From f82b5c18b82b5e6fd18c89b505fb65fdaac4732b Mon Sep 17 00:00:00 2001
From: Jorge del Casar <948953+jorgecasar@users.noreply.github.com>
Date: Tue, 15 Dec 2020 19:30:19 +0100
Subject: [PATCH] fix(calendar): solve previousMonth and nextMonth conditions
 error

---
 .changeset/curly-ladybugs-grab.md            |  5 ++++
 packages/calendar/src/LionCalendar.js        |  9 ++++--
 packages/calendar/test/lion-calendar.test.js | 31 +++++++++++++++++++-
 3 files changed, 41 insertions(+), 4 deletions(-)
 create mode 100644 .changeset/curly-ladybugs-grab.md

diff --git a/.changeset/curly-ladybugs-grab.md b/.changeset/curly-ladybugs-grab.md
new file mode 100644
index 000000000..65fc34108
--- /dev/null
+++ b/.changeset/curly-ladybugs-grab.md
@@ -0,0 +1,5 @@
+---
+'@lion/calendar': patch
+---
+
+solve previousMonth and nextMonth conditions error
diff --git a/packages/calendar/src/LionCalendar.js b/packages/calendar/src/LionCalendar.js
index 77cceff3e..7d707036f 100644
--- a/packages/calendar/src/LionCalendar.js
+++ b/packages/calendar/src/LionCalendar.js
@@ -515,9 +515,12 @@ export class LionCalendar extends LocalizeMixin(LitElement) {
     const day = createDay(new Date(_day.date), _day);
     const today = normalizeDateTime(new Date());
     day.central = isSameDate(day.date, this.centralDate);
-    day.previousMonth = currentMonth && day.date.getMonth() < currentMonth.getMonth();
-    day.currentMonth = currentMonth && day.date.getMonth() === currentMonth.getMonth();
-    day.nextMonth = currentMonth && day.date.getMonth() > currentMonth.getMonth();
+    const dayYearMonth = `${day.date.getFullYear()}${`0${day.date.getMonth() + 1}`.slice(-2)}`;
+    const currentYearMonth =
+      currentMonth && `${currentMonth.getFullYear()}${`0${currentMonth.getMonth() + 1}`.slice(-2)}`;
+    day.previousMonth = currentMonth && dayYearMonth < currentYearMonth;
+    day.currentMonth = currentMonth && dayYearMonth === currentYearMonth;
+    day.nextMonth = currentMonth && dayYearMonth > currentYearMonth;
     day.selected = this.selectedDate ? isSameDate(day.date, this.selectedDate) : false;
     day.past = day.date < today;
     day.today = isSameDate(day.date, today);
diff --git a/packages/calendar/test/lion-calendar.test.js b/packages/calendar/test/lion-calendar.test.js
index 5ebaa268a..700a944e8 100644
--- a/packages/calendar/test/lion-calendar.test.js
+++ b/packages/calendar/test/lion-calendar.test.js
@@ -1206,7 +1206,6 @@ describe('<lion-calendar>', () => {
           `),
         );
         const { previousMonthDayObjs, nextMonthDayObjs } = elObj;
-
         expect(previousMonthDayObjs.length).to.equal(3);
         expect(previousMonthDayObjs[0].cellIndex).to.equal(0);
         expect(previousMonthDayObjs[0].monthday).to.equal(29);
@@ -1222,6 +1221,36 @@ describe('<lion-calendar>', () => {
         expect(nextMonthDayObjs[1].monthday).to.equal(2);
       });
 
+      it('renders days for next months in the last month of the year', async () => {
+        const elObj = new CalendarObject(
+          await fixture(html`
+            <lion-calendar .selectedDate="${new Date('2020/12/12')}"></lion-calendar>
+          `),
+        );
+        const { nextMonthDayObjs } = elObj;
+        expect(nextMonthDayObjs.length).to.equal(2);
+        expect(nextMonthDayObjs[0].cellIndex).to.equal(5);
+        expect(nextMonthDayObjs[0].monthday).to.equal(1);
+        expect(nextMonthDayObjs[1].cellIndex).to.equal(6);
+        expect(nextMonthDayObjs[1].monthday).to.equal(2);
+      });
+
+      it('renders days for previous months in the first month of the year', async () => {
+        const elObj = new CalendarObject(
+          await fixture(html`
+            <lion-calendar .selectedDate="${new Date('2020/01/12')}"></lion-calendar>
+          `),
+        );
+        const { previousMonthDayObjs } = elObj;
+        expect(previousMonthDayObjs.length).to.equal(3);
+        expect(previousMonthDayObjs[0].cellIndex).to.equal(0);
+        expect(previousMonthDayObjs[0].monthday).to.equal(29);
+        expect(previousMonthDayObjs[1].cellIndex).to.equal(1);
+        expect(previousMonthDayObjs[1].monthday).to.equal(30);
+        expect(previousMonthDayObjs[2].cellIndex).to.equal(2);
+        expect(previousMonthDayObjs[2].monthday).to.equal(31);
+      });
+
       it('sets aria-current="date" to todays button', async () => {
         const elObj = new CalendarObject(await fixture(html`<lion-calendar></lion-calendar>`));
         const hasAriaCurrent = /** @param {DayObject} d */ d =>