[commit: ghc] master: Typeable: Only render saturated tuple types with tuple syntax (846fe90)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/846fe90464a1916df4ea72659255963a596eec84/ghc

>---------------------------------------------------------------

commit 846fe90464a1916df4ea72659255963a596eec84
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Mon Oct 15 13:36:16 2018 -0400

    Typeable: Only render saturated tuple types with tuple syntax
    
    This isn't as efficient as it could be since it needs to compute the
    kind of the type. However, this is `show` so there shouldn't be any
    particular expectation of speed.
    
    Fixes #14341.
    
    Test Plan: Validate
    
    Reviewers: hvr
    
    Subscribers: monoidal, rwbarton, carter
    
    GHC Trac Issues: #14341
    
    Differential Revision: https://phabricator.haskell.org/D5080


>---------------------------------------------------------------

846fe90464a1916df4ea72659255963a596eec84
 libraries/base/Data/Typeable/Internal.hs           | 6 +++++-
 testsuite/tests/typecheck/should_run/T14341.hs     | 9 +++++++++
 testsuite/tests/typecheck/should_run/T14341.stdout | 3 +++
 testsuite/tests/typecheck/should_run/all.T         | 1 +
 4 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/libraries/base/Data/Typeable/Internal.hs b/libraries/base/Data/Typeable/Internal.hs
index 0d4fc82..06d225a 100644
--- a/libraries/base/Data/Typeable/Internal.hs
+++ b/libraries/base/Data/Typeable/Internal.hs
@@ -773,7 +773,11 @@ showTypeable _ TrType = showChar '*'
 showTypeable _ rep
   | isListTyCon tc, [ty] <- tys =
     showChar '[' . shows ty . showChar ']'
-  | isTupleTyCon tc =
+
+    -- Take care only to render saturated tuple tycon applications
+    -- with tuple notation (#14341).
+  | isTupleTyCon tc,
+    Just _ <- TrType `eqTypeRep` typeRepKind rep =
     showChar '(' . showArgs (showChar ',') tys . showChar ')'
   where (tc, tys) = splitApps rep
 showTypeable _ (TrTyCon {trTyCon = