use weeder

.github/workflows/weeder.yml

@@ -0,0 +1,26 @@
+name: Dead code
+on:
+  push:
+    paths:
+      - '**.hs'
+      - '**.cabal'
+    branches:
+      - main
+  pull_request:
+    paths:
+      - '**.hs'
+      - '**.cabal'
+    branches:
+      - main
+jobs:
+  gild:
+    name: Weeder
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install weeder
+        run: |
+          cabal update
+          cabal install weeder
+      - run: |
+          scripts/validate/weeder.sh

scripts/validate/weeder.sh

@@ -0,0 +1,10 @@
+
+
+# First, install Weeder:
+#   cabal install weeder
+
+cabal clean
+cabal build -O0 -j all
+
+weeder -N
+

src/swarm-engine/Swarm/Game/Scenario/Status.hs

@@ -67,9 +67,6 @@ instance ToJSON ScenarioStatus where
   toEncoding = genericToEncoding scenarioOptions
   toJSON = genericToJSON scenarioOptions
 
-seedLaunchParams :: Applicative f => Maybe Seed -> ParameterizableLaunchParams a f
-seedLaunchParams s = LaunchParams (pure s) (pure Nothing)
-
 emptyLaunchParams :: Applicative f => ParameterizableLaunchParams a f
 emptyLaunchParams = LaunchParams (pure Nothing) (pure Nothing)
 

src/swarm-scenario/Swarm/Game/Scenario/Objective/Graph.hs

@@ -53,11 +53,6 @@ instance ToSample GraphInfo where
 deriving instance Generic (BE.Signed ObjectiveLabel)
 deriving instance ToJSON (BE.Signed ObjectiveLabel)
 
-getConstFromSigned :: BE.Signed a -> a
-getConstFromSigned = \case
-  BE.Positive x -> x
-  BE.Negative x -> x
-
 getDistinctConstants :: (Ord a) => Prerequisite a -> Set (BE.Signed a)
 getDistinctConstants = Set.fromList . BE.constants . toBoolExpr
 

src/swarm-topography/Swarm/Game/Location.hs

@@ -20,7 +20,6 @@ module Swarm.Game.Location (
   toDirection,
   toAbsDirection,
   nearestDirection,
-  fromDirection,
   isCardinal,
   north,
   south,
@@ -192,14 +191,6 @@ nearestDirection coord =
   index = round $ fromIntegral (length orderedDirs) * angle
   orderedDirs = Util.enumerateNonEmpty
 
--- | Convert a 'Direction' into a corresponding 'Heading'.  Note that
---   this only does something reasonable for 'DNorth', 'DSouth', 'DEast',
---   and 'DWest'---other 'Direction's return the zero vector.
-fromDirection :: Direction -> Heading
-fromDirection = \case
-  DAbsolute x -> toHeading x
-  _ -> zero
-
 -- | Manhattan distance between world locations.
 manhattan :: Location -> Location -> Int32
 manhattan (Location x1 y1) (Location x2 y2) = abs (x1 - x2) + abs (y1 - y2)

src/swarm-tui/Swarm/TUI/Editor/Model.hs

@@ -41,9 +41,6 @@ toFacade = \case
   Facade f -> f
   Ref e -> mkFacade e
 
-getEntityName :: EntityFacade -> E.EntityName
-getEntityName (EntityFacade name _) = name
-
 data MapEditingBounds = MapEditingBounds
   { _boundsRect :: Maybe (Cosmic BoundsRectangle)
   -- ^ Upper-left and lower-right coordinates

swarm.cabal

@@ -85,7 +85,6 @@ common common
 common stan-config
   ghc-options:
     -fwrite-ide-info
-    -hiedir=.hie
 
 -- Harmless extensions from GHC2021
 common ghc2021-extensions
@@ -199,6 +198,9 @@ library swarm-lang
 
   build-depends: swarm:swarm-util
   hs-source-dirs: src/swarm-lang
+  ghc-options:
+    -hiedir=.hie/src/swarm-lang
+
   default-language: Haskell2010
   default-extensions:
     -- Avoid unexpected unevaluated thunk buildup
@@ -253,6 +255,9 @@ library swarm-topography
     swarm:swarm-util
 
   hs-source-dirs: src/swarm-topography
+  ghc-options:
+    -hiedir=.hie/src/swarm-topography
+
   default-language: Haskell2010
   default-extensions:
     -- Avoid unexpected unevaluated thunk buildup
@@ -351,6 +356,9 @@ library swarm-scenario
     swarm:swarm-util,
 
