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Merge branch 'develop' into no-group
commitaacb8a665c40a6fab53a3636e05372ad294d37a3 authorJohn Ericson <John.Ericson@Obsidian.Systems> dateWed 13 Oct 2021, 17:16 (5 years ago) parenta9a9af40019cce
8 files changed+417−274
.github/workflows/haskell.yml+2 ChangeLog.md+8 patch.cabal+13 src/Data/Patch/Class.hs+4−2 src/Data/Patch/DMapWithMove.hs+2−2 src/Data/Patch/MapWithMove.hs+205−182 src/Data/Patch/MapWithPatchingMove.hs+140−88 test/tests.hs+43
.github/workflows/haskell.yml+2
@@ -43,3 +43,5 @@ jobs:
4343 run: cabal build --enable-tests --enable-benchmarks all
4444 - name: Run tests
4545 run: cabal test all
46+ - name: Build Docs
47+ run: cabal haddock
ChangeLog.md+8
@@ -18,6 +18,14 @@
1818* `Additive` now lives in `Data.Semigroup.Additive`, but is still reexported
1919 from `Data.Patch` for compatability.
2020
21+## Unreleased
22+
23+* Rewrite `PatchMapWithMove` in terms of `PatchMapWithPatchingMove`.
24+ Care is taken to make this not a breaking change.
25+ In particular, `PatchMapWithMove` is a newtype of `PatchMapWithPatchingMove`, as is the `NodeInfo` and `From` of `PatchMapWithPatchingMove`'s versions of those.
26+ There are complete constructor and field patterns too, and everything is
27+ exported under the newtype as real constructors and fields would be.
28+
2129## 0.0.4.0
2230
2331* Enable PolyKinds
patch.cabal+13
@@ -57,6 +57,19 @@ library
5757 ghc-options: -Wall -fwarn-redundant-constraints -fwarn-tabs
5858 default-extensions: PolyKinds
5959
60+test-suite tests
61+ default-language: Haskell2010
62+ type: exitcode-stdio-1.0
63+ main-is: tests.hs
64+ hs-source-dirs: test
65+ build-depends: base
66+ , patch
67+ , containers
68+ , hedgehog
69+ , HUnit
70+ if impl(ghcjs)
71+ buildable: False
72+
6073test-suite hlint
6174 default-language: Haskell2010
6275 type: exitcode-stdio-1.0
src/Data/Patch/Class.hs+4−2
@@ -1,9 +1,11 @@
11{-# LANGUAGE CPP #-}
2+{-# LANGUAGE ScopedTypeVariables #-}
23{-# LANGUAGE TypeFamilies #-}
34-- | The interface for types which represent changes made to other types
45module Data.Patch.Class where
56
67import Data.Functor.Identity
8+import Data.Kind (Type)
79import Data.Maybe
810#if !MIN_VERSION_base(4,11,0)
911import Data.Semigroup (Semigroup(..))
@@ -15,7 +17,7 @@ import Data.Proxy
1517-- If an instance of 'Patch' is also an instance of 'Semigroup', it should obey
1618-- the law that @applyAlways (f <> g) == applyAlways f . applyAlways g@.
1719class Patch p where
18− type PatchTarget p :: *
20+ type PatchTarget p :: Type
1921 -- | Apply the patch @p a@ to the value @a@. If no change is needed, return
2022 -- 'Nothing'.
2123 apply :: p -> PatchTarget p -> Maybe (PatchTarget p)
@@ -30,7 +32,7 @@ instance Patch (Identity a) where
3032 apply (Identity a) _ = Just a
3133
3234-- | 'Proxy' can be used as a 'Patch' that does nothing.
33−instance Patch (Proxy (a :: *)) where
35+instance forall (a :: Type). Patch (Proxy a) where
3436 type PatchTarget (Proxy a) = a
3537 apply ~Proxy _ = Nothing
3638
src/Data/Patch/DMapWithMove.hs+2−2
@@ -220,8 +220,8 @@ moveDMapKey src dst = case src `geq` dst of
220220-- @
221221-- let aMay = DMap.lookup a dmap
222222-- bMay = DMap.lookup b dmap
223−-- in maybe id (DMap.insert a) (bMay `mplus` aMay)
224−-- . maybe id (DMap.insert b) (aMay `mplus` bMay)
223+-- in maybe id (DMap.insert a) (bMay <> aMay)
224+-- . maybe id (DMap.insert b) (aMay <> bMay)
225225-- . DMap.delete a . DMap.delete b $ dmap
226226-- @
227227swapDMapKey :: GCompare k => k a -> k a -> PatchDMapWithMove k v
src/Data/Patch/MapWithMove.hs+205−182
@@ -2,98 +2,150 @@
22{-# LANGUAGE DeriveTraversable #-}
33{-# LANGUAGE FlexibleContexts #-}
44{-# LANGUAGE FlexibleInstances #-}
5+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
56{-# LANGUAGE LambdaCase #-}
67{-# LANGUAGE MultiParamTypeClasses #-}
78{-# LANGUAGE PatternGuards #-}
9+{-# LANGUAGE PatternSynonyms #-}
810{-# LANGUAGE ScopedTypeVariables #-}
11+{-# LANGUAGE StandaloneDeriving #-}
912{-# LANGUAGE TemplateHaskell #-}
1013{-# LANGUAGE TypeApplications #-}
1114{-# LANGUAGE TypeFamilies #-}
15+{-# LANGUAGE ViewPatterns #-}
1216
1317-- | 'Patch'es on 'Map' that can insert, delete, and move values from one key to
1418-- another
15−module Data.Patch.MapWithMove where
19+module Data.Patch.MapWithMove
20+ ( PatchMapWithMove
21+ ( PatchMapWithMove
22+ , unPatchMapWithMove
23+ , ..
24+ )
25+ , patchMapWithMove
26+ , patchMapWithMoveInsertAll
27+ , insertMapKey
28+ , moveMapKey
29+ , swapMapKey
30+ , deleteMapKey
31+ , unsafePatchMapWithMove
32+ , patchMapWithMoveNewElements
33+ , patchMapWithMoveNewElementsMap
34+ , patchThatSortsMapWith
35+ , patchThatChangesAndSortsMapWith
36+ , patchThatChangesMap
1637
38+ -- * Node Info
39+ , NodeInfo
40+ ( NodeInfo
41+ , _nodeInfo_to
42+ , _nodeInfo_from
43+ , ..
