date updates

[hardy925]

Fixes

Please link to the issue this PR addresses

Description

better ISO 8106 support

Proposed changes in this PR

Things to look at

• Test coverage
• Code Style
• Documentation (READMEs etc)

[ChrisDufourMB]

This doesn't appear to support all the different kinds of timezones that could be part of an ISO date, what degree of support are you looking to implement? I feel like we will need more tests cases for all the different variants and edge cases that can happen

Here is the test I tried, for reference

test({
  name: "iso8601Date parses with added timezone - 2020-12-31T12:00:00Z-06:00",
  fn() {
    const testJson = `{"date":"2020-12-31T06:00:00Z-06:00"}`;
    const testObj = JSON.parse(testJson, (_, v) => iso8601Date(v));
    assert(testObj.date instanceof Date);
    assertEquals(testObj.date.toISOString(), "2020-12-31T12:00:00.000Z-06:00");
  },
});

[ms1111]

Would you also want to have a serializer in the library to render a local date as an ISO date string (YYYY-MM-DD) in toJson()? Or would you want apps to provide that themselves (like our localDateToIsoDateString() function)

Here's the test case for localDateToIsoDateString() btw:

    // 1990-12-11
    const localDateMidnight = new Date(1990, 11, 11);

expect(localDateToIsoDateString(localDateMidnight)).toEqual("1990-12-11");

code:

export function localDateToIsoDateString(date: Date): string {
    const year = date.getFullYear();
    const month = date.getMonth() + 1;
    const day = date.getDate();
    return `${formatISOYear(year)}-${padLeft(month, 2)}-${padLeft(day, 2)}`;
}

[hardy925]

@ms1111 I think we'll go the route of having authors write their strategies, the two we provide for dates is more than enough IMHO.