From 01fc9b45116f7ad6ddc56c7fb1535dec798c2b3a Mon Sep 17 00:00:00 2001
From: Liam DeBeasi <liamdebeasi@users.noreply.github.com>
Date: Mon, 28 Aug 2023 08:39:19 -0500
Subject: [PATCH] fix(datetime): gracefully handle invalid min/max (#28054)

Issue number: resolves #28041

---------

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issue. -->

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etc). Submit multiple pull requests if needed. -->

## What is the current behavior?
<!-- Please describe the current behavior that you are modifying. -->

`parseDate` returns `undefined` when given an invalid value. However,
our min/max processing functions did not account for this. As a result,
we would attempt to destructure an undefined value which resulted in an
error.

Note regarding linked issue: The developer is calling
`setMin(undefined)`. However, this is triggering a React quirk with
Custom Elements where `undefined` is being set to `null` inside of
React. The type signature on min/max is `string | undefined`, so `null`
is being treated as an invalid date value.

## What is the new behavior?
<!-- Please describe the behavior or changes that are being added by
this PR. -->

- Min/Max processing functions now return `undefined` if the input was
invalid.

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

<!-- If this introduces a breaking change, please describe the impact
and migration path for existing applications below. -->


## Other information

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screenshots of how the component looks before and after the change. -->

Dev build: `7.3.2-dev.11692887667.1614d10a`
---
 .../components/datetime/test/parse.spec.ts    | 24 +++++++++++++++++
 core/src/components/datetime/utils/parse.ts   | 26 ++++++++++++++++---
 2 files changed, 46 insertions(+), 4 deletions(-)

diff --git a/core/src/components/datetime/test/parse.spec.ts b/core/src/components/datetime/test/parse.spec.ts
index 282ec75a42..ea2e5132b0 100644
--- a/core/src/components/datetime/test/parse.spec.ts
+++ b/core/src/components/datetime/test/parse.spec.ts
@@ -154,6 +154,18 @@ describe('parseMinParts()', () => {
       minute: 30,
     });
   });
+  it('should return undefined when given invalid info', () => {
+    const today = {
+      day: 14,
+      month: 3,
+      year: 2022,
+      minute: 4,
+      hour: 2,
+    };
+    expect(parseMinParts(undefined, today)).toEqual(undefined);
+    expect(parseMinParts(null, today)).toEqual(undefined);
+    expect(parseMinParts('foo', today)).toEqual(undefined);
+  });
 });
 
 describe('parseMaxParts()', () => {
@@ -205,4 +217,16 @@ describe('parseMaxParts()', () => {
       minute: 59,
     });
   });
+  it('should return undefined when given invalid info', () => {
+    const today = {
+      day: 14,
+      month: 3,
+      year: 2022,
+      minute: 4,
+      hour: 2,
+    };
+    expect(parseMaxParts(undefined, today)).toEqual(undefined);
+    expect(parseMaxParts(null, today)).toEqual(undefined);
+    expect(parseMaxParts('foo', today)).toEqual(undefined);
+  });
 });
diff --git a/core/src/components/datetime/utils/parse.ts b/core/src/components/datetime/utils/parse.ts
index fda79085ac..04cd521310 100644
--- a/core/src/components/datetime/utils/parse.ts
+++ b/core/src/components/datetime/utils/parse.ts
@@ -132,8 +132,17 @@ export const parseAmPm = (hour: number) => {
  * For example, max="2012" would fill in the missing
  * month, day, hour, and minute information.
  */
-export const parseMaxParts = (max: string, todayParts: DatetimeParts): DatetimeParts => {
-  const { month, day, year, hour, minute } = parseDate(max);
+export const parseMaxParts = (max: string, todayParts: DatetimeParts): DatetimeParts | undefined => {
+  const result = parseDate(max);
+
+  /**
+   * If min was not a valid date then return undefined.
+   */
+  if (result === undefined) {
+    return;
+  }
+
+  const { month, day, year, hour, minute } = result;
 
   /**
    * When passing in `max` or `min`, developers
@@ -168,8 +177,17 @@ export const parseMaxParts = (max: string, todayParts: DatetimeParts): DatetimeP
  * For example, min="2012" would fill in the missing
  * month, day, hour, and minute information.
  */
-export const parseMinParts = (min: string, todayParts: DatetimeParts): DatetimeParts => {
-  const { month, day, year, hour, minute } = parseDate(min);
+export const parseMinParts = (min: string, todayParts: DatetimeParts): DatetimeParts | undefined => {
+  const result = parseDate(min);
+
+  /**
+   * If min was not a valid date then return undefined.
+   */
+  if (result === undefined) {
+    return;
+  }
+
+  const { month, day, year, hour, minute } = result;
 
   /**
    * When passing in `max` or `min`, developers