From 3a7f5f166ee8d8d7e1861313e2bc6f4856e4fbe9 Mon Sep 17 00:00:00 2001
From: Liam DeBeasi <liamdebeasi@users.noreply.github.com>
Date: Tue, 19 Jul 2022 16:41:27 -0400
Subject: [PATCH] fix(datetime): account for previous years with preferWheel
 (#25656)

---
 .../test/prefer-wheel/datetime.e2e.ts         | 34 ++++++++++++++++
 core/src/components/datetime/utils/data.ts    | 39 +++++++++++++++----
 2 files changed, 66 insertions(+), 7 deletions(-)

diff --git a/core/src/components/datetime/test/prefer-wheel/datetime.e2e.ts b/core/src/components/datetime/test/prefer-wheel/datetime.e2e.ts
index 2326d87fce4..3072c7fc039 100644
--- a/core/src/components/datetime/test/prefer-wheel/datetime.e2e.ts
+++ b/core/src/components/datetime/test/prefer-wheel/datetime.e2e.ts
@@ -198,6 +198,23 @@ test.describe('datetime: prefer wheel', () => {
 
       expect(dateValues).toHaveText(['2月1日(火)', '2月2日(水)', '2月3日(木)']);
     });
+    test('should respect min and max bounds even across years', async ({ page }) => {
+      await page.setContent(`
+        <ion-datetime
+          presentation="date-time"
+          prefer-wheel="true"
+          value="2022-02-01"
+          min="2021-12-01"
+          max="2023-01-01"
+        ></ion-datetime>
+      `);
+
+      await page.waitForSelector('.datetime-ready');
+
+      const dateValues = page.locator('.date-column .picker-item:not(.picker-item-empty)');
+
+      expect(await dateValues.count()).toBe(427);
+    });
   });
   test.describe('datetime: time-date wheel rendering', () => {
     test('should not have visual regressions', async ({ page }) => {
@@ -286,5 +303,22 @@ test.describe('datetime: prefer wheel', () => {
 
       expect(dateValues).toHaveText(['2月1日(火)', '2月2日(水)', '2月3日(木)']);
     });
+    test('should respect min and max bounds even across years', async ({ page }) => {
+      await page.setContent(`
+        <ion-datetime
+          presentation="time-date"
+          prefer-wheel="true"
+          value="2022-02-01"
+          min="2021-12-01"
+          max="2023-01-01"
+        ></ion-datetime>
+      `);
+
+      await page.waitForSelector('.datetime-ready');
+
+      const dateValues = page.locator('.date-column .picker-item:not(.picker-item-empty)');
+
+      expect(await dateValues.count()).toBe(427);
+    });
   });
 });
diff --git a/core/src/components/datetime/utils/data.ts b/core/src/components/datetime/utils/data.ts
index c44831c0717..ed11abc0405 100644
--- a/core/src/components/datetime/utils/data.ts
+++ b/core/src/components/datetime/utils/data.ts
@@ -413,6 +413,19 @@ interface CombinedDateColumnData {
   items: PickerColumnItem[];
 }
 
+/**
+ * Given a starting date and an upper bound,
+ * this functions returns an array of all
+ * month objects in that range.
+ */
+const getAllMonthsInRange = (currentParts: DatetimeParts, maxParts: DatetimeParts): DatetimeParts[] => {
+  if (currentParts.month === maxParts.month && currentParts.year === maxParts.year) {
+    return [currentParts];
+  }
+
+  return [currentParts, ...getAllMonthsInRange(getNextMonth(currentParts), maxParts)];
+};
+
 /**
  * Creates and returns picker items
  * that represent the days in a month.
@@ -422,16 +435,28 @@ export const getCombinedDateColumnData = (
   locale: string,
   refParts: DatetimeParts,
   todayParts: DatetimeParts,
-  minParts?: DatetimeParts,
-  maxParts?: DatetimeParts,
+  minParts: DatetimeParts,
+  maxParts: DatetimeParts,
   dayValues?: number[],
   monthValues?: number[]
 ): CombinedDateColumnData => {
   let items: PickerColumnItem[] = [];
   let parts: DatetimeParts[] = [];
 
-  // TODO(FW-1693) This does not work when the previous month is in the previous year.
-  const months = getMonthColumnData(locale, refParts, minParts, maxParts, monthValues, { month: 'short' });
+  /**
+   * Get all month objects from the min date
+   * to the max date. Note: Do not use getMonthColumnData
+   * as that function only generates dates within a
+   * single year.
+   */
+  let months = getAllMonthsInRange(minParts, maxParts);
+
+  /**
+   * Filter out any disallowed month values.
+   */
+  if (monthValues) {
+    months = months.filter(({ month }) => monthValues.includes(month));
+  }
 
   /**
    * Get all of the days in the month.
@@ -440,7 +465,7 @@ export const getCombinedDateColumnData = (
    * of work as the text.
    */
   months.forEach((monthObject) => {
-    const referenceMonth = { month: monthObject.value as number, day: null, year: refParts.year };
+    const referenceMonth = { month: monthObject.month, day: null, year: refParts.year };
     const monthDays = getDayColumnData(locale, referenceMonth, minParts, maxParts, dayValues, {
       month: 'short',
       day: 'numeric',
@@ -459,7 +484,7 @@ export const getCombinedDateColumnData = (
        */
       dateColumnItems.push({
         text: isToday ? getTodayLabel(locale) : dayObject.text,
-        value: `${refParts.year}-${monthObject.value}-${dayObject.value}`,
+        value: `${refParts.year}-${monthObject.month}-${dayObject.value}`,
       });
 
       /**
@@ -473,7 +498,7 @@ export const getCombinedDateColumnData = (
        * updating the picker column value.
        */
       dateParts.push({
-        month: monthObject.value as number,
+        month: monthObject.month,
         year: refParts.year,
         day: dayObject.value as number,
       });