fix(date-picker): fix AM/PM display incorrect issue when switching ho…

…urs (#1822)

src/Calendar/TimeDropdown.tsx

@@ -111,13 +111,12 @@ class TimeDropdown extends React.PureComponent<TimeDropdownProps> {
   };
 
   handleClick = (type: TimeType, d: number, event: React.MouseEvent) => {
-    const { onSelect, date } = this.props;
-    // $FlowFixMe
+    const { onSelect, date, showMeridian } = this.props;
     let nextDate = date || new Date();
 
     switch (type) {
       case 'hours':
-        nextDate = setHours(date, d);
+        nextDate = setHours(date, showMeridian && getHours(nextDate) >= 12 ? d + 12 : d);
         break;
       case 'minutes':
         nextDate = setMinutes(date, d);

src/DatePicker/test/DatePickerSpec.js

@@ -293,4 +293,24 @@ describe('DatePicker', () => {
     );
     assert.equal(picker.querySelector('.rs-calendar-time-dropdown-column li').innerText, '12');
   });
+
+  it('Should keep AM PM unchanged', () => {
+    const instance = getInstance(
+      <DatePicker
+        value={parse('2017-08-14 13:00:00')}
+        format="hh:mm:ss A"
+        defaultOpen
+        showMeridian
+      />
+    );
+
+    const picker = instance.menuContainerRef.current;
+
+    assert.equal(picker.querySelector('.rs-calendar-header-title-time').innerText, '01:00:00');
+
+    ReactTestUtils.Simulate.click(picker.querySelector('.rs-calendar-time-dropdown-cell'));
+
+    assert.equal(picker.querySelector('.rs-calendar-header-meridian').innerText, 'PM');
+    assert.equal(picker.querySelector('.rs-calendar-header-title-time').innerText, '12:00:00');
+  });
 });