44+ )
45+ , bitraverseNodeInfo
46+ , nodeInfoMapFrom
47+ , nodeInfoMapMFrom
48+ , nodeInfoSetTo
49+
50+ -- * From
51+ , From
52+ ( From_Insert
53+ , From_Delete
54+ , From_Move
55+ , ..
56+ )
57+ , bitraverseFrom
58+
59+ -- * To
60+ , To
61+ ) where
62+
63+import Data.Coerce
64+import Data.Kind (Type)
1765import Data.Patch.Class
66+import Data.Patch.MapWithPatchingMove (PatchMapWithPatchingMove(..), To)
67+import qualified Data.Patch.MapWithPatchingMove as PM -- already a transparent synonym
1868
19−import Control.Arrow
20−import Control.Lens hiding (from, to)
21−import Control.Monad.Trans.State
22−import Data.Foldable
23−import Data.Function
69+import Control.Lens
2470import Data.List
2571import Data.Map (Map)
2672import qualified Data.Map as Map
27−import Data.Maybe
73+import Data.Proxy
2874#if !MIN_VERSION_base(4,11,0)
2975import Data.Semigroup (Semigroup (..))
3076#endif
31−import qualified Data.Set as Set
32−import Data.These (These(..))
33−import Data.Tuple
77+import Data.Traversable (foldMapDefault)
3478
3579-- | Patch a Map with additions, deletions, and moves. Invariant: If key @k1@
3680-- is coming from @From_Move k2@, then key @k2@ should be going to @Just k1@,
3781-- and vice versa. There should never be any unpaired From/To keys.
38−newtype PatchMapWithMove k v = PatchMapWithMove
39− { -- | Extract the internal representation of the 'PatchMapWithMove'
40− unPatchMapWithMove :: Map k (NodeInfo k v)
82+newtype PatchMapWithMove k (v :: Type) = PatchMapWithMove'
83+ { -- | Extract the underlying 'PatchMapWithPatchingMove k (Proxy v)'
84+ unPatchMapWithMove' :: PatchMapWithPatchingMove k (Proxy v)
4185 }
4286 deriving ( Show, Read, Eq, Ord
43− , Functor, Foldable, Traversable
87+-- Haddock cannot handle documentation here before GHC 8.6
88+ ,
89+#if __GLASGOW_HASKELL__ >= 806
90+ -- | Compose patches having the same effect as applying the
91+ -- patches in turn: @'applyAlways' (p <> q) == 'applyAlways' p .
92+ -- 'applyAlways' q@
93+#endif
94+ Semigroup
95+ , Monoid
4496 )
4597
46−-- | Holds the information about each key: where its new value should come from,
47−-- and where its old value should go to
48−data NodeInfo k v = NodeInfo
49− { _nodeInfo_from :: !(From k v)
50− -- ^ Where do we get the new value for this key?
51− , _nodeInfo_to :: !(To k)
52− -- ^ If the old value is being kept (i.e. moved rather than deleted or
53− -- replaced), where is it going?
54− }
55− deriving (Show, Read, Eq, Ord, Functor, Foldable, Traversable)
98+pattern Coerce :: Coercible a b => a -> b
99+pattern Coerce x <- (coerce -> x)
100+ where Coerce x = coerce x
56101
57−-- | Describe how a key's new value should be produced
58−data From k v
59− = From_Insert v -- ^ Insert the given value here
60− | From_Delete -- ^ Delete the existing value, if any, from here
61− | From_Move !k -- ^ Move the value here from the given key
62− deriving (Show, Read, Eq, Ord, Functor, Foldable, Traversable)
102+{-# COMPLETE PatchMapWithMove #-}
103+pattern PatchMapWithMove :: Map k (NodeInfo k v) -> PatchMapWithMove k v
104+-- | Extract the representation of the 'PatchMapWithMove' as a map of
105+-- 'NodeInfo'.
106+unPatchMapWithMove :: PatchMapWithMove k v -> Map k (NodeInfo k v)
107+pattern PatchMapWithMove { unPatchMapWithMove } = PatchMapWithMove' (PatchMapWithPatchingMove (Coerce unPatchMapWithMove))
63108
64−-- | Describe where a key's old value will go. If this is 'Just', that means
65−-- the key's old value will be moved to the given other key; if it is 'Nothing',
66−-- that means it will be deleted.
67−type To = Maybe
109+_PatchMapWithMove
110+ :: Iso
111+ (PatchMapWithMove k0 v0)
112+ (PatchMapWithMove k1 v1)
113+ (Map k0 (NodeInfo k0 v0))
114+ (Map k1 (NodeInfo k1 v1))
115+_PatchMapWithMove = iso unPatchMapWithMove PatchMapWithMove
68116
69−makeWrapped ''PatchMapWithMove
117+instance Functor (PatchMapWithMove k) where
118+ fmap f = runIdentity . traverse (Identity . f)
119+
120+instance Foldable (PatchMapWithMove k) where
121+ foldMap = foldMapDefault
122+
123+instance Traversable (PatchMapWithMove k) where
124+ traverse =
125+ _PatchMapWithMove .
126+ traverse .
127+ traverse
70128
71129instance FunctorWithIndex k (PatchMapWithMove k)
72130instance FoldableWithIndex k (PatchMapWithMove k)
73131instance TraversableWithIndex k (PatchMapWithMove k) where
74132 itraverse = itraversed . Indexed
75− itraversed = _Wrapped .> itraversed <. traversed
133+ itraversed =
134+ _PatchMapWithMove .>
135+ itraversed <.
