address some review comments

src/Swarm/Game/Scenario/Cell.hs

@@ -41,14 +41,16 @@ data PCell e = Cell
 --   and optionally an entity and robot.
 type Cell = PCell Entity
 
+mkPCellJson :: ToJSON b => (a -> b) -> PCell a -> Value
+mkPCellJson modifier x = toJSON $
+  catMaybes
+    [ Just . toJSON . getTerrainWord $ cellTerrain x
+    , toJSON . modifier <$> cellEntity x
+    , listToMaybe []
+    ]
+
 instance ToJSON Cell where
-  toJSON x =
-    toJSON $
-      catMaybes
-        [ Just $ toJSON $ getTerrainWord $ cellTerrain x
-        , toJSON . (^. entityName) <$> cellEntity x
-        , listToMaybe []
-        ]
+  toJSON = mkPCellJson $ view entityName
 
 -- | Parse a tuple such as @[grass, rock, base]@ into a 'Cell'.  The
 --   entity and robot, if present, are immediately looked up and
@@ -83,10 +85,4 @@ type CellPaintDisplay = PCell EntityFacade
 
 -- Note: This instance is used only for the purpose of WorldPalette
 instance ToJSON CellPaintDisplay where
-  toJSON x =
-    toJSON $
-      catMaybes
-        [ Just $ toJSON $ getTerrainWord $ cellTerrain x
-        , toJSON <$> cellEntity x
-        , listToMaybe []
-        ]
+  toJSON = mkPCellJson id

src/Swarm/Game/Scenario/EntityFacade.hs

@@ -1,5 +1,11 @@
 {-# LANGUAGE DerivingVia #-}
 
+-- | Stand-in type for an "Entity" for purposes
+-- that do not require carrying around the entire state
+-- of an Entity.
+--
+-- Useful for simplified serialization, debugging,
+-- and equality checking, particularly for the World Editor.
 module Swarm.Game.Scenario.EntityFacade where
 
 import Control.Lens hiding (from, (.=), (<.>))
@@ -10,15 +16,18 @@ import Swarm.Game.Entity qualified as E
 
 type EntityName = Text
 
+-- | This datatype is a lightweight stand-in for the
+-- full-fledged "Entity" type without the baggage of all
+-- of its other fields.
 data EntityFacade = EntityFacade EntityName Display
   deriving (Eq)
 
 -- Note: This instance is used only for the purpose of WorldPalette
 instance ToJSON EntityFacade where
   toJSON (EntityFacade eName _display) = toJSON eName
 
-mkPaint :: E.Entity -> EntityFacade
-mkPaint e =
+mkFacade :: E.Entity -> EntityFacade
+mkFacade e =
   EntityFacade
     (e ^. E.entityName)
     (e ^. E.entityDisplay)

src/Swarm/Game/Scenario/WorldDescription.hs

@@ -88,7 +88,7 @@ cellToTerrainEntityNamePair (Cell terrain maybeEntity _) = (terrain, maybeEntity
 
 toCellPaintDisplay :: Cell -> CellPaintDisplay
 toCellPaintDisplay (Cell terrain maybeEntity r) =
-  Cell terrain (mkPaint <$> maybeEntity) r
+  Cell terrain (mkFacade <$> maybeEntity) r
 
 type WorldDescriptionPaint = PWorldDescription EntityFacade
 

src/Swarm/Game/State.hs

@@ -188,7 +188,6 @@ import Swarm.Language.Syntax (Const, SrcLoc (..), Syntax' (..), allConst)
 import Swarm.Language.Typed (Typed (Typed))
 import Swarm.Language.Types
 import Swarm.Language.Value (Value)
-import Swarm.TUI.Editor.Model (BoundsRectangle)
 import Swarm.Util (uniq, (<+=), (<<.=), (?))
 import System.Clock qualified as Clock
 import System.Random (StdGen, mkStdGen, randomRIO)
@@ -737,7 +736,7 @@ unfocus = (\g -> g {_focusedRobotID = -1000}) . modifyViewCenter id
 
 -- | Given a width and height, compute the region, centered on the
 --   'viewCenter', that should currently be in view.
-viewingRegion :: GameState -> (Int32, Int32) -> BoundsRectangle
+viewingRegion :: GameState -> (Int32, Int32) -> W.BoundsRectangle
 viewingRegion g (w, h) = (W.Coords (rmin, cmin), W.Coords (rmax, cmax))
  where
   Location cx cy = g ^. viewCenter

src/Swarm/Game/World.hs

@@ -17,7 +17,8 @@ module Swarm.Game.World (
   Coords (..),
   locToCoords,
   coordsToLoc,
-
+  BoundsRectangle,
+
   -- * Worlds
   WorldFun (..),
   worldFunFromArray,
@@ -87,6 +88,11 @@ locToCoords (Location x y) = Coords (-y, x)
 coordsToLoc :: Coords -> Location
 coordsToLoc (Coords (r, c)) = Location c (-r)
 
