add instances of Typeable and Data to types, with test (#123)

lib/Data/Time/Calendar/Week.hs

@@ -5,6 +5,7 @@ module Data.Time.Calendar.Week
     , dayOfWeek
     ) where
 
+import Data.Data
 import Data.Time.Calendar.Days
 
 data DayOfWeek
@@ -15,7 +16,7 @@ data DayOfWeek
     | Friday
     | Saturday
     | Sunday
-    deriving (Eq, Show, Read)
+    deriving (Eq, Show, Read, Data, Typeable)
 
 -- | \"Circular\", so for example @[Tuesday ..]@ gives an endless sequence.
 -- Also: 'fromEnum' gives [1 .. 7] for [Monday .. Sunday], and 'toEnum' performs mod 7 to give a cycle of days.

lib/Data/Time/Clock/Internal/SystemTime.hs

@@ -8,6 +8,7 @@ module Data.Time.Clock.Internal.SystemTime
     , getTAISystemTime
     ) where
 
+import Data.Data
 import Control.DeepSeq
 import Data.Int (Int64)
 import Data.Time.Clock.Internal.DiffTime
@@ -31,7 +32,7 @@ import Foreign.C.Types (CLong(..))
 data SystemTime = MkSystemTime
     { systemSeconds :: {-# UNPACK #-}!Int64
     , systemNanoseconds :: {-# UNPACK #-}!Word32
-    } deriving (Eq, Ord, Show)
+    } deriving (Eq, Ord, Show, Data, Typeable)
 
 instance NFData SystemTime where
     rnf a = a `seq` ()

test/main/Main.hs

 module Main where
 
+import Test.Types()
 import Test.Calendar.AddDays
 import Test.Calendar.Calendars
 import Test.Calendar.ClipDates

test/main/Test/Types.hs

+module Test.Types(CheckInstances) where
+
+import Data.Data
+import Data.Time
+import Data.Time.Clock.System
+import Data.Time.Clock.TAI
+
+class (Typeable t, Data t) => CheckDataInstances t
+class (Typeable t, Data t, Eq t) => CheckInstances t
+
+instance CheckInstances UTCTime
+instance CheckInstances NominalDiffTime
+
+instance CheckInstances Day
+instance CheckInstances DayOfWeek
+instance CheckInstances TimeOfDay
+instance CheckInstances LocalTime
+instance CheckInstances TimeZone
+instance CheckDataInstances ZonedTime
+instance CheckInstances CalendarDiffDays
+instance CheckInstances CalendarDiffTime
+
+instance CheckInstances SystemTime
+
+instance CheckInstances AbsoluteTime
+instance CheckInstances UniversalTime

time.cabal

@@ -139,6 +139,7 @@ test-suite test-main
         tasty-quickcheck
     main-is: Main.hs
     other-modules:
+        Test.Types
         Test.TestUtil
         Test.Arbitrary
         Test.Calendar.AddDays