136+ traverse
76137
77138-- | Create a 'PatchMapWithMove', validating it
78139patchMapWithMove :: Ord k => Map k (NodeInfo k v) -> Maybe (PatchMapWithMove k v)
79−patchMapWithMove m = if valid then Just $ PatchMapWithMove m else Nothing
80− where valid = forwardLinks == backwardLinks
81− forwardLinks = Map.mapMaybe _nodeInfo_to m
82− backwardLinks = Map.fromList $ catMaybes $ flip fmap (Map.toList m) $ \(to, v) ->
83− case _nodeInfo_from v of
84− From_Move from -> Just (from, to)
85− _ -> Nothing
140+patchMapWithMove = fmap PatchMapWithMove' . PM.patchMapWithPatchingMove . coerce
86141
87142-- | Create a 'PatchMapWithMove' that inserts everything in the given 'Map'
88143patchMapWithMoveInsertAll :: Map k v -> PatchMapWithMove k v
89−patchMapWithMoveInsertAll m = PatchMapWithMove $ flip fmap m $ \v -> NodeInfo
90− { _nodeInfo_from = From_Insert v
91− , _nodeInfo_to = Nothing
92− }
144+patchMapWithMoveInsertAll = PatchMapWithMove' . PM.patchMapWithPatchingMoveInsertAll
93145
94146-- | Make a @'PatchMapWithMove' k v@ which has the effect of inserting or updating a value @v@ to the given key @k@, like 'Map.insert'.
95147insertMapKey :: k -> v -> PatchMapWithMove k v
96−insertMapKey k v = PatchMapWithMove . Map.singleton k $ NodeInfo (From_Insert v) Nothing
148+insertMapKey k v = PatchMapWithMove' $ PM.insertMapKey k v
97149
98150-- |Make a @'PatchMapWithMove' k v@ which has the effect of moving the value from the first key @k@ to the second key @k@, equivalent to:
99151--
@@ -101,84 +153,53 @@ insertMapKey k v = PatchMapWithMove . Map.singleton k $ NodeInfo (From_Insert v)
101153-- 'Map.delete' src (maybe map ('Map.insert' dst) (Map.lookup src map))
102154-- @
103155moveMapKey :: Ord k => k -> k -> PatchMapWithMove k v
104−moveMapKey src dst
105− | src == dst = mempty
106− | otherwise =
107− PatchMapWithMove $ Map.fromList
108− [ (dst, NodeInfo (From_Move src) Nothing)
109− , (src, NodeInfo From_Delete (Just dst))
110− ]
156+moveMapKey src dst = PatchMapWithMove' $ PM.moveMapKey src dst
111157
112158-- |Make a @'PatchMapWithMove' k v@ which has the effect of swapping two keys in the mapping, equivalent to:
113159--
114160-- @
115161-- let aMay = Map.lookup a map
116162-- bMay = Map.lookup b map
117−-- in maybe id (Map.insert a) (bMay `mplus` aMay)
118−-- . maybe id (Map.insert b) (aMay `mplus` bMay)
163+-- in maybe id (Map.insert a) (bMay <> aMay)
164+-- . maybe id (Map.insert b) (aMay <> bMay)
119165-- . Map.delete a . Map.delete b $ map
120166-- @
121167swapMapKey :: Ord k => k -> k -> PatchMapWithMove k v
122−swapMapKey src dst
123− | src == dst = mempty
124− | otherwise =
125− PatchMapWithMove $ Map.fromList
126− [ (dst, NodeInfo (From_Move src) (Just src))
127− , (src, NodeInfo (From_Move dst) (Just dst))
128− ]
168+swapMapKey src dst = PatchMapWithMove' $ PM.swapMapKey src dst
129169
130170-- |Make a @'PatchMapWithMove' k v@ which has the effect of deleting a key in the mapping, equivalent to 'Map.delete'.
131171deleteMapKey :: k -> PatchMapWithMove k v
132−deleteMapKey k = PatchMapWithMove . Map.singleton k $ NodeInfo From_Delete Nothing
172+deleteMapKey = PatchMapWithMove' . PM.deleteMapKey
133173
134174-- | Wrap a @'Map' k (NodeInfo k v)@ representing patch changes into a @'PatchMapWithMove' k v@, without checking any invariants.
135175--
136176-- __Warning:__ when using this function, you must ensure that the invariants of 'PatchMapWithMove' are preserved; they will not be checked.
137177unsafePatchMapWithMove :: Map k (NodeInfo k v) -> PatchMapWithMove k v
138−unsafePatchMapWithMove = PatchMapWithMove
178+unsafePatchMapWithMove = coerce PM.unsafePatchMapWithPatchingMove
139179
140180-- | Apply the insertions, deletions, and moves to a given 'Map'
141181instance Ord k => Patch (PatchMapWithMove k v) where
142182 type PatchTarget (PatchMapWithMove k v) = Map k v
143− apply (PatchMapWithMove p) old = Just $! insertions `Map.union` (old `Map.difference` deletions) --TODO: return Nothing sometimes --Note: the strict application here is critical to ensuring that incremental merges don't hold onto all their prerequisite events forever; can we make this more robust?
144− where insertions = flip Map.mapMaybeWithKey p $ \_ ni -> case _nodeInfo_from ni of
145− From_Insert v -> Just v
146− From_Move k -> Map.lookup k old
147− From_Delete -> Nothing
148− deletions = flip Map.mapMaybeWithKey p $ \_ ni -> case _nodeInfo_from ni of
149− From_Delete -> Just ()
150− _ -> Nothing
183+ apply (PatchMapWithMove' p) = apply p
151184
152185-- | Returns all the new elements that will be added to the 'Map'.
153186patchMapWithMoveNewElements :: PatchMapWithMove k v -> [v]
154−patchMapWithMoveNewElements = Map.elems . patchMapWithMoveNewElementsMap
187+patchMapWithMoveNewElements = PM.patchMapWithPatchingMoveNewElements . unPatchMapWithMove'
155188
156189-- | Return a @'Map' k v@ with all the inserts/updates from the given @'PatchMapWithMove' k v@.
157190patchMapWithMoveNewElementsMap :: PatchMapWithMove k v -> Map k v
158−patchMapWithMoveNewElementsMap (PatchMapWithMove p) = Map.mapMaybe f p
159− where f ni = case _nodeInfo_from ni of
160− From_Insert v -> Just v
161− From_Move _ -> Nothing
162− From_Delete -> Nothing
191+patchMapWithMoveNewElementsMap = PM.patchMapWithPatchingMoveNewElementsMap . unPatchMapWithMove'
163192
164193-- | Create a 'PatchMapWithMove' that, if applied to the given 'Map', will sort
165194-- its values using the given ordering function. The set keys of the 'Map' is
166195-- not changed.
