ADD: Add optional chrono feature for date/datetime conversions

[wtn]

Addresses #21.

Adds optional chrono feature flag that enables conversions from chrono date and datetime types to DateRange and DateTimeRange.

Changes

• Added chrono as an optional dependency (>=0.4.34, minimal features: alloc only)
• Implemented From traits for DateTimeRange:
  • Range<DateTime<Tz>> and RangeInclusive<DateTime<Tz>> (generic over timezone)
  • (DateTime<Tz>, DateTime<Tz>) tuple
  • (DateTime<Tz>, chrono::Duration) tuple
  • NaiveDate, Range<NaiveDate>, RangeInclusive<NaiveDate>, (NaiveDate, NaiveDate)
• Implemented From traits for DateRange:
  • NaiveDate, Range<NaiveDate>, RangeInclusive<NaiveDate>, (NaiveDate, NaiveDate)

Usage

[dependencies]
databento = { version = "0.37", features = ["chrono"] }

use chrono::{TimeZone, Utc};
use databento::historical::DateTimeRange;

let start = Utc.with_ymd_and_hms(2024, 3, 15, 9, 30, 0).unwrap();
let end = Utc.with_ymd_and_hms(2024, 3, 15, 16, 0, 0).unwrap();
let range = DateTimeRange::from(start..end);

Type of change

Please delete options that are not relevant.

• New feature (non-breaking change which adds functionality)

How has this change been tested?

• cargo test --features chrono chrono_tests - 14 new tests for chrono conversions
• ./scripts/test.sh - all 50 tests pass (includes chrono tests)
• cargo test (without chrono feature) - 36 existing tests still pass

Checklist

• My code builds locally with no new warnings (scripts/build.sh)
• My code follows the style guidelines (scripts/lint.sh and scripts/format.sh)
• New and existing unit tests pass locally with my changes (scripts/test.sh)
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works

Declaration

I confirm this contribution is made under an Apache 2.0 license and that I have the authority
necessary to make this contribution on behalf of its copyright owner.

[wtn]

@TheDan64 Is this feature still relevant for you?

[threecgreen]

Hi @wtn,
Thanks for opening the PR with tests!

In order to merge this, I'd want the chrono support to extend to Live with Subscription::start. You could probably repurpose the DateTimeLike trait that's currently in reference.rs for this purpose.

[wtn]

Thanks, addressed feedback and fixed the rustfmt error.

[threecgreen]

Committed in 6eb1d48. Thanks again!