requirements analysis for literal argument to use

src/swarm-lang/Swarm/Language/Requirements/Analysis.hs

@@ -101,9 +101,11 @@ requirements tdCtx ctx =
       add (singletonCap CLambda)
       mapM_ typeRequirements mty
       local @ReqCtx (Ctx.delete x) $ go t
-    -- An application simply requires the union of the capabilities
-    -- from the left- and right-hand sides.  This assumes that the
-    -- argument will be used at least once by the function.
+    -- Special case for 'use' with a device literal.
+    TApp (TConst Use) (TText device) -> add (singletonDev device)
+    -- In general, an application simply requires the union of the
+    -- capabilities from the left- and right-hand sides.  This assumes
+    -- that the argument will be used at least once by the function.
     TApp t1 t2 -> go t1 *> go t2
     -- Similarly, for a let, we assume that the let-bound expression
     -- will be used at least once in the body. We delete the let-bound

test/unit/TestRequirements.hs

@@ -39,6 +39,11 @@ testRequirements =
               "def m = move end; def y = \\m. log (format m) end"
               (maybe False ((CExecute Move `S.notMember`) . capReqs) . Ctx.lookup "y")
         ]
+    , testGroup
+        "use"
+        [ testCase "literal argument to use (#1301)" $
+            "use \"key\"" `requiresDev` "key"
+        ]
     ]
 
 checkReqCtx :: Text -> (ReqCtx -> Bool) -> Assertion
@@ -49,3 +54,6 @@ checkRequirements code expect = check code (expect . requirements mempty mempty
 
 requiresCap :: Text -> Capability -> Assertion
 requiresCap code cap = checkRequirements code ((cap `S.member`) . capReqs)
+
+requiresDev :: Text -> Text -> Assertion
+requiresDev code dev = checkRequirements code ((dev `S.member`) . capDevs)