Add Linux support to SwiftDate

[icyield]

5.0.5 does not compile under Linux. Multiple issues objective C runtimes, arc_random etc.

[mikecsh]

Is there any specific version known to compile under Linux?

[malcommac]

Is there an easy way to test it? A container?

[vzsg]

Sure there is. Install Docker for Mac CE, and run this from your project folder:

docker run --rm -it -w /app -v `pwd`:/app swift:4.2 swift build

After a cursory look (a friend is looking for working date arithmetics on Linux and found this project, I'm just helping out), the project doesn't build because there are multiple Darwin-only references in it, plus the unit tests are not set up correctly either.

(Travis can be potentially tamed to do Linux testing too, once the source and the tests are up to speed. As a side note, I've had more luck with CircleCI 2.0 for Swift + Linux.)

[malcommac]

Did you know if this error is referred to the git repository or...what?

danielembp15:SwiftDate daniele$ docker run --rm -it -w /app -v `pwd`:/app swift:4.2 swift build
docker: invalid reference format: repository name must be lowercase.
See 'docker run --help'.
danielembp15:SwiftDate daniele$ 

[vzsg]

Do you have any spaces in your current working directory path? My gut feeling says that it might cause trouble with the backticks.

[malcommac]

Yeah it was related to spaces in path. With iCloud it's a damn mess. Thanks.

[malcommac]

Related commit: #611 Removed arc4random_uniform to use new Swift 4.2 random APIs.

[malcommac]

This is the opening issues on Linux, strictly related to CFCalendar and CFCalendarUnit which should be available on CoreFoundation for Linux.
It's a bit strange.

danielembp15:SwiftDate daniele$ docker run --rm -it -w /app -v `pwd`:/app swift:4.2 swift build
Compile Swift Module 'SwiftDate' (158 sources)
/app/Sources/SwiftDate/Supports/Commons.swift:179:21: error: use of undeclared type 'CFCalendar'
        typealias CFType = CFCalendar
                           ^~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:226:25: error: use of undeclared type 'CFCalendarUnit'
        internal var _cfValue: CFCalendarUnit? {
                               ^~~~~~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:208:14: error: use of undeclared type 'CFAbsoluteTime'
                var start: CFAbsoluteTime = 0.0
                           ^~~~~~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:209:11: error: use of undeclared type 'CFTimeInterval'
                var ti: CFTimeInterval = 0.0
                        ^~~~~~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:212:12: error: use of unresolved identifier 'CFCalendarGetTimeRangeOfUnit'
                                return CFCalendarGetTimeRangeOfUnit(_cfObject, cfValue, date.timeIntervalSinceReferenceDate, startp, tip)
                                       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:243:24: error: use of unresolved identifier 'CFCalendarUnit'
                case .day:                              return CFCalendarUnit.day.rawValue
                                                               ^~~~~~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:244:24: error: use of unresolved identifier 'CFCalendarUnit'
                case .era:                              return CFCalendarUnit.era.rawValue
                                                               ^~~~~~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:245:25: error: use of unresolved identifier 'CFCalendarUnit'
                case .year:                             return CFCalendarUnit.year.rawValue
                                                               ^~~~~~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:246:25: error: use of unresolved identifier 'CFCalendarUnit'
                case .month:                    return CFCalendarUnit.month.rawValue
                                                       ^~~~~~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:247:25: error: use of unresolved identifier 'CFCalendarUnit'
                case .hour:                             return CFCalendarUnit.hour.rawValue
                                                               ^~~~~~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:248:26: error: use of unresolved identifier 'CFCalendarUnit'
                case .minute:                   return CFCalendarUnit.minute.rawValue
                                                       ^~~~~~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:249:26: error: use of unresolved identifier 'CFCalendarUnit'
                case .second:                   return CFCalendarUnit.second.rawValue
                                                       ^~~~~~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:250:27: error: use of unresolved identifier 'CFCalendarUnit'
                case .weekday:                  return CFCalendarUnit.weekday.rawValue
                                                       ^~~~~~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:251:32: error: use of unresolved identifier 'CFCalendarUnit'
                case .weekdayOrdinal:   return CFCalendarUnit.weekdayOrdinal.rawValue
                                               ^~~~~~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:252:27: error: use of unresolved identifier 'CFCalendarUnit'
                case .quarter:                  return CFCalendarUnit.quarter.rawValue
                                                       ^~~~~~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:253:30: error: use of unresolved identifier 'CFCalendarUnit'
                case .weekOfMonth:              return CFCalendarUnit.weekOfMonth.rawValue
                                                       ^~~~~~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:254:29: error: use of unresolved identifier 'CFCalendarUnit'
                case .weekOfYear:               return CFCalendarUnit.weekOfYear.rawValue
                                                       ^~~~~~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:255:34: error: use of unresolved identifier 'CFCalendarUnit'
                case .yearForWeekOfYear:return CFCalendarUnit.yearForWeekOfYear.rawValue
                                               ^~~~~~~~~~~~~~
/app/Sources/SwiftDate/Date/Date.swift:19:1: error: type 'Date' does not conform to protocol 'DateRepresentable'
extension Date: DateRepresentable {
^
/app/Sources/SwiftDate/DateRepresentable.swift:171:6: note: protocol requires property 'customFormatter' with type 'DateFormatter?'; do you want to add a stub?
        var customFormatter: DateFormatter? { get set }
            ^
error: terminated(1): /usr/bin/swift-build-tool -f /app/.build/debug.yaml main output:

