trivial doc improvement and unused name fix

cabal-install/Hackage/InstallPlan.hs

@@ -261,8 +261,8 @@ lookupConfiguredPackage' :: InstallPlan a
                          -> PackageIdentifier -> Maybe ConfiguredPackage
 lookupConfiguredPackage' plan pkgid =
   case PackageIndex.lookupPackageId (planIndex plan) pkgid of
-    Just (Configured pkg)  -> Just pkg
-    Just (Failed _ reason) -> Nothing
+    Just (Configured pkg) -> Just pkg
+    Just (Failed _ _)     -> Nothing
     _  -> internalError $ "not configured or no such pkg " ++ display pkgid
 
 -- ------------------------------------------------------------

cabal-install/Hackage/Types.hs

@@ -29,8 +29,10 @@ newtype Password = Password { unPassword :: String }
 data ConfiguredPackage = ConfiguredPackage
        AvailablePackage    -- package info, including repo
        FlagAssignment      -- complete flag assignment for the package
-       [PackageIdentifier] -- exact dependencies, must be consistent with the
-                           -- version constraints in the package info
+       [PackageIdentifier] -- set of exact dependencies. These must be
+                           -- consistent with the 'buildDepends' in the
+                           -- 'PackageDescrption' that you'd get by applying
+                           -- the flag assignment.
   deriving Show
 
 instance Package ConfiguredPackage where