   hs-source-dirs: src/swarm-scenario
+  ghc-options:
+    -hiedir=.hie/src/swarm-scenario
+
   default-language: Haskell2010
   default-extensions:
     -- Avoid unexpected unevaluated thunk buildup
@@ -451,6 +459,9 @@ library swarm-engine
     swarm:swarm-util,
 
   hs-source-dirs: src/swarm-engine
+  ghc-options:
+    -hiedir=.hie/src/swarm-engine
+
   default-language: Haskell2010
   default-extensions:
     -- Avoid unexpected unevaluated thunk buildup
@@ -497,6 +508,9 @@ library swarm-web
     swarm:swarm-util,
 
   hs-source-dirs: src/swarm-web
+  ghc-options:
+    -hiedir=.hie/src/swarm-web
+
   default-language: Haskell2010
   default-extensions:
     -- Avoid unexpected unevaluated thunk buildup
@@ -555,6 +569,9 @@ library swarm-tournament
     swarm:swarm-util,
 
   hs-source-dirs: src/swarm-tournament
+  ghc-options:
+    -hiedir=.hie/src/swarm-tournament
+
   default-language: Haskell2010
 
 library swarm-util
@@ -604,6 +621,9 @@ library swarm-util
     yaml >=0.11 && <0.11.12.0,
 
   hs-source-dirs: src/swarm-util
+  ghc-options:
+    -hiedir=.hie/src/swarm-util
+
   default-language: Haskell2010
   default-extensions:
     -- Avoid unexpected unevaluated thunk buildup
@@ -655,6 +675,9 @@ library swarm-doc
     swarm:swarm-util,
 
   hs-source-dirs: src/swarm-doc
+  ghc-options:
+    -hiedir=.hie/src/swarm-doc
+
   default-language: Haskell2010
   default-extensions:
     -- Avoid unexpected unevaluated thunk buildup
@@ -761,14 +784,17 @@ library swarm-tui
     swarm:swarm-util,
 
   hs-source-dirs: src/swarm-tui
+  ghc-options:
+    -hiedir=.hie/src/swarm-tui
+
   default-language: Haskell2010
   default-extensions:
     -- Avoid unexpected unevaluated thunk buildup
     -- See discussion in #415
     StrictData
 
 executable swarm
-  import: stan-config, common
+  import: stan-config, common, ghc2021-extensions
   main-is: Main.hs
   other-modules: Swarm.App
   build-depends:
@@ -789,7 +815,10 @@ executable swarm
     vty,
     vty-crossplatform >=0.4 && <0.5,
 
-  hs-source-dirs: app
+  hs-source-dirs: app/game
+  ghc-options:
+    -hiedir=.hie/app/game
+
   default-language: Haskell2010
   ghc-options: -threaded
   default-extensions: ImportQualifiedPost
@@ -806,6 +835,9 @@ executable swarm-scene
     swarm:swarm-topography,
 
   hs-source-dirs: app/scene
+  ghc-options:
+    -hiedir=.hie/app/scene
+
   default-language: Haskell2010
   ghc-options: -threaded
   default-extensions: ImportQualifiedPost
@@ -822,6 +854,9 @@ executable swarm-docs
     text,
 
   hs-source-dirs: app/doc
+  ghc-options:
+    -hiedir=.hie/app/doc
+
   default-language: Haskell2010
   ghc-options: -threaded
   default-extensions: ImportQualifiedPost
@@ -842,6 +877,9 @@ executable swarm-host-tournament
     swarm:swarm-tournament,
 
   hs-source-dirs: app/tournament
+  ghc-options:
+    -hiedir=.hie/app/tournament
+
   default-language: Haskell2010
   ghc-options: -threaded
   default-extensions: ImportQualifiedPost
@@ -899,6 +937,9 @@ test-suite swarm-unit
     swarm:swarm-util,
 
   hs-source-dirs: test/unit
+  ghc-options:
+    -hiedir=.hie/test/unit
+
   default-language: Haskell2010
   ghc-options: -threaded
 
@@ -931,6 +972,9 @@ test-suite swarm-integration
     swarm:swarm-util,
 
   hs-source-dirs: test/integration
+  ghc-options:
+    -hiedir=.hie/test/integration
+
   default-language: Haskell2010
   ghc-options: -threaded
 
