DateComponentsFormatter maximumUnitCount is not respected for all dates

Number:rdar://36674487 Date Originated:1/19/2018
Status:Open Resolved:
Product:iOS + SDK Product Version:iOS 11.2.2
Classification:Other Bug Reproducible:

When initializing a DateComponentsFormatter with a maximum unit count of 1, dates that have the next unit that should be truncated with a value of 1 sometimes output with two units.

e.g.: "3 minutes 1 second", "6 hours 1 minute", "4 days, 1 hour", etc.

Steps to Reproduce:
Repro case available in attached playground and screenshot.

Expected Results:
When a DateComponentsFormatter has maximumUnitCount set to 1, all output should have only one unit.

Actual Results:
Some outputs have two units.

iOS 11.2.2



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