New patches:

[Fix ticket 1762
David Benbennick <dbenbenn@gmail.com>**20071111201939] {
hunk ./Data/IntSet.hs 113
-import QuickCheck 
+import Test.QuickCheck 
hunk ./Data/IntSet.hs 116
+import qualified Data.Set as Set
hunk ./Data/IntSet.hs 171
+-- Invariant: The Mask is a power of 2.  It is the largest bit position at which
+--            two elements of the set differ.
+-- Invariant: Prefix is the common high-order bits that all elements share to
+--            the left of the Mask bit.
+-- Invariant: In Bin prefix mask left right, left consists of the elements that
+--            don't have the mask bit set; right is all the elements that do.
hunk ./Data/IntSet.hs 413
-  | shorter m2 m1  = subsetCmpLt
+  | shorter m2 m1  = case subsetCmpLt of
+                       GT -> GT
+                       _ -> LT
hunk ./Data/IntSet.hs 864
+-- Suppose a is largest such that 2^a divides 2*m.
+-- Then mask i m is i with the low a bits zeroed out.
hunk ./Data/IntSet.hs 1031
+
+{--------------------------------------------------------------------
+  Bin invariants
+--------------------------------------------------------------------}
+powersOf2 :: IntSet
+powersOf2 = fromList [2^i | i <- [0..63]]
+
+-- Check the invariant that the mask is a power of 2.
+prop_MaskPow2 :: IntSet -> Bool
+prop_MaskPow2 (Bin _ msk left right) = member msk powersOf2 && prop_MaskPow2 left && prop_MaskPow2 right
+prop_MaskPow2 _ = True
+
+-- Check that the prefix satisfies its invariant.
+prop_Prefix :: IntSet -> Bool
+prop_Prefix s@(Bin prefix msk left right) = all (\elem -> match elem prefix msk) (toList s) && prop_Prefix left && prop_Prefix right
+prop_Prefix _ = True
+
+-- Check that the left elements don't have the mask bit set, and the right
+-- ones do.
+prop_LeftRight :: IntSet -> Bool
+prop_LeftRight (Bin _ msk left right) = and [x .&. msk == 0 | x <- toList left] && and [x .&. msk == msk | x <- toList right]
+prop_LeftRight _ = True
+
+{--------------------------------------------------------------------
+  IntSet operations are like Set operations
+--------------------------------------------------------------------}
+toSet :: IntSet -> Set.Set Int
+toSet = Set.fromList . toList
+
+-- Check that IntSet.isProperSubsetOf is the same as Set.isProperSubsetOf.
+prop_isProperSubsetOf :: IntSet -> IntSet -> Bool
+prop_isProperSubsetOf a b = isProperSubsetOf a b == Set.isProperSubsetOf (toSet a) (toSet b)
+
+-- In the above test, isProperSubsetOf almost always returns False (since a
+-- random set is almost never a subset of another random set).  So this second
+-- test checks the True case.
+prop_isProperSubsetOf2 :: IntSet -> IntSet -> Bool
+prop_isProperSubsetOf2 a b = isProperSubsetOf a c == (a /= c) where
+  c = union a b
}

[Add tiny regression test
David Benbennick <dbenbenn@gmail.com>**20071113045358] {
hunk ./tests/all.T 5
-
+test('dataintset001', normal, compile_and_run, ['-package containers'])
addfile ./tests/dataintset001.hs
hunk ./tests/dataintset001.hs 1
+
+{-
+Through 6.8.1 this printed False, should be True.
+-}
+
+module Main (main) where
+
+import Data.IntSet
+
+main :: IO ()
+main = print $ isProperSubsetOf (fromList [2,3]) $ fromList [2,3,4]
addfile ./tests/dataintset001.stdout
hunk ./tests/dataintset001.stdout 1
+True
}

Context:

[Specify build-type: Simple
Duncan Coutts <duncan@haskell.org>**20071018125404] 
[Add a boring file
Ian Lynagh <igloo@earth.li>**20070913204647] 
[TAG 2007-09-13
Ian Lynagh <igloo@earth.li>**20070913215901] 
Patch bundle hash:
14737998e2fca643fc53bcac37a8d9c03b5e7af2