1 files changed, 70 insertions, 0 deletions
diff --git a/tests/Properties/Shift.hs b/tests/Properties/Shift.hs
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+++ b/tests/Properties/Shift.hs
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+{-# LANGUAGE ScopedTypeVariables #-}
+module Properties.Shift where
+
+import Test.QuickCheck
+import Instances
+import Utils
+
+import XMonad.StackSet hiding (filter)
+
+import qualified Data.List as L
+
+-- ---------------------------------------------------------------------
+-- shift
+
+-- shift is fully reversible on current window, when focus and master
+-- are the same. otherwise, master may move.
+prop_shift_reversible (x :: T) = do
+    i <- arbitraryTag x
+    case peek y of
+      Nothing -> return True
+      Just _  -> return $ normal ((view n . shift n . view i . shift i) y) == normal y
+    where
+        y = swapMaster x
+        n = currentTag y
+
+------------------------------------------------------------------------
+-- shiftMaster
+
+-- focus/local/idempotent same as swapMaster:
+prop_shift_master_focus (x :: T) = peek x == (peek $ shiftMaster x)
+prop_shift_master_local (x :: T) = hidden_spaces x == hidden_spaces (shiftMaster x)
+prop_shift_master_idempotent (x :: T) = shiftMaster (shiftMaster x) == shiftMaster x
+-- ordering is constant modulo the focused window:
+prop_shift_master_ordering (x :: T) = case peek x of
+    Nothing -> True
+    Just m  -> L.delete m (index x) == L.delete m (index $ shiftMaster x)
+
+-- ---------------------------------------------------------------------
+-- shiftWin
+
+-- shiftWin on current window is the same as shift
+prop_shift_win_focus (x :: T) = do
+    n <- arbitraryTag x
+    case peek x of
+      Nothing -> return True
+      Just w  -> return $ shiftWin n w x == shift n x
+
+-- shiftWin on a non-existant window is identity
+prop_shift_win_indentity (x :: T) = do
+    n <- arbitraryTag x
+    w <- arbitrary `suchThat` \w' -> not (w' `member` x)
+    return $ shiftWin n w x == x
+
+-- shiftWin leaves the current screen as it is, if neither n is the tag
+-- of the current workspace nor w on the current workspace
+prop_shift_win_fix_current = do
+  x <- arbitrary `suchThat` \(x' :: T) ->
+         -- Invariant, otherWindows are NOT in the current workspace.
+         let otherWindows = allWindows x' L.\\ index x'
+         in  length(tags x') >= 2 && length(otherWindows) >= 1
+  -- Sadly we have to construct `otherWindows` again, for the actual StackSet
+  -- that got chosen.
+  let otherWindows = allWindows x L.\\ index x
+  -- We know such tag must exists, due to the precondition
+  n <- arbitraryTag x `suchThat` (/= currentTag x)
+  -- we know length is >= 1, from above precondition
+  idx <- choose(0, length(otherWindows) - 1)
+  let w = otherWindows !! idx
+  return $ (current $ x) == (current $ shiftWin n w x)
+