[malcommac]

Still remains only the definitions inside the CFCalendarUnit enum.

danielembp15:SwiftDate daniele$ docker run --rm -it -w /app -v `pwd`:/app swift:4.2 swift build
Compile Swift Module 'SwiftDate' (158 sources)
/app/Sources/SwiftDate/Supports/Commons.swift:246:24: error: type 'CFCalendarUnit' (aka 'UInt') has no member 'day'
                case .day:                              return CFCalendarUnit.day.rawValue
                                                               ^~~~~~~~~~~~~~ ~~~
/app/Sources/SwiftDate/Supports/Commons.swift:247:24: error: type 'CFCalendarUnit' (aka 'UInt') has no member 'era'
                case .era:                              return CFCalendarUnit.era.rawValue
                                                               ^~~~~~~~~~~~~~ ~~~
/app/Sources/SwiftDate/Supports/Commons.swift:248:25: error: type 'CFCalendarUnit' (aka 'UInt') has no member 'year'
                case .year:                             return CFCalendarUnit.year.rawValue
                                                               ^~~~~~~~~~~~~~ ~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:249:25: error: type 'CFCalendarUnit' (aka 'UInt') has no member 'month'
                case .month:                    return CFCalendarUnit.month.rawValue
                                                       ^~~~~~~~~~~~~~ ~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:250:25: error: type 'CFCalendarUnit' (aka 'UInt') has no member 'hour'
                case .hour:                             return CFCalendarUnit.hour.rawValue
                                                               ^~~~~~~~~~~~~~ ~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:251:26: error: type 'CFCalendarUnit' (aka 'UInt') has no member 'minute'
                case .minute:                   return CFCalendarUnit.minute.rawValue
                                                       ^~~~~~~~~~~~~~ ~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:252:26: error: type 'CFCalendarUnit' (aka 'UInt') has no member 'second'
                case .second:                   return CFCalendarUnit.second.rawValue
                                                       ^~~~~~~~~~~~~~ ~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:253:27: error: type 'CFCalendarUnit' (aka 'UInt') has no member 'weekday'
                case .weekday:                  return CFCalendarUnit.weekday.rawValue
                                                       ^~~~~~~~~~~~~~ ~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:254:32: error: type 'CFCalendarUnit' (aka 'UInt') has no member 'weekdayOrdinal'
                case .weekdayOrdinal:   return CFCalendarUnit.weekdayOrdinal.rawValue
                                               ^~~~~~~~~~~~~~ ~~~~~~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:255:27: error: type 'CFCalendarUnit' (aka 'UInt') has no member 'quarter'
                case .quarter:                  return CFCalendarUnit.quarter.rawValue
                                                       ^~~~~~~~~~~~~~ ~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:256:30: error: type 'CFCalendarUnit' (aka 'UInt') has no member 'weekOfMonth'
                case .weekOfMonth:              return CFCalendarUnit.weekOfMonth.rawValue
                                                       ^~~~~~~~~~~~~~ ~~~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:257:29: error: type 'CFCalendarUnit' (aka 'UInt') has no member 'weekOfYear'
                case .weekOfYear:               return CFCalendarUnit.weekOfYear.rawValue
                                                       ^~~~~~~~~~~~~~ ~~~~~~~~~~
/app/Sources/SwiftDate/Supports/Commons.swift:258:34: error: type 'CFCalendarUnit' (aka 'UInt') has no member 'yearForWeekOfYear'
                case .yearForWeekOfYear:return CFCalendarUnit.yearForWeekOfYear.rawValue

[malcommac]

Okay it now compiles fine. I've switched from old internal implementation taken from CoreFoundation to rangeOfUnit() of NSCalendar (see https://github.com/apple/swift-corelibs-foundation/blob/fa8a1c2afa4c322493a83272758c2e816e3b1b8b/Foundation/NSCalendar.swift#L420).

[malcommac]

Is there a way to run unit tests via docker?

[malcommac]

commands is

docker run --rm -v "$(pwd):/pkg" -w "/pkg" swift:4.2 /bin/bash -c "swift test --build-path ./.build/linux"

[malcommac]

Finally it compiles successfully.
LinuxMain.swift file with test can be generated from XCTest of XCode via the script generateLinuxTests.sh (it needs of sourcery tools brew install sourcery):

sourcery --sources Tests --templates .sourcery/LinuxMain.stencil --output .sourcery --force-parse generated
mv .sourcery/LinuxMain.generated.swift Tests/LinuxMain.swift

However there are several failed tests.

[malcommac]

I had a strange issue with compare function with granularity inside the NSCalendar object.

let d2 = Date.init(timeIntervalSince1970: 1529431200.0) // 2018-06-19 18:00:00 +0000
let d3 = Date.init(timeIntervalSince1970: 1529604000.0) // 2018-06-21 18:00:00 +0000
print("Data2: \(d2), Date3: \(d3)")
let res = Calendar.current.compare(d2, to: d3, toGranularity: .month)

The following code return .orderedSame on macOS/iOS (and test succeded), while on Linux it just return .orderedAscending (failing the test).

I had filled the following radar on Swift forum:
https://bugs.swift.org/browse/SR-9101

[malcommac]

Follow #612