167196patchThatSortsMapWith :: Ord k => (v -> v -> Ordering) -> Map k v -> PatchMapWithMove k v
168−patchThatSortsMapWith cmp m = PatchMapWithMove $ Map.fromList $ catMaybes $ zipWith g unsorted sorted
169− where unsorted = Map.toList m
170− sorted = sortBy (cmp `on` snd) unsorted
171− f (to, _) (from, _) = if to == from then Nothing else
172− Just (from, to)
173− reverseMapping = Map.fromList $ catMaybes $ zipWith f unsorted sorted
174− g (to, _) (from, _) = if to == from then Nothing else
175− let Just movingTo = Map.lookup to reverseMapping
176− in Just (to, NodeInfo (From_Move from) $ Just movingTo)
197+patchThatSortsMapWith cmp = PatchMapWithMove' . PM.patchThatSortsMapWith cmp
177198
178199-- | Create a 'PatchMapWithMove' that, if applied to the first 'Map' provided,
179200-- will produce a 'Map' with the same values as the second 'Map' but with the
180201-- values sorted with the given ordering function.
181−patchThatChangesAndSortsMapWith :: forall k v. (Ord k, Ord v) => (v -> v -> Ordering) -> Map k v -> Map k v -> PatchMapWithMove k v
202+patchThatChangesAndSortsMapWith :: (Ord k, Ord v) => (v -> v -> Ordering) -> Map k v -> Map k v -> PatchMapWithMove k v
182203patchThatChangesAndSortsMapWith cmp oldByIndex newByIndexUnsorted = patchThatChangesMap oldByIndex newByIndex
183204 where newList = Map.toList newByIndexUnsorted
184205 newByIndex = Map.fromList $ zip (fst <$> newList) $ sortBy cmp $ snd <$> newList
@@ -186,104 +207,106 @@ patchThatChangesAndSortsMapWith cmp oldByIndex newByIndexUnsorted = patchThatCha
186207-- | Create a 'PatchMapWithMove' that, if applied to the first 'Map' provided,
187208-- will produce the second 'Map'.
188209patchThatChangesMap :: (Ord k, Ord v) => Map k v -> Map k v -> PatchMapWithMove k v
189−patchThatChangesMap oldByIndex newByIndex = patch
190− where oldByValue = Map.fromListWith Set.union $ swap . first Set.singleton <$> Map.toList oldByIndex
191− (insertsAndMoves, unusedValuesByValue) = flip runState oldByValue $ do
192− let f k v = do
193− remainingValues <- get
194− let putRemainingKeys remainingKeys = put $ if Set.null remainingKeys
195− then Map.delete v remainingValues
196− else Map.insert v remainingKeys remainingValues
197− case Map.lookup v remainingValues of
198− Nothing -> return $ NodeInfo (From_Insert v) $ Just undefined -- There's no existing value we can take
199− Just fromKs ->
200− if k `Set.member` fromKs
201− then do
202− putRemainingKeys $ Set.delete k fromKs
203− return $ NodeInfo (From_Move k) $ Just undefined -- There's an existing value, and it's here, so no patch necessary
204− else do
205− (fromK, remainingKeys) <- return $
206− fromMaybe (error "PatchMapWithMove.patchThatChangesMap: impossible: fromKs was empty") $
207− Set.minView fromKs -- There's an existing value, but it's not here; move it here
208− putRemainingKeys remainingKeys
209− return $ NodeInfo (From_Move fromK) $ Just undefined
210− Map.traverseWithKey f newByIndex
211− unusedOldKeys = fold unusedValuesByValue
212− pointlessMove k = \case
213− From_Move k' | k == k' -> True
214− _ -> False
215− keyWasMoved k = if k `Map.member` oldByIndex && not (k `Set.member` unusedOldKeys)
216− then Just undefined
217− else Nothing
218− patch = unsafePatchMapWithMove $ Map.filterWithKey (\k -> not . pointlessMove k . _nodeInfo_from) $ Map.mergeWithKey (\k a _ -> Just $ nodeInfoSetTo (keyWasMoved k) a) (Map.mapWithKey $ \k -> nodeInfoSetTo $ keyWasMoved k) (Map.mapWithKey $ \k _ -> NodeInfo From_Delete $ keyWasMoved k) insertsAndMoves oldByIndex
210+patchThatChangesMap oldByIndex newByIndex = PatchMapWithMove' $
211+ PM.patchThatChangesMap oldByIndex newByIndex
212+
213+--
214+-- NodeInfo
215+--
216+
217+-- | Holds the information about each key: where its new value should come from,
218+-- and where its old value should go to
219+newtype NodeInfo k (v :: Type) = NodeInfo' { unNodeInfo' :: PM.NodeInfo k (Proxy v) }
220+
221+deriving instance (Show k, Show p) => Show (NodeInfo k p)
222+deriving instance (Read k, Read p) => Read (NodeInfo k p)
223+deriving instance (Eq k, Eq p) => Eq (NodeInfo k p)
224+deriving instance (Ord k, Ord p) => Ord (NodeInfo k p)
225+
226+{-# COMPLETE NodeInfo #-}
227+pattern NodeInfo :: To k -> From k v -> NodeInfo k v
228+_nodeInfo_to :: NodeInfo k v -> To k
229+_nodeInfo_from :: NodeInfo k v -> From k v
230+pattern NodeInfo { _nodeInfo_to, _nodeInfo_from } = NodeInfo'
231+ PM.NodeInfo
232+ { PM._nodeInfo_to = _nodeInfo_to
233+ , PM._nodeInfo_from = Coerce _nodeInfo_from
234+ }
235+
236+_NodeInfo
237+ :: Iso
238+ (NodeInfo k0 v0)
239+ (NodeInfo k1 v1)
240+ (PM.NodeInfo k0 (Proxy v0))
241+ (PM.NodeInfo k1 (Proxy v1))
242+_NodeInfo = iso unNodeInfo' NodeInfo'
243+
244+instance Functor (NodeInfo k) where
245+ fmap f = runIdentity . traverse (Identity . f)
246+
247+instance Foldable (NodeInfo k) where
248+ foldMap = foldMapDefault
249+
250+instance Traversable (NodeInfo k) where
251+ traverse = bitraverseNodeInfo pure
252+
253+bitraverseNodeInfo
254+ :: Applicative f
255+ => (k0 -> f k1)
256+ -> (v0 -> f v1)
257+ -> NodeInfo k0 v0 -> f (NodeInfo k1 v1)
