ENH use ranges for MDY patterns

dhall/Types.dhall

@@ -25,7 +25,14 @@ let Weekday = < Mon | Tue | Wed | Thu | Fri | Sat | Sun >
 let RepeatPat =
       { rpStart : Natural, rpBy : Natural, rpRepeats : Optional Natural }
 
-let MDYPat = < Single : Natural | Multi : List Natural | Repeat : RepeatPat >
+let MDYPat =
+      < Single : Natural
+      | Multi : List Natural
+      | Repeat : RepeatPat
+      | After : Natural
+      | Before : Natural
+      | Between : { _between1 : Natural, _between2 : Natural }
+      >
 
 let ModPat =
       { Type =

dhall/common.dhall

@@ -4,7 +4,7 @@ let List/map =
 
 let T =
       ./Types.dhall
-        sha256:27c65b31fe1b0dd58ff03ec0a37648f586914c81b81e5f33d3eac5a465475f2b
+        sha256:10af13e592448321c1e298f55a1e924e77b7e64bd35512147e0952de1f3abcfb
 
 let nullSplit =
       \(a : T.SplitAcnt) ->

lib/Internal/Insert.hs

@@ -53,14 +53,16 @@ expandCronPat b CronPat {..} = concatEither3 yRes mRes dRes $ \ys ms ds ->
     yRes = case cronYear of
       Nothing -> return [yb0 .. yb1]
       Just pat -> do
-        ys <- expandMDYPat (fromIntegral yb1) pat
+        ys <- expandMDYPat (fromIntegral yb0) (fromIntegral yb1) pat
         return $ dropWhile (< yb0) $ fromIntegral <$> ys
     mRes = expandMD 12 cronMonth
     dRes = expandMD 31 cronDay
     (s, e) = expandBounds b
     (yb0, mb0, db0) = toGregorian s
     (yb1, mb1, db1) = toGregorian $ addDays (-1) e
-    expandMD lim = fmap (fromIntegral <$>) . maybe (return [1 .. lim]) (expandMDYPat lim)
+    expandMD lim =
+      fmap (fromIntegral <$>)
+        . maybe (return [1 .. lim]) (expandMDYPat 1 lim)
     expandW (OnDay x) = [fromEnum x]
     expandW (OnDays xs) = fromEnum <$> xs
     ws = maybe [] expandW cronWeekly
@@ -70,21 +72,24 @@ expandCronPat b CronPat {..} = concatEither3 yRes mRes dRes $ \ys ms ds ->
       | m `elem` [4, 6, 9, 11] && d > 30 = Nothing
       | otherwise = Just $ fromGregorian y m d
 
-expandMDYPat :: Natural -> MDYPat -> EitherErr [Natural]
-expandMDYPat _ (Single x) = Right [x]
-expandMDYPat _ (Multi xs) = Right xs
-expandMDYPat lim (Repeat RepeatPat {rpStart = s, rpBy = b, rpRepeats = r})
+expandMDYPat :: Natural -> Natural -> MDYPat -> EitherErr [Natural]
+expandMDYPat lower upper (Single x) = Right [x | lower <= x && x <= upper]
+expandMDYPat lower upper (Multi xs) = Right $ dropWhile (<= lower) $ takeWhile (<= upper) xs
+expandMDYPat lower upper (After x) = Right [max lower x .. upper]
+expandMDYPat lower upper (Before x) = Right [lower .. min upper x]
+expandMDYPat lower upper (Between x y) = Right [max lower x .. min upper y]
+expandMDYPat lower upper (Repeat RepeatPat {rpStart = s, rpBy = b, rpRepeats = r})
   | b < 1 = Left $ PatternError s b r ZeroLength
   | otherwise = do
       k <- limit r
-      return $ takeWhile (<= k) [s + i * b | i <- [0 ..]]
+      return $ dropWhile (<= lower) $ takeWhile (<= k) [s + i * b | i <- [0 ..]]
   where
-    limit Nothing = Right lim
+    limit Nothing = Right upper
     limit (Just n)
       -- this guard not only produces the error for the user but also protects
       -- from an underflow below it
       | n < 1 = Left $ PatternError s b r ZeroRepeats
-      | otherwise = Right $ min (s + b * (n - 1)) lim
+      | otherwise = Right $ min (s + b * (n - 1)) upper
 
 dayToWeekday :: Day -> Int
 dayToWeekday (ModifiedJulianDay d) = mod (fromIntegral d + 2) 7