+
+-- | Represents the top-left and bottom-right coordinates
+-- of a bounding rectangle of cells in the world map
+type BoundsRectangle = (Coords, Coords)
+
 ------------------------------------------------------------
 -- World function
 ------------------------------------------------------------

src/Swarm/TUI/Controller.hs

@@ -442,14 +442,10 @@ handleModalEvent = \case
     Brick.zoom (uiState . uiModal . _Just . modalDialog) (handleDialogEvent ev)
     modal <- preuse $ uiState . uiModal . _Just . modalType
     case modal of
-      Just TerrainPaletteModal -> do
-        lw <- use $ uiState . uiWorldEditor . terrainList
-        newList <- refreshList lw
-        uiState . uiWorldEditor . terrainList .= newList
+      Just TerrainPaletteModal ->
+        refreshList $ uiState . uiWorldEditor . terrainList
       Just EntityPaletteModal -> do
-        lw <- use $ uiState . uiWorldEditor . entityPaintList
-        newList <- refreshList lw
-        uiState . uiWorldEditor . entityPaintList .= newList
+        refreshList $ uiState . uiWorldEditor . entityPaintList
       Just GoalModal -> case ev of
         V.EvKey (V.KChar '\t') [] -> uiState . uiGoal . focus %= focusNext
         _ -> do
@@ -465,7 +461,7 @@ handleModalEvent = \case
       _ -> handleInfoPanelEvent modalScroll (VtyEvent ev)
    where
     refreshGoalList lw = nestEventM' lw $ handleListEventWithSeparators ev shouldSkipSelection
-    refreshList w = nestEventM' w $ BL.handleListEvent ev
+    refreshList z = Brick.zoom z $ BL.handleListEvent ev
 
 getNormalizedCurrentScenarioPath :: (MonadIO m, MonadState AppState m) => m (Maybe FilePath)
 getNormalizedCurrentScenarioPath =

src/Swarm/TUI/Editor/Controller.hs

@@ -111,7 +111,7 @@ handleMiddleClick mouseLoc = do
              where
               p = case elementPaint of
                 Facade efd -> efd
-                Ref r -> mkPaint r
+                Ref r -> mkFacade r
 
     mouseCoordsM <- Brick.zoom gameState $ mouseLocToWorldCoords mouseLoc
     whenJust mouseCoordsM setTerrainPaint

src/Swarm/TUI/Editor/Model.hs

@@ -18,10 +18,6 @@ import Swarm.TUI.Model.Name
 import Swarm.Util
 import System.Clock
 
--- | Represents the top-left and bottom-right coordinates
--- of a bounding rectangle of cells in the world map
-type BoundsRectangle = (W.Coords, W.Coords)
-
 data BoundsSelectionStep
   = UpperLeftPending
   | -- | Stores the *world coords* of the upper-left click
@@ -40,13 +36,13 @@ getDisplay (Ref e) = e ^. E.entityDisplay
 toFacade :: EntityPaint -> EntityFacade
 toFacade = \case
   Facade f -> f
-  Ref e -> mkPaint e
+  Ref e -> mkFacade e
 
 getEntityName :: EntityFacade -> EntityName
 getEntityName (EntityFacade name _) = name
 
 data MapEditingBounds = MapEditingBounds
-  { _boundsRect :: Maybe BoundsRectangle
+  { _boundsRect :: Maybe W.BoundsRectangle
   -- ^ Upper-left and lower-right coordinates
   -- of the map to be saved.
   , _boundsPersistDisplayUntil :: TimeSpec

src/Swarm/TUI/Editor/Util.hs

@@ -20,11 +20,11 @@ import Swarm.TUI.Model
 
 getEntitiesForList :: EntityMap -> V.Vector EntityFacade
 getEntitiesForList em =
-  V.fromList $ map mkPaint entities
+  V.fromList $ map mkFacade entities
  where
   entities = M.elems $ entitiesByName em
 
-getEditingBounds :: WorldDescription -> (Bool, BoundsRectangle)
+getEditingBounds :: WorldDescription -> (Bool, W.BoundsRectangle)
 getEditingBounds myWorld =
   (EA.isEmpty a, newBounds)
  where
@@ -86,7 +86,7 @@ isOutsideBottomRightCorner (W.Coords (yBottom, xRight)) (W.Coords (y, x)) =
 
 isOutsideRegion ::
   -- | full bounds
-  BoundsRectangle ->
+  W.BoundsRectangle ->
   -- | current coords
   W.Coords ->
   Bool
@@ -95,7 +95,7 @@ isOutsideRegion (tl, br) coord =
 
 getEditedMapRectangle ::
   WorldEditor Name ->
-  Maybe BoundsRectangle ->
+  Maybe W.BoundsRectangle ->
   W.World Int Entity ->
   [[CellPaintDisplay]]
 getEditedMapRectangle _ Nothing _ = []

src/Swarm/TUI/View/CellDisplay.hs

@@ -1,6 +1,8 @@
 {-# LANGUAGE OverloadedStrings #-}
 
 -- |
+-- Rendering of cells in the map view
+-- 
 -- SPDX-License-Identifier: BSD-3-Clause
 module Swarm.TUI.View.CellDisplay where
 
@@ -87,7 +89,8 @@ hidingMode g
 --   taking into account "static" based on the distance to the robot
 --   being @view@ed.
 displayLoc :: Bool -> WorldEditor Name -> GameState -> W.Coords -> Display
-displayLoc showRobots we g coords = staticDisplay g coords <> displayLocRaw showRobots we g coords
+displayLoc showRobots we g coords = staticDisplay g coords
+  <> displayLocRaw showRobots we g coords
 
 -- | Get the 'Display' for a specific location, by combining the
 --   'Display's for the terrain, entity, and robots at the location.