feat(datetime): add animation to adjacent days selection

core/src/components/datetime/datetime.ios.scss

@@ -251,7 +251,8 @@
  * is selected should have ion-color for
  * text color and be bolder.
  */
-:host .calendar-day.calendar-day-active {
+:host .calendar-day.calendar-day-active,
+:host .calendar-day.calendar-day-adjacent-day.calendar-day-active {
   color: current-color(base);
 
   font-weight: 600;

core/src/components/datetime/datetime.md.scss

@@ -117,7 +117,8 @@
  * is selected should have ion-color for
  * text color and be bolder.
  */
-:host .calendar-day.calendar-day-active {
+:host .calendar-day.calendar-day-active,
+:host .calendar-day.calendar-day-adjacent-day.calendar-day-active {
   color: current-color(contrast);
 }
 

core/src/components/datetime/datetime.tsx

@@ -2383,35 +2383,24 @@ export class Datetime implements ComponentInterface {
                     if (isAdjacentDay) {
                       // The user selected a day outside the current month. Ignore this button, as the month will be re-rendered.
                       this.el.blur();
-                    }
-
-                    this.setWorkingParts({
-                      ...this.workingParts,
-                      month: _month,
-                      day,
-                      year: _year,
-                      isAdjacentDay,
-                    });
-
-                    // multiple only needs date info, so we can wipe out other fields like time
-                    if (multiple) {
-                      this.setActiveParts(
-                        {
-                          month: _month,
-                          day,
-                          year: _year,
-                          isAdjacentDay,
-                        },
-                        isActive
-                      );
+                      this.activeParts = { ...activePart, ...referenceParts };
+                      this.animateToDate(referenceParts);
+                      this.confirm();
                     } else {
-                      this.setActiveParts({
-                        ...activePart,
-                        month: _month,
-                        day,
-                        year: _year,
-                        isAdjacentDay,
+                      this.setWorkingParts({
+                        ...this.workingParts,
+                        ...referenceParts,
                       });
+
+                      // multiple only needs date info, so we can wipe out other fields like time
+                      if (multiple) {
+                        this.setActiveParts(referenceParts, isActive);
+                      } else {
+                        this.setActiveParts({
+                          ...activePart,
+                          ...referenceParts,
+                        });
+                      }
                     }
                   }}
                 >

core/src/components/datetime/test/show-adjacent-days/datetime.e2e.ts

@@ -47,5 +47,75 @@ configs({ directions: ['ltr'] }).forEach(({ title, screenshot, config }) => {
       const datetime = page.locator('#display');
       await expect(datetime).toHaveScreenshot(screenshot(`datetime-show-adjacent-days-display`));
     });
+
+    test('should return the same date format on current month days and on adjacent days', async ({ page }) => {
+      await page.setContent(
+        `
+        <ion-datetime show-adjacent-days="true" value="2022-10-14T16:22:00.000Z" presentation="date"></ion-datetime>
+      `,
+        config
+      );
+
+      // Wait for the datetime to be ready.
+      await page.locator('.datetime-ready').waitFor();
+
+      const ionChange = await page.spyOnEvent('ionChange');
+
+      const calendarMonthYear = page.locator('ion-datetime .calendar-month-year');
+
+      /**
+       * Make sure to exclude adjacent days from the query since
+       * the previous/next month is rendered hidden. This causes
+       * the query to possibly return different results: one for
+       * the current month and one from the hidden previous/next
+       * month.
+       */
+      const october20Button = page.locator(
+        '[data-month="10"][data-year="2022"][data-day="20"]:not(.calendar-day-adjacent-day)'
+      );
+
+      await october20Button.click();
+
+      await ionChange.next();
+      await expect(ionChange).toHaveReceivedEventDetail({
+        value: '2022-10-20T16:22:00',
+      });
+
+      const november1Button = page.locator(
+        '.calendar-day-adjacent-day[data-month="11"][data-year="2022"][data-day="1"]'
+      );
+
+      await november1Button.click();
+      // Wait for the datetime to change the month since an adjacent day
+      // was clicked.
+      await page.waitForChanges();
+
+      // Wait for the title to update to the new month since it changes
+      // after the month animation finishes.
+      await expect(calendarMonthYear).toHaveText('November 2022');
+
+      await ionChange.next();
+      await expect(ionChange).toHaveReceivedEventDetail({
+        value: '2022-11-01T16:22:00',
+      });
+
+      /**
+       * Make sure to exclude adjacent days from the query since
+       * the previous/next month is rendered hidden. This causes
+       * the query to possibly return different results: one for
+       * the current month and one from the hidden previous/next
+       * month.
+       */
+      const november22Button = page.locator(
+        '[data-month="11"][data-year="2022"][data-day="22"]:not(.calendar-day-adjacent-day)'
+      );
+
+      await november22Button.click();
+
+      await ionChange.next();
+      await expect(ionChange).toHaveReceivedEventDetail({
+        value: '2022-11-22T16:22:00',
+      });
+    });
   });
 });

core/src/components/datetime/test/show-adjacent-days/index.html

@@ -178,6 +178,14 @@ <h2>Change firstDayOfWeek</h2>
           <br /><br />
           <ion-datetime show-adjacent-days="true" id="display" value="2022-02-22T16:30:00"></ion-datetime>
         </div>
+
+        <ion-datetime
+          id="default2"
+          show-adjacent-days="true"
+          locale="en-US"
+          value="2022-10-14T16:22:00.000Z"
+          presentation="date"
+        ></ion-datetime>
       </ion-content>
     </ion-app>
 
@@ -305,6 +313,11 @@ <h2>Change firstDayOfWeek</h2>
       };
 
       initCalendarMonthChangeObserver();
+
+      const datetimeDefault = document.querySelector('#default2');
+      datetimeDefault.addEventListener('ionChange', (ev) => {
+        console.log(ev.target.value);
+      });
     </script>
   </body>
 </html>