Add subsetOf Filter function

src/Internal/Filter/Timeline.elm

@@ -3,6 +3,7 @@ module Internal.Filter.Timeline exposing
     , pass, onlySenders, allSendersExcept, onlyTypes, allTypesExcept, fail
     , match, run
     , and
+    , subsetOf
     )
 
 {-|
@@ -33,6 +34,11 @@ for interacting with the Matrix API.
 
 @docs and
 
+
+## Compare
+
+@docs subsetOf
+
 -}
 
 import Set exposing (Set)
@@ -132,15 +138,15 @@ and (Filter f1) (Filter f2) =
 
                         ( False, False ) ->
                             Set.intersect f1.types f2.types
-                , typesAllowOthers = f2.typesAllowOthers && f2.typesAllowOthers
+                , typesAllowOthers = f1.typesAllowOthers && f2.typesAllowOthers
                 }
     in
     case stdAnd of
         Filter f ->
-            if Set.isEmpty f.senders && (not f.sendersAllowOthers) then
+            if Set.isEmpty f.senders && not f.sendersAllowOthers then
                 fail
 
-            else if Set.isEmpty f.types && (not f.typesAllowOthers) then
+            else if Set.isEmpty f.types && not f.typesAllowOthers then
                 fail
 
             else
@@ -235,3 +241,36 @@ pass =
 run : Filter -> List (Event a) -> List (Event a)
 run f events =
     List.filter (match f) events
+
+
+{-| Determine whether the second argument is a subset filter of the first
+argument.
+-}
+subsetOf : Filter -> Filter -> Bool
+subsetOf (Filter big) (Filter small) =
+    let
+        isSSof : Set String -> Set String -> Bool
+        isSSof b s =
+            Set.intersect b s == s
+
+        isSubsetFor : ( Bool, Set String ) -> ( Bool, Set String ) -> Bool
+        isSubsetFor ( bb, sb ) ( bs, ss ) =
+            case ( bb, bs ) of
+                ( True, True ) ->
+                    isSSof ss sb
+
+                ( True, False ) ->
+                    Set.isEmpty (Set.intersect sb ss)
+
+                ( False, True ) ->
+                    False
+
+                ( False, False ) ->
+                    isSSof sb ss
+    in
+    isSubsetFor
+        ( big.sendersAllowOthers, big.senders )
+        ( small.sendersAllowOthers, small.senders )
+        && isSubsetFor
+            ( big.typesAllowOthers, big.types )
+            ( small.typesAllowOthers, small.types )

src/Internal/Values/Event.elm

@@ -1,7 +1,8 @@
 module Internal.Values.Event exposing
     ( Event
     , UnsignedData(..), age, prevContent, redactedBecause, transactionId
-    , encode, decoder, isEqual
+    , encode, decoder
+    , isEqual
     )
 
 {-|
@@ -24,6 +25,7 @@ of a room.
 
 @docs encode, decoder
 
+
 ## Test functions
 
 @docs isEqual
@@ -133,16 +135,22 @@ isEqual : Event -> Event -> Bool
 isEqual e1 e2 =
     if e1.eventId /= e2.eventId then
         False
+
     else if e1.originServerTs /= e2.originServerTs then
         False
+
     else if e1.roomId /= e2.roomId then
         False
+
     else if e1.sender /= e2.sender then
         False
+
     else if e1.stateKey /= e2.stateKey then
         False
+
     else if e1.eventType /= e2.eventType then
         False
+
     else
         case ( e1.unsigned, e2.unsigned ) of
             ( Nothing, Nothing ) ->
@@ -157,10 +165,13 @@ isEqual e1 e2 =
             ( Just (UnsignedData d1), Just (UnsignedData d2) ) ->
                 if d1.age /= d2.age then
                     False
+
                 else if d1.transactionId /= d2.transactionId then
                     False
+
                 else if Maybe.map (E.encode 0) d1.prevContent /= Maybe.map (E.encode 0) d2.prevContent then
                     False
+
                 else
                     case ( d1.redactedBecause, d2.redactedBecause ) of
                         ( Nothing, Nothing ) ->
@@ -175,6 +186,7 @@ isEqual e1 e2 =
                         ( Just se1, Just se2 ) ->
                             isEqual se1 se2
 
