Dot/bang operators in export lists (Trac #16339)

The dot type operator was handled in the 'tyvarop' parser production, and the
bang type operator in 'tyapp'. However, export lists and role annotations use
'oqtycon', so these type operators could not be exported or assigned roles.

The fix is to handle them in a lower level production, 'tyconsym'.

4 files changed, 29 insertions, 5 deletions

diff --git a/compiler/parser/Parser.y b/compiler/parser/Parser.y
index 78f1013151..544d9d76e4 100644
--- a/compiler/parser/Parser.y
+++ b/compiler/parser/Parser.y
@@ -1989,14 +1989,15 @@ tyapps :: { [Located TyEl] } -- NB: This list is reversed
 tyapp :: { Located TyEl }
         : atype                         { sL1 $1 $ TyElOpd (unLoc $1) }
         | TYPEAPP atype                 { sLL $1 $> $ (TyElKindApp (comb2 $1 $2) $2) }
-        | qtyconop                      { sL1 $1 $ TyElOpr (unLoc $1) }
+        | qtyconop                      { sL1 $1 $ if isBangRdr (unLoc $1)
+                                                   then TyElBang
+                                                   else TyElOpr (unLoc $1) }
         | tyvarop                       { sL1 $1 $ TyElOpr (unLoc $1) }
         | SIMPLEQUOTE qconop            {% ams (sLL $1 $> $ TyElOpr (unLoc $2))
                                                [mj AnnSimpleQuote $1,mj AnnVal $2] }
         | SIMPLEQUOTE varop             {% ams (sLL $1 $> $ TyElOpr (unLoc $2))
                                                [mj AnnSimpleQuote $1,mj AnnVal $2] }
         | '~'                           { sL1 $1 TyElTilde }
-        | '!'                           { sL1 $1 TyElBang }
         | unpackedness                  { sL1 $1 $ TyElUnpackedness (unLoc $1) }
 
 atype :: { LHsType GhcPs }
@@ -3310,13 +3311,13 @@ qtyconsym :: { Located RdrName }
         | QVARSYM            { sL1 $1 $! mkQual tcClsName (getQVARSYM $1) }
         | tyconsym           { $1 }
 
--- Does not include "!", because that is used for strictness marks
---               or ".", because that separates the quantified type vars from the rest
 tyconsym :: { Located RdrName }
         : CONSYM                { sL1 $1 $! mkUnqual tcClsName (getCONSYM $1) }
         | VARSYM                { sL1 $1 $! mkUnqual tcClsName (getVARSYM $1) }
         | ':'                   { sL1 $1 $! consDataCon_RDR }
         | '-'                   { sL1 $1 $! mkUnqual tcClsName (fsLit "-") }
+        | '!'                   { sL1 $1 $! mkUnqual tcClsName (fsLit "!") }
+        | '.'                   { sL1 $1 $! mkUnqual tcClsName (fsLit ".") }
 
 
 -----------------------------------------------------------------------------
@@ -3371,7 +3372,6 @@ tyvarop :: { Located RdrName }
 tyvarop : '`' tyvarid '`'       {% ams (sLL $1 $> (unLoc $2))
                                        [mj AnnBackquote $1,mj AnnVal $2
                                        ,mj AnnBackquote $3] }
-        | '.'                   { sL1 $1 $ mkUnqual tcClsName (fsLit ".") }
 
 tyvarid :: { Located RdrName }
         : VARID            { sL1 $1 $! mkUnqual tvName (getVARID $1) }
diff --git a/compiler/parser/RdrHsSyn.hs b/compiler/parser/RdrHsSyn.hs
index 606e2e7d6b..c65b814529 100644
--- a/compiler/parser/RdrHsSyn.hs
+++ b/compiler/parser/RdrHsSyn.hs
@@ -49,6 +49,7 @@ module   RdrHsSyn (
         checkContext,         -- HsType -> P HsContext
         checkPattern,         -- HsExp -> P HsPat
         bang_RDR,
+        isBangRdr,
         checkPatterns,        -- SrcLoc -> [HsExp] -> P [HsPat]
         checkMonadComp,       -- P (HsStmtContext RdrName)
         checkCommand,         -- LHsExpr RdrName -> P (LHsCmd RdrName)
@@ -1162,6 +1163,10 @@ plus_RDR = mkUnqual varName (fsLit "+") -- Hack
 bang_RDR = mkUnqual varName (fsLit "!") -- Hack
 pun_RDR  = mkUnqual varName (fsLit "pun-right-hand-side")
 
+isBangRdr :: RdrName -> Bool
+isBangRdr (Unqual occ) = occNameFS occ == fsLit "!"
+isBangRdr _ = False
+
 checkPatField :: SDoc -> LHsRecField GhcPs (LHsExpr GhcPs)
               -> P (LHsRecField GhcPs (LPat GhcPs))
 checkPatField msg (dL->L l fld) = do p <- checkLPat msg (hsRecFieldArg fld)
diff --git a/testsuite/tests/parser/should_compile/T16339.hs b/testsuite/tests/parser/should_compile/T16339.hs
new file mode 100644
index 0000000000..9bb8349ad4
--- /dev/null
+++ b/testsuite/tests/parser/should_compile/T16339.hs
@@ -0,0 +1,18 @@
+{-# LANGUAGE ExplicitNamespaces, TypeOperators, RoleAnnotations #-}
+{-# OPTIONS -Wno-duplicate-exports #-}
+
+module T16339
+  (
+    type (!),
+    type (!)(Bang),
+    type (!)(..),
+    type (.),
+    type (.)(Dot),
+    type (.)(..),
+  ) where
+
+data a ! b = Bang
+data f . g = Dot
+
+type role (!) phantom phantom
+type role (.) phantom phantom
diff --git a/testsuite/tests/parser/should_compile/all.T b/testsuite/tests/parser/should_compile/all.T
index b3f693d783..1c5c225d65 100644
--- a/testsuite/tests/parser/should_compile/all.T
+++ b/testsuite/tests/parser/should_compile/all.T
@@ -141,3 +141,4 @@ test('T15279', normalise_errmsg_fun(only_MG_loc), compile, [''])
 test('T15457', normal, compile, [''])
 test('T15675', normal, compile, [''])
 test('T15781', normal, compile, [''])
+test('T16339', normal, compile, [''])