unit test for recipe coverage (#1676)

Towards #1268

## Demo

    scripts/run-tests.sh --test-arguments '--pattern "Recipe coverage"'

swarm.cabal

@@ -439,6 +439,7 @@ test-suite swarm-unit
                       TestInventory
                       TestModel
                       TestPedagogy
+                      TestRecipeCoverage
                       TestNotification
                       TestLanguagePipeline
                       TestOrdering
@@ -451,6 +452,7 @@ test-suite swarm-unit
 
     build-depends:    tasty                         >= 0.10 && < 1.6,
                       tasty-hunit                   >= 0.10 && < 0.11,
+                      tasty-expected-failure        >= 0.12 && < 0.13,
                       tasty-quickcheck              >= 0.10 && < 0.11,
                       QuickCheck                    >= 2.14 && < 2.15,
                       -- Imports shared with the library don't need bounds

test/unit/Main.hs

@@ -37,6 +37,7 @@ import TestNotification (testNotification)
 import TestOrdering (testOrdering)
 import TestPedagogy (testPedagogy)
 import TestPretty (testPrettyConst)
+import TestRecipeCoverage (testDeviceRecipeCoverage)
 import TestScoring (testHighScores)
 import Witch (from)
 
@@ -55,6 +56,7 @@ tests s =
     , testPrettyConst
     , testBoolExpr
     , testCommands
+    , testDeviceRecipeCoverage (s ^. runtimeState)
     , testHighScores
     , testEval (s ^. gameState)
     , testModel

test/unit/TestRecipeCoverage.hs

@@ -0,0 +1,48 @@
+{-# LANGUAGE OverloadedStrings #-}
+
+-- |
+-- SPDX-License-Identifier: BSD-3-Clause
+--
+-- Ensure recipe coverage for all entities that
+-- grant capabilities (aka "devices").
+module TestRecipeCoverage where
+
+import Control.Lens ((^.))
+import Data.Map qualified as M
+import Data.Set qualified as Set
+import Data.Text qualified as T
+import Swarm.Game.Entity (EntityMap (entitiesByCap), entityName)
+import Swarm.Game.Recipe (recipeOutputs)
+import Swarm.TUI.Model (RuntimeState, stdEntityMap, stdRecipes)
+import Swarm.Util (commaList, quote)
+import Test.Tasty
+import Test.Tasty.ExpectedFailure (expectFailBecause)
+import Test.Tasty.HUnit
+
+testDeviceRecipeCoverage :: RuntimeState -> TestTree
+testDeviceRecipeCoverage rs =
+  testGroup
+    "Recipe coverage"
+    [ expectFailBecause "Need to come up with more recipes" checkCoverage
+    ]
+ where
+  checkCoverage :: TestTree
+  checkCoverage =
+    testCase
+      "Ensure all devices have recipes (#1268)"
+      $ assertBool errMessage
+      $ null nonCoveredEntities
+   where
+    errMessage =
+      T.unpack $
+        T.unwords
+          [ "Missing recipes for:"
+          , commaList $ map quote $ Set.toList nonCoveredEntities
+          ]
+
+    -- Only include entities that grant a capability:
+    entityNames = Set.fromList . map (^. entityName) . concat . M.elems . entitiesByCap $ rs ^. stdEntityMap
+
+    getOutputsForRecipe r = map ((^. entityName) . snd) $ r ^. recipeOutputs
+    recipeOutputEntities = Set.fromList . concatMap getOutputsForRecipe $ rs ^. stdRecipes
+    nonCoveredEntities = Set.difference entityNames recipeOutputEntities