+
 {-| Determine the previous `content` value for this event. This field is only a
 `Just value` if the event is a state event, and the Matrix Vault has permission
 to see the previous content.

tests/Test/Filter/Timeline.elm

@@ -4,6 +4,7 @@ import Expect
 import Fuzz exposing (Fuzzer)
 import Internal.Filter.Timeline as Filter exposing (Filter)
 import Internal.Values.Event as Event
+import Set
 import Test exposing (..)
 import Test.Values.Event as TestEvent
 
@@ -138,6 +139,138 @@ suite =
                         |> Filter.and (Filter.allTypesExcept types)
                         |> Expect.equal Filter.fail
                 )
+            , fuzz2 (Fuzz.list Fuzz.string)
+                (Fuzz.list Fuzz.string)
+                "Only list + all except list = common types"
+                (\t1 t2 ->
+                    Expect.equal
+                        (Filter.and
+                            (Filter.onlyTypes t1)
+                            (Filter.allTypesExcept t2)
+                        )
+                        (Set.diff (Set.fromList t1) (Set.fromList t2)
+                            |> Set.toList
+                            |> Filter.onlyTypes
+                        )
+                )
+            , fuzz2 (Fuzz.list Fuzz.string)
+                (Fuzz.list Fuzz.string)
+                "Only list + all except list = common senders"
+                (\t1 t2 ->
+                    Expect.equal
+                        (Filter.and
+                            (Filter.onlySenders t1)
+                            (Filter.allSendersExcept t2)
+                        )
+                        (Set.diff (Set.fromList t1) (Set.fromList t2)
+                            |> Set.toList
+                            |> Filter.onlySenders
+                        )
+                )
+            ]
+        , describe "Subset testing"
+            [ fuzz2 fuzzer
+                fuzzer
+                "Combining two filters is always a subset"
+                (\filter1 filter2 ->
+                    filter1
+                        |> Filter.and filter2
+                        |> Expect.all
+                            [ Filter.subsetOf filter1 >> Expect.equal True
+                            , Filter.subsetOf filter2 >> Expect.equal True
+                            ]
+                )
+            , fuzz
+                (Fuzz.bool
+                    |> Fuzz.andThen
+                        (\same ->
+                            if same then
+                                Fuzz.map (\a -> ( a, a )) fuzzer
+
+                            else
+                                Fuzz.map2 Tuple.pair fuzzer fuzzer
+                        )
+                )
+                "subset goes both way iff equal"
+                (\( filter1, filter2 ) ->
+                    Expect.equal
+                        (filter1 == filter2)
+                        (Filter.subsetOf filter1 filter2
+                            && Filter.subsetOf filter2 filter1
+                        )
+                )
+            , fuzz2 Fuzz.string
+                (Fuzz.list Fuzz.string)
+                "One more excluded sender is a subset"
+                (\head tail ->
+                    Filter.allSendersExcept (head :: tail)
+                        |> Filter.subsetOf (Filter.allSendersExcept tail)
+                        |> Expect.equal True
+                )
+            , fuzz2 Fuzz.string
+                (Fuzz.list Fuzz.string)
+                "One more excluded type is a subset"
+                (\head tail ->
+                    Filter.allTypesExcept (head :: tail)
+                        |> Filter.subsetOf (Filter.allTypesExcept tail)
+                        |> Expect.equal True
+                )
+            , fuzz2 Fuzz.string
+                (Fuzz.list Fuzz.string)
+                "One less included sender is a subset"
+                (\head tail ->
+                    Filter.onlySenders tail
+                        |> Filter.subsetOf (Filter.onlySenders (head :: tail))
+                        |> Expect.equal True
+                )
+            , fuzz2 Fuzz.string
+                (Fuzz.list Fuzz.string)
+                "One less included type is a subset"
+                (\head tail ->
+                    Filter.onlyTypes tail
+                        |> Filter.subsetOf (Filter.onlyTypes (head :: tail))
+                        |> Expect.equal True
+                )
+            , fuzz3 Fuzz.string
+                (Fuzz.list Fuzz.string)
+                fuzzer
+                "One more excluded sender is a subset - even when combined with another fuzzer"
+                (\head tail filter ->
+                    Filter.allSendersExcept (head :: tail)
+                        |> Filter.and filter
+                        |> Filter.subsetOf (Filter.and filter <| Filter.allSendersExcept tail)
+                        |> Expect.equal True
+                )
+            , fuzz3 Fuzz.string
+                (Fuzz.list Fuzz.string)
+                fuzzer
+                "One more excluded type is a subset - even when combined with another fuzzer"
+                (\head tail filter ->
+                    Filter.allTypesExcept (head :: tail)
+                        |> Filter.and filter
+                        |> Filter.subsetOf (Filter.and filter <| Filter.allTypesExcept tail)
+                        |> Expect.equal True
+                )
+            , fuzz3 Fuzz.string
+                (Fuzz.list Fuzz.string)
+                fuzzer
+                "One less included sender is a subset - even when combined with another fuzzer"
+                (\head tail filter ->
+                    Filter.onlySenders tail
+                        |> Filter.and filter
+                        |> Filter.subsetOf (Filter.and filter <| Filter.onlySenders (head :: tail))
+                        |> Expect.equal True
+                )
+            , fuzz3 Fuzz.string
+                (Fuzz.list Fuzz.string)
+                fuzzer
+                "One less included type is a subset - even when combined with another fuzzer"
+                (\head tail filter ->
+                    Filter.onlyTypes tail
+                        |> Filter.and filter
+                        |> Filter.subsetOf (Filter.and filter <| Filter.onlyTypes (head :: tail))
+                        |> Expect.equal True
+                )
             ]
         , describe "Use case testing"
             [ fuzz3 (Fuzz.list TestEvent.fuzzer)
@@ -157,13 +290,12 @@ suite =
 