258+bitraverseNodeInfo fk fv = fmap NodeInfo'
259+ . PM.bitraverseNodeInfo fk (\ ~Proxy -> pure Proxy) fv
260+ . coerce
219261
220262-- | Change the 'From' value of a 'NodeInfo'
221263nodeInfoMapFrom :: (From k v -> From k v) -> NodeInfo k v -> NodeInfo k v
222−nodeInfoMapFrom f ni = ni { _nodeInfo_from = f $ _nodeInfo_from ni }
264+nodeInfoMapFrom f = coerce $ PM.nodeInfoMapFrom (unFrom' . f . From')
223265
224266-- | Change the 'From' value of a 'NodeInfo', using a 'Functor' (or
225267-- 'Applicative', 'Monad', etc.) action to get the new value
226−nodeInfoMapMFrom :: Functor f => (From k v -> f (From k v)) -> NodeInfo k v -> f (NodeInfo k v)
227−nodeInfoMapMFrom f ni = fmap (\result -> ni { _nodeInfo_from = result }) $ f $ _nodeInfo_from ni
268+nodeInfoMapMFrom
269+ :: Functor f
270+ => (From k v -> f (From k v))
271+ -> NodeInfo k v -> f (NodeInfo k v)
272+nodeInfoMapMFrom f = fmap NodeInfo'
273+ . PM.nodeInfoMapMFrom (fmap unFrom' . f . From')
274+ . coerce
228275
229276-- | Set the 'To' field of a 'NodeInfo'
230277nodeInfoSetTo :: To k -> NodeInfo k v -> NodeInfo k v
231−nodeInfoSetTo to ni = ni { _nodeInfo_to = to }
232−
233−-- |Helper data structure used for composing patches using the monoid instance.
234−data Fixup k v
235− = Fixup_Delete
236− | Fixup_Update (These (From k v) (To k))
237−
238−-- |Compose patches having the same effect as applying the patches in turn: @'applyAlways' (p <> q) == 'applyAlways' p . 'applyAlways' q@
239−instance Ord k => Semigroup (PatchMapWithMove k v) where
240− PatchMapWithMove ma <> PatchMapWithMove mb = PatchMapWithMove m
241− where
242− connections = Map.toList $ Map.intersectionWithKey (\_ a b -> (_nodeInfo_to a, _nodeInfo_from b)) ma mb
243− h :: (k, (Maybe k, From k v)) -> [(k, Fixup k v)]
244− h (_, (mToAfter, editBefore)) = case (mToAfter, editBefore) of
245− (Just toAfter, From_Move fromBefore)
246− | fromBefore == toAfter
247− -> [(toAfter, Fixup_Delete)]
248− | otherwise
249− -> [ (toAfter, Fixup_Update (This editBefore))
250− , (fromBefore, Fixup_Update (That mToAfter))
251− ]
252− (Nothing, From_Move fromBefore) -> [(fromBefore, Fixup_Update (That mToAfter))] -- The item is destroyed in the second patch, so indicate that it is destroyed in the source map
253− (Just toAfter, _) -> [(toAfter, Fixup_Update (This editBefore))]
254− (Nothing, _) -> []
255− mergeFixups _ Fixup_Delete Fixup_Delete = Fixup_Delete
256− mergeFixups _ (Fixup_Update a) (Fixup_Update b)
257− | This x <- a, That y <- b
258− = Fixup_Update $ These x y
259− | That y <- a, This x <- b
260− = Fixup_Update $ These x y
261− mergeFixups _ _ _ = error "PatchMapWithMove: incompatible fixups"
262− fixups = Map.fromListWithKey mergeFixups $ concatMap h connections
263− combineNodeInfos _ nia nib = NodeInfo
264− { _nodeInfo_from = _nodeInfo_from nia
265− , _nodeInfo_to = _nodeInfo_to nib
266− }
267− applyFixup _ ni = \case
268− Fixup_Delete -> Nothing
269− Fixup_Update u -> Just $ NodeInfo
270− { _nodeInfo_from = fromMaybe (_nodeInfo_from ni) $ getHere u
271− , _nodeInfo_to = fromMaybe (_nodeInfo_to ni) $ getThere u
272− }
273− m = Map.differenceWithKey applyFixup (Map.unionWithKey combineNodeInfos ma mb) fixups
274− getHere :: These a b -> Maybe a
275− getHere = \case
276− This a -> Just a
277− These a _ -> Just a
278− That _ -> Nothing
279− getThere :: These a b -> Maybe b
280− getThere = \case
281− This _ -> Nothing
282− These _ b -> Just b
283− That b -> Just b
284−
285−--TODO: Figure out how to implement this in terms of PatchDMapWithMove rather than duplicating it here
286−-- |Compose patches having the same effect as applying the patches in turn: @'applyAlways' (p <> q) == 'applyAlways' p . 'applyAlways' q@
287−instance Ord k => Monoid (PatchMapWithMove k v) where
288− mempty = PatchMapWithMove mempty
289− mappend = (<>)
278+nodeInfoSetTo = coerce . PM.nodeInfoSetTo
279+
280+--
281+-- From
282+--
283+
284+-- | Describe how a key's new value should be produced
285+newtype From k (v :: Type) = From' { unFrom' :: PM.From k (Proxy v) }
286+
287+{-# COMPLETE From_Insert, From_Delete, From_Move #-}
288+
289+-- | Insert the given value here
290+pattern From_Insert :: v -> From k v
291+pattern From_Insert v = From' (PM.From_Insert v)
292+
293+-- | Delete the existing value, if any, from here
294+pattern From_Delete :: From k v
295+pattern From_Delete = From' PM.From_Delete
296+
297+-- | Move the value here from the given key
298+pattern From_Move :: k -> From k v
299+pattern From_Move k = From' (PM.From_Move k Proxy)
300+
301+bitraverseFrom
302+ :: Applicative f
303+ => (k0 -> f k1)
304+ -> (v0 -> f v1)
305+ -> From k0 v0 -> f (From k1 v1)
306+bitraverseFrom fk fv = fmap From'
307+ . PM.bitraverseFrom fk (\ ~Proxy -> pure Proxy) fv
308+ . coerce
309+
310+makeWrapped ''PatchMapWithMove
311+makeWrapped ''NodeInfo
312+makeWrapped ''From
src/Data/Patch/MapWithPatchingMove.hs+140−88
@@ -13,14 +13,45 @@
1313
1414-- | 'Patch'es on 'Map' that can insert, delete, and move values from one key to
1515-- another
16−module Data.Patch.MapWithPatchingMove where
16+module Data.Patch.MapWithPatchingMove
17+ ( PatchMapWithPatchingMove (..)