@@ -954,6 +998,9 @@ test-suite tournament-host
     swarm:swarm-tournament,
 
   hs-source-dirs: test/tournament-host
+  ghc-options:
+    -hiedir=.hie/test/tournament-host
+
   default-language: Haskell2010
   ghc-options: -threaded
 
@@ -982,13 +1029,19 @@ test-suite standalone-topography
     swarm:swarm-util,
 
   hs-source-dirs: test/standalone-topography/src
+  ghc-options:
+    -hiedir=.hie/test/standalone-topography/src
+
   default-language: Haskell2010
   ghc-options: -threaded
 
 benchmark benchmark
   import: stan-config, common, ghc2021-extensions
   main-is: Benchmark.hs
   hs-source-dirs: test/bench
+  ghc-options:
+    -hiedir=.hie/test/bench
+
   type: exitcode-stdio-1.0
   build-depends:
     base,

weeder.toml

@@ -0,0 +1,70 @@
+roots = [
+    "^Main.main$",
+    "^Paths_.*",
+
+    # Workarounds for TH parsing:
+    # -------------------------------
+    "^Swarm.Language.Pipeline.QQ.tmQ$",
+    "^Swarm.Language.Parser.QQ.tyQ$",
+    "^Swarm.Util.Lens.makeLensesNoSigs$",
+    "^Swarm.Util.Lens.makeLensesExcluding$",
+
+    # Workarounds for type families:
+    # -------------------------------
+    "^Swarm.Game.World.Compile.NoFunParams$",
+
+    # True positives:
+    # =====================================
+    "^Main.prop_hittingSetMinimal$",
+    "^Main.printAllLogs$",
+    "^Control.Carrier.Accum.FixedStrict.execAccum$",
+#    "^Swarm.App.demoWeb$",
+    "^Swarm.Effect.Unify.Common.dom$",
+    "^Swarm.Effect.Unify.Fast.@@$",
+    "^Swarm.Effect.Unify.Naive.runUnification$",
+    "^Swarm.Game.Entity.entityNameFor$",
+    "^Swarm.Game.Entity.singleton$",
+    "^Swarm.Game.Entity.Cosmetic.getBackground$",
+    "^Swarm.Game.Step.traceLogShow$",
+    "^Swarm.Game.World.Compile.compile$",
+    "^Swarm.Game.World.Compile.runCTerm$",
+    "^Swarm.Game.World.lookupTerrainM$",
+    "^Swarm.Language.Context.withBindings$",
+    "^Swarm.Language.Context.singleton$",
+    "^Swarm.Language.Parser.Util.showShortError$",
+    "^Swarm.Language.Pipeline.extractTCtx$",
+    "^Swarm.Language.Pretty.Prec$",
+    "^Swarm.Language.Pretty.appliedTermPrec$",
+    "^Swarm.Language.Requirements.Type.insert$",
+    "^Swarm.Language.Syntax.Pattern.UTerm$",
+    "^Swarm.Language.Syntax.Util.asTree$",
+    "^Swarm.Language.Syntax.Util.mapFreeS$",
+    "^Swarm.Util.replaceLast$",
+    "^Swarm.Util.reflow$",
+    "^Swarm.Util.isSuccessOr$",
+    "^Swarm.Util._NonEmpty$",
+
+    # True positives (unused lenses):
+    # -------------------------------
+    "^Swarm.Language.Typed.polytype$",
+    "^Swarm.Language.Typed.requires$",
+    "^Swarm.Language.Typed.value$",
+    "^Swarm.Language.Value.emptyEnv$",
+    "^Swarm.Game.Scenario.staticPlacements$",
+    "^Swarm.Game.Scenario.structureDefs$",
+    "^Swarm.Game.Scenario.Scoring.Best.scenarioBestByAstSize$",
+    "^Swarm.Game.Scenario.Scoring.Best.scenarioBestByCharCount$",
+    "^Swarm.Game.Scenario.Scoring.Best.scenarioBestByTicks$",
+    "^Swarm.Game.Scenario.Scoring.Best.scenarioBestByTime$",
+    "^Swarm.Game.ScenarioInfo._NotStarted$",
+    "^Swarm.Game.ScenarioInfo._Played$",
+    "^Swarm.Game.State.Robot._VCLocation$",
+    "^Swarm.Game.State.Robot._VCRobot$",
+    "^Swarm.Game.State.Substate._NoWinCondition$",
+    "^Swarm.Game.State.Substate._WinConditions$",
+
+    ]
+
+type-class-roots = true
+unused-types = true
+