                         l2 : List Event.Event
                         l2 =
-                            ( List.filter
+                            List.filter
                                 (\e ->
-                                    (List.member e.sender senders) &&
+                                    List.member e.sender senders
-                                    (List.member e.eventType types)
+                                        && List.member e.eventType types
                                 )
                                 events
-                            )
                     in
                     Expect.all
                         [ Expect.equal (List.length l1) (List.length l2)
@@ -192,13 +324,12 @@ suite =
 
                         l2 : List Event.Event
                         l2 =
-                            ( List.filter
+                            List.filter
                                 (\e ->
-                                    (List.member e.sender senders) &&
+                                    List.member e.sender senders
-                                    (not <| List.member e.eventType types)
+                                        && (not <| List.member e.eventType types)
                                 )
                                 events
-                            )
                     in
                     Expect.all
                         [ Expect.equal (List.length l1) (List.length l2)
@@ -227,13 +358,12 @@ suite =
 
                         l2 : List Event.Event
                         l2 =
-                            ( List.filter
+                            List.filter
                                 (\e ->
-                                    (not <| List.member e.sender senders) &&
+                                    (not <| List.member e.sender senders)
-                                    (List.member e.eventType types)
+                                        && List.member e.eventType types
                                 )
                                 events
-                            )
                     in
                     Expect.all
                         [ Expect.equal (List.length l1) (List.length l2)
@@ -262,13 +392,12 @@ suite =
 
                         l2 : List Event.Event
                         l2 =
-                            ( List.filter
+                            List.filter
                                 (\e ->
-                                    (not <| List.member e.sender senders) &&
+                                    (not <| List.member e.sender senders)
-                                    (not <| List.member e.eventType types)
+                                        && (not <| List.member e.eventType types)
                                 )
                                 events
-                            )
                     in
                     Expect.all
                         [ Expect.equal (List.length l1) (List.length l2)

tests/Test/Values/Event.elm

@@ -1,11 +1,11 @@
 module Test.Values.Event exposing (..)
 
+import Expect
 import Fuzz exposing (Fuzzer)
 import Internal.Values.Event as Event exposing (Event)
 import Json.Encode as E
 import Test exposing (..)
 import Test.Tools.Timestamp as TestTimestamp
-import Expect
 
 
 fuzzer : Fuzzer Event
@@ -67,10 +67,12 @@ valueFuzzer =
         , Fuzz.map Event.encode (Fuzz.lazy (\_ -> fuzzer))
         ]
 
+
 suite : Test
 suite =
     describe "Sanity check"
-        [ fuzz fuzzer "event = event"
+        [ fuzz fuzzer
+            "event = event"
             (\event ->
                 Event.isEqual event event
                     |> Expect.equal True