18+ , patchMapWithPatchingMove
19+ , patchMapWithPatchingMoveInsertAll
20+ , insertMapKey
21+ , moveMapKey
22+ , swapMapKey
23+ , deleteMapKey
24+ , unsafePatchMapWithPatchingMove
25+ , patchMapWithPatchingMoveNewElements
26+ , patchMapWithPatchingMoveNewElementsMap
27+ , patchThatSortsMapWith
28+ , patchThatChangesAndSortsMapWith
29+ , patchThatChangesMap
30+
31+ -- * Node Info
32+ , NodeInfo (..)
33+ , bitraverseNodeInfo
34+ , nodeInfoMapFrom
35+ , nodeInfoMapMFrom
36+ , nodeInfoSetTo
37+
38+ -- * From
39+ , From(..)
40+ , bitraverseFrom
41+
42+ -- * To
43+ , To
44+
45+ -- TODO internals module
46+ , Fixup (..)
47+ ) where
1748
1849import Data.Patch.Class
1950
20−import Control.Arrow
51+import Control.Lens hiding (from, to)
2152import Control.Lens.TH (makeWrapped)
22−import Control.Monad.Trans.State
23−import Data.Foldable
53+import Data.Align (align)
54+import Data.Foldable (toList)
2455import Data.Function
2556import Data.List
2657import Data.Map (Map)
@@ -30,9 +61,9 @@ import Data.Maybe
3061import Data.Semigroup (Semigroup (..))
3162#endif
3263import Data.Monoid.DecidablyEmpty
64+import Data.Set (Set)
3365import qualified Data.Set as Set
3466import Data.These (These (..))
35−import Data.Tuple
3667
3768-- | Patch a Map with additions, deletions, and moves. Invariant: If key @k1@
3869-- is coming from @From_Move k2@, then key @k2@ should be going to @Just k1@,
@@ -55,57 +86,6 @@ deriving instance ( Ord k
5586 , Patch p
5687 ) => DecidablyEmpty (PatchMapWithPatchingMove k p)
5788
58−-- | Holds the information about each key: where its new value should come from,
59−-- and where its old value should go to
60−data NodeInfo k p = NodeInfo
61− { _nodeInfo_from :: !(From k p)
62− -- ^ Where do we get the new value for this key?
63− , _nodeInfo_to :: !(To k)
64− -- ^ If the old value is being kept (i.e. moved rather than deleted or
65− -- replaced), where is it going?
66− }
67−deriving instance (Show k, Show p, Show (PatchTarget p)) => Show (NodeInfo k p)
68−deriving instance (Read k, Read p, Read (PatchTarget p)) => Read (NodeInfo k p)
69−deriving instance (Eq k, Eq p, Eq (PatchTarget p)) => Eq (NodeInfo k p)
70−deriving instance (Ord k, Ord p, Ord (PatchTarget p)) => Ord (NodeInfo k p)
71−
72−bitraverseNodeInfo
73− :: Applicative f
74− => (k0 -> f k1)
75− -> (p0 -> f p1)
76− -> (PatchTarget p0 -> f (PatchTarget p1))
77− -> NodeInfo k0 p0 -> f (NodeInfo k1 p1)
78−bitraverseNodeInfo fk fp fpt (NodeInfo from to) = NodeInfo
79− <$> bitraverseFrom fk fp fpt from
80− <*> traverse fk to
81−
82−-- | Describe how a key's new value should be produced
83−data From k p
84− = From_Insert (PatchTarget p) -- ^ Insert the given value here
85− | From_Delete -- ^ Delete the existing value, if any, from here
86− | From_Move !k !p -- ^ Move the value here from the given key, and apply the given patch
87−
88−bitraverseFrom
89− :: Applicative f
90− => (k0 -> f k1)
91− -> (p0 -> f p1)
92− -> (PatchTarget p0 -> f (PatchTarget p1))
93− -> From k0 p0 -> f (From k1 p1)
94−bitraverseFrom fk fp fpt = \case
95− From_Insert pt -> From_Insert <$> fpt pt
96− From_Delete -> pure From_Delete
97− From_Move k p -> From_Move <$> fk k <*> fp p
98−
99−deriving instance (Show k, Show p, Show (PatchTarget p)) => Show (From k p)
100−deriving instance (Read k, Read p, Read (PatchTarget p)) => Read (From k p)
101−deriving instance (Eq k, Eq p, Eq (PatchTarget p)) => Eq (From k p)
102−deriving instance (Ord k, Ord p, Ord (PatchTarget p)) => Ord (From k p)
103−
104−-- | Describe where a key's old value will go. If this is 'Just', that means
105−-- the key's old value will be moved to the given other key; if it is 'Nothing',
106−-- that means it will be deleted.
