Duration using decimal hours produces wrong output using toFormat #1070

luxon_bug.md

Describe the bug

Creating a duration using a decimal hour then using toFormat produces an incorrect result

The inputs we've seen wrong so far are 2.4 and 5.3

To Reproduce

luxon.Duration.fromObject({hour: 2.4}).toFormat('hh:mm') returns "02:23"
luxon.Duration.fromObject({hour: 5.3}).toFormat('hh:mm') returns "05:17"

Actual vs Expected behavior

• 2.4 hours is 02:24
• 5.3 hours is 05:18

Additional context

Converting to different units from hours produces correct results

luxon.Duration.fromObject({minute: 2.4 * 60}).toFormat('hh:mm') = "02:24"
luxon.Duration.fromObject({second: 2.4 * 60 * 60}).toFormat('hh:mm') = "02:24"
luxon.Duration.fromObject({hour: 2.4}).shiftTo('seconds').toFormat('hh:mm') = "02:24"

Shifting to hours also produces the wrong result

luxon.Duration.fromObject({minute: 2.4 * 60}).shiftTo('hour').toFormat('hh:mm') = "02:23"

The durations still produce the same valueOf

luxon.Duration.fromObject({hour: 2.4}).valueOf() = 8640000
luxon.Duration.fromObject({minute: 2.4 * 60}).valueOf() = 8640000

Instructions

1. Clone the library repository to your local development environment: https://github.com/moment/luxon
2. Checkout to tag 2.1.1