Fixes around incomplete guards (#20023, #20024)wip/runtime-error-fixes

- Fix linearity error with incomplete MultiWayIf (#20023)
- Fix partial pattern binding error message (#20024)
- Remove obsolete test LinearPolyTest
  It tested the special typing rule for ($), which was removed
  during the implementation of Quick Look 97cff9190d3.
- Fix ticket numbers in linear/*/all.T, they referred to linear types
  issue tracker

2 files changed, 6 insertions, 13 deletions

diff --git a/compiler/GHC/Tc/Errors.hs b/compiler/GHC/Tc/Errors.hs
index f3c8a19b04..e45d051e50 100644
--- a/compiler/GHC/Tc/Errors.hs
+++ b/compiler/GHC/Tc/Errors.hs
@@ -953,10 +953,10 @@ mkErrorTerm ctxt ct_loc ty report
          -- This will be reported at runtime, so we always want "error:" in the report, never "warning:"
        ; dflags <- getDynFlags
        ; let err_msg = pprLocMsgEnvelope msg
-             err_fs  = mkFastString $ showSDoc dflags $
+             err_str = showSDoc dflags $
                        err_msg $$ text "(deferred type error)"
 
-       ; return $ evDelayedError ty err_fs }
+       ; return $ evDelayedError ty err_str }
 
 tryReporters :: ReportErrCtxt -> [ReporterSpec] -> [Ct] -> TcM (ReportErrCtxt, [Ct])
 -- Use the first reporter in the list whose predicate says True
diff --git a/compiler/GHC/Tc/Types/EvTerm.hs b/compiler/GHC/Tc/Types/EvTerm.hs
index 19afec031a..ad380ec0a2 100644
--- a/compiler/GHC/Tc/Types/EvTerm.hs
+++ b/compiler/GHC/Tc/Types/EvTerm.hs
@@ -13,34 +13,27 @@ import GHC.Tc.Types.Evidence
 import GHC.Unit
 
 import GHC.Builtin.Names
-import GHC.Builtin.Types ( liftedRepTy, unitTy )
+import GHC.Builtin.Types ( unitTy )
 
 import GHC.Core.Type
 import GHC.Core
 import GHC.Core.Make
 import GHC.Core.Utils
 
-import GHC.Types.Literal ( Literal(..) )
 import GHC.Types.SrcLoc
 import GHC.Types.Name
 import GHC.Types.TyThing
 
-import GHC.Data.FastString
-
 -- Used with Opt_DeferTypeErrors
 -- See Note [Deferring coercion errors to runtime]
 -- in GHC.Tc.Solver
-evDelayedError :: Type -> FastString -> EvTerm
+evDelayedError :: Type -> String -> EvTerm
 evDelayedError ty msg
   = EvExpr $
-    let fail_expr = Var errorId `mkTyApps` [liftedRepTy, unitTy] `mkApps` [litMsg]
+    let fail_expr = mkRuntimeErrorApp tYPE_ERROR_ID unitTy msg
     in mkWildCase fail_expr (unrestricted unitTy) ty []
        -- See Note [Incompleteness and linearity] in GHC.HsToCore.Utils
-       -- c.f. mkFailExpr in GHC.HsToCore.Utils
-
-  where
-    errorId = tYPE_ERROR_ID
-    litMsg  = Lit (LitString (bytesFS msg))
+       -- c.f. mkErrorAppDs in GHC.HsToCore.Utils
 
 -- Dictionary for CallStack implicit parameters
 evCallStack :: (MonadThings m, HasModule m, HasDynFlags m) =>