107−type To = Maybe
108−
10989-- | Create a 'PatchMapWithPatchingMove', validating it
11090patchMapWithPatchingMove
11191 :: Ord k => Map k (NodeInfo k p) -> Maybe (PatchMapWithPatchingMove k p)
@@ -156,8 +136,8 @@ moveMapKey src dst
156136-- @
157137-- let aMay = Map.lookup a map
158138-- bMay = Map.lookup b map
159−-- in maybe id (Map.insert a) (bMay `mplus` aMay)
160−-- . maybe id (Map.insert b) (aMay `mplus` bMay)
139+-- in maybe id (Map.insert a) (bMay <> aMay)
140+-- . maybe id (Map.insert b) (aMay <> bMay)
161141-- . Map.delete a . Map.delete b $ map
162142-- @
163143swapMapKey
@@ -249,39 +229,70 @@ patchThatChangesAndSortsMapWith cmp oldByIndex newByIndexUnsorted = patchThatCha
249229
250230-- | Create a 'PatchMapWithPatchingMove' that, if applied to the first 'Map' provided,
251231-- will produce the second 'Map'.
232+-- Note: this will never produce a patch on a value.
252233patchThatChangesMap
253− :: (Ord k, Ord (PatchTarget p), Monoid p)
234+ :: forall k p
235+ . (Ord k, Ord (PatchTarget p), Monoid p)
254236 => Map k (PatchTarget p) -> Map k (PatchTarget p) -> PatchMapWithPatchingMove k p
255237patchThatChangesMap oldByIndex newByIndex = patch
256− where oldByValue = Map.fromListWith Set.union $ swap . first Set.singleton <$> Map.toList oldByIndex
257− (insertsAndMoves, unusedValuesByValue) = flip runState oldByValue $ do
258− let f k v = do
259− remainingValues <- get
260− let putRemainingKeys remainingKeys = put $ if Set.null remainingKeys
261− then Map.delete v remainingValues
262− else Map.insert v remainingKeys remainingValues
263− case Map.lookup v remainingValues of
264− Nothing -> return $ NodeInfo (From_Insert v) $ Just undefined -- There's no existing value we can take
265− Just fromKs ->
266− if k `Set.member` fromKs
267− then do
268− putRemainingKeys $ Set.delete k fromKs
269− return $ NodeInfo (From_Move k mempty) $ Just undefined -- There's an existing value, and it's here, so no patch necessary
270− else do
271− (fromK, remainingKeys) <- return $
272− fromMaybe (error "PatchMapWithPatchingMove.patchThatChangesMap: impossible: fromKs was empty") $
273− Set.minView fromKs -- There's an existing value, but it's not here; move it here
274− putRemainingKeys remainingKeys
275− return $ NodeInfo (From_Move fromK mempty) $ Just undefined
276− Map.traverseWithKey f newByIndex
277− unusedOldKeys = fold unusedValuesByValue
278− pointlessMove k = \case
279− From_Move k' _ | k == k' -> True
280− _ -> False
281− keyWasMoved k = if k `Map.member` oldByIndex && not (k `Set.member` unusedOldKeys)
282− then Just undefined
283− else Nothing
284− patch = unsafePatchMapWithPatchingMove $ Map.filterWithKey (\k -> not . pointlessMove k . _nodeInfo_from) $ Map.mergeWithKey (\k a _ -> Just $ nodeInfoSetTo (keyWasMoved k) a) (Map.mapWithKey $ \k -> nodeInfoSetTo $ keyWasMoved k) (Map.mapWithKey $ \k _ -> NodeInfo From_Delete $ keyWasMoved k) insertsAndMoves oldByIndex
238+ where invert :: Map k (PatchTarget p) -> Map (PatchTarget p) (Set k)
239+ invert = Map.fromListWith (<>) . fmap (\(k, v) -> (v, Set.singleton k)) . Map.toList
240+ -- In the places where we use unionDistinct, a non-distinct key indicates a bug in this function
241+ unionDistinct :: forall k' v'. Ord k' => Map k' v' -> Map k' v' -> Map k' v'
242+ unionDistinct = Map.unionWith (error "patchThatChangesMap: non-distinct keys")
243+ unionPairDistinct :: (Map k (From k v), Map k (To k)) -> (Map k (From k v), Map k (To k)) -> (Map k (From k v), Map k (To k))
244+ unionPairDistinct (oldFroms, oldTos) (newFroms, newTos) = (unionDistinct oldFroms newFroms, unionDistinct oldTos newTos)
245+ -- Generate patch info for a single value
246+ -- Keys that are found in both the old and new sets will not be patched
247+ -- Keys that are found in only the old set will be moved to a new position if any are available; otherwise they will be deleted
248+ -- Keys that are found in only the new set will be populated by moving an old key if any are available; otherwise they will be inserted
249+ patchSingleValue :: PatchTarget p -> Set k -> Set k -> (Map k (From k p), Map k (To k))
250+ patchSingleValue v oldKeys newKeys = foldl' unionPairDistinct mempty $ align (toList $ oldKeys `Set.difference` newKeys) (toList $ newKeys `Set.difference` oldKeys) <&> \case
251+ This oldK -> (mempty, Map.singleton oldK Nothing) -- There's nowhere for this value to go, so we know we are deleting it
252+ That newK -> (Map.singleton newK $ From_Insert v, mempty) -- There's nowhere fo this value to come from, so we know we are inserting it
253+ These oldK newK -> (Map.singleton newK $ From_Move oldK mempty, Map.singleton oldK $ Just newK)
254+ -- Run patchSingleValue on a These. Missing old or new sets are considered empty
255+ patchSingleValueThese :: PatchTarget p -> These (Set k) (Set k) -> (Map k (From k p), Map k (To k))
256+ patchSingleValueThese v = \case
257+ This oldKeys -> patchSingleValue v oldKeys mempty
258+ That newKeys -> patchSingleValue v mempty newKeys
259+ These oldKeys newKeys -> patchSingleValue v oldKeys newKeys
260+ -- Generate froms and tos for all values, then merge them together
261+ (froms, tos) = foldl' unionPairDistinct mempty $ Map.mapWithKey patchSingleValueThese $ align (invert oldByIndex) (invert newByIndex)
262+ patch = unsafePatchMapWithPatchingMove $ align froms tos <&> \case
263+ This from -> NodeInfo from Nothing -- Since we don't have a 'to' record for this key, that must mean it isn't being moved anywhere, so it should be deleted.
