startDate);
@@ -360,15 +364,19 @@ export default class Day extends Component<DayProps> {
       return false;
     }
 
-    const { day, endDate, selectsEnd, selectsRange, swapRange, startDate } = this.props;
+    const { day, endDate, selectsEnd, selectsRange, swapRange, startDate } =
+      this.props;
     const selectingDate = this.props.selectingDate ?? this.props.preSelection;
 
     if (selectsEnd) {
       return isSameDay(day, selectingDate);
     }
 
     if (selectsRange && swapRange && startDate && selectingDate) {
-      return isSameDay(day, isBefore(selectingDate, startDate) ? startDate : selectingDate);
+      return isSameDay(
+        day,
+        isBefore(selectingDate, startDate) ? startDate : selectingDate,
+      );
     }
 
     if (selectsRange) {

src/test/day_test.test.tsx

@@ -914,7 +914,7 @@ describe("Day", () => {
             .querySelector(".react-datepicker__day")
             ?.classList.contains(rangeDayClassName),
         ).toBe(true);
-      })
+      });
 
       it("should select range from selectingDate to startDate if selectingDate is before startDate", () => {
         const startDate = newDate();
@@ -936,7 +936,7 @@ describe("Day", () => {
 
       it("should select as range if selectingDate is equal to startDate", () => {
         const startDate = newDate();
-        const selectingDate = startDate
+        const selectingDate = startDate;
 
         const containerStartDay = renderDay(startDate, {
           startDate,
@@ -967,7 +967,6 @@ describe("Day", () => {
             ?.classList.contains(rangeDayStartClassName),
         ).toBe(true);
 
-
         const containerEndDay = renderDay(startDate, {
           startDate,
           selectingDate,
@@ -980,7 +979,7 @@ describe("Day", () => {
             .querySelector(".react-datepicker__day")
             ?.classList.contains(rangeDayEndClassName),
         ).toBe(true);
-      })
+      });
 
       it("should set selectingDate as the end of range and startDate as the start of range if selectingDate is after startDate", () => {
         const startDate = newDate();
@@ -1010,9 +1009,9 @@ describe("Day", () => {
             .querySelector(".react-datepicker__day")
             ?.classList.contains(rangeDayEndClassName),
         ).toBe(true);
-      })
+      });
 
-      it('should set startDate as the end and start range if selectionDate equal startDate', () => {
+      it("should set startDate as the end and start range if selectionDate equal startDate", () => {
         const startDate = newDate();
         const selectingDate = startDate;
 
@@ -1041,7 +1040,7 @@ describe("Day", () => {
             ?.classList.contains(rangeDayEndClassName),
         ).toBe(true);
       });
-    })
+    });
   });
 
   describe("today", () => {