Open Radar

 
Summary:
NSDateComponentsFormatter works incorrectly if difference between dates approx 1 day

Steps to Reproduce:
Add to playground code:

let formatter = NSDateComponentsFormatter()
formatter.unitsStyle = .Short
formatter.maximumUnitCount = 1
formatter.allowedUnits = [.Year, .Month, .Day, .Hour, .Minute, .Second]

let df = NSDateFormatter()
df.dateFormat = "yyyy-MM-dd HH:mm:ss zzz"

let from = df.dateFromString("2016-05-17 12:10:00 UTC")!
let to1 = df.dateFromString("2016-05-18 13:00:32 UTC")!
let timestamp1 = formatter.stringFromDate(from, toDate: to1)!
print(timestamp1) //"1 day, 1 hr" but it is approx 1 day and 50 min

let to2 = df.dateFromString("2016-05-18 13:20:06 UTC")!
let timestamp2 = formatter.stringFromDate(from, toDate: to2)!
print(timestamp2) //"1 day" but it is approx 1 day and 70 min


Expected Results:
For both cases "1 day" should be printed

Actual Results:
We can see two problems here
1) 2 components are returned "1 day, 1 hr", but formatter.maximumUnitCount = 1
2) For greater difference 1 day and 70 min we have "1 day" result, but for smaller 1 day and 50 min difference we have greater result "1 day, 1 hr"
1 day and 70 min > 1 day and 50 min, but "1 day" < "1 day, 1 hr"


Version:
iOS 9.3.1 (13E238)


Configuration:
iPhone 5s