264+ That to -> NodeInfo From_Delete to -- Since we don't have a 'from' record for this key, it must be getting deleted
265+ These from to -> NodeInfo from to
266+
267+--
268+-- NodeInfo
269+--
270+
271+-- | Holds the information about each key: where its new value should come from,
272+-- and where its old value should go to
273+data NodeInfo k p = NodeInfo
274+ { _nodeInfo_from :: !(From k p)
275+ -- ^ Where do we get the new value for this key?
276+ , _nodeInfo_to :: !(To k)
277+ -- ^ If the old value is being kept (i.e. moved rather than deleted or
278+ -- replaced), where is it going?
279+ }
280+deriving instance (Show k, Show p, Show (PatchTarget p)) => Show (NodeInfo k p)
281+deriving instance (Read k, Read p, Read (PatchTarget p)) => Read (NodeInfo k p)
282+deriving instance (Eq k, Eq p, Eq (PatchTarget p)) => Eq (NodeInfo k p)
283+deriving instance (Ord k, Ord p, Ord (PatchTarget p)) => Ord (NodeInfo k p)
284+
285+-- | Traverse the 'NodeInfo' over the key, patch, and patch target. Because of
286+-- the type families here, this doesn't it any bi- or tri-traversal class.
287+bitraverseNodeInfo
288+ :: Applicative f
289+ => (k0 -> f k1)
290+ -> (p0 -> f p1)
291+ -> (PatchTarget p0 -> f (PatchTarget p1))
292+ -> NodeInfo k0 p0 -> f (NodeInfo k1 p1)
293+bitraverseNodeInfo fk fp fpt (NodeInfo from to) = NodeInfo
294+ <$> bitraverseFrom fk fp fpt from
295+ <*> traverse fk to
285296
286297-- | Change the 'From' value of a 'NodeInfo'
287298nodeInfoMapFrom
@@ -299,6 +310,47 @@ nodeInfoSetTo
299310 :: To k -> NodeInfo k v -> NodeInfo k v
300311nodeInfoSetTo to ni = ni { _nodeInfo_to = to }
301312
313+--
314+-- From
315+--
316+
317+-- | Describe how a key's new value should be produced
318+data From k p
319+ = From_Insert (PatchTarget p) -- ^ Insert the given value here
320+ | From_Delete -- ^ Delete the existing value, if any, from here
321+ | From_Move !k !p -- ^ Move the value here from the given key, and apply the given patch
322+
323+deriving instance (Show k, Show p, Show (PatchTarget p)) => Show (From k p)
324+deriving instance (Read k, Read p, Read (PatchTarget p)) => Read (From k p)
325+deriving instance (Eq k, Eq p, Eq (PatchTarget p)) => Eq (From k p)
326+deriving instance (Ord k, Ord p, Ord (PatchTarget p)) => Ord (From k p)
327+
328+-- | Traverse the 'From' over the key, patch, and patch target. Because of
329+-- the type families here, this doesn't it any bi- or tri-traversal class.
330+bitraverseFrom
331+ :: Applicative f
332+ => (k0 -> f k1)
333+ -> (p0 -> f p1)
334+ -> (PatchTarget p0 -> f (PatchTarget p1))
335+ -> From k0 p0 -> f (From k1 p1)
336+bitraverseFrom fk fp fpt = \case
337+ From_Insert pt -> From_Insert <$> fpt pt
338+ From_Delete -> pure From_Delete
339+ From_Move k p -> From_Move <$> fk k <*> fp p
340+
341+--
342+-- To
343+--
344+
345+-- | Describe where a key's old value will go. If this is 'Just', that means
346+-- the key's old value will be moved to the given other key; if it is 'Nothing',
347+-- that means it will be deleted.
348+type To = Maybe
349+
350+--
351+-- Fixup
352+--
353+
302354-- | Helper data structure used for composing patches using the monoid instance.
303355data Fixup k v
304356 = Fixup_Delete
test/tests.hsnew file+43
@@ -0,0 +1,43 @@
1+{-# LANGUAGE TemplateHaskell #-}
2+module Main where
3+
4+import Test.HUnit (runTestTT, (~:), assertEqual, errors, failures, test)
5+import Data.Patch ( Patch(apply) )
6+import Data.Patch.MapWithMove ( patchThatChangesMap )
7+import Data.Map as Map ( Map, fromList, singleton )
8+import Hedgehog (checkParallel, discover, Property, property, forAll, PropertyT, (===))
9+import Hedgehog.Gen as Gen ( int )
10+import Hedgehog.Range as Range ( linear )
11+import Control.Monad (replicateM)
12+import System.Exit (exitFailure, exitSuccess)
13+import Data.Sequence as Seq ( foldMapWithIndex, replicateM )
14+
15+main :: IO ()
16+main = do
17+ counts <- runTestTT $ test [
18+ "Simple Move" ~: (do
19+ let mapBefore = Map.fromList [(0,1)]
20+ mapAfter = Map.fromList [(0,0),(1,1)]
21+ patch = patchThatChangesMap mapBefore mapAfter
22+ afterPatch = apply patch mapBefore
23+ assertEqual "Patch creates the same Map" (Just mapAfter) afterPatch),
24+ "Property Checks" ~: propertyChecks
25+ ]
26+ if errors counts + failures counts == 0 then exitSuccess else exitFailure
27+
28+propertyChecks :: IO Bool
29+propertyChecks = checkParallel $$(discover)
30+
31+prop_patchThatChangesMap :: Property
32+prop_patchThatChangesMap = property $ do
33+ mapBefore <- makeRandomIntMap
34+ mapAfter <- makeRandomIntMap
35+ let patch = patchThatChangesMap mapBefore mapAfter
36+ Just mapAfter === apply patch mapBefore
37+
38+makeRandomIntMap :: Monad m => PropertyT m (Map Int Int)
39+makeRandomIntMap = do
40+ let genNum = Gen.int (Range.linear 0 100)
41+ length <- forAll genNum
42+ listOfNumbers <- forAll $ Seq.replicateM length genNum
43+ pure $ Seq.foldMapWithIndex Map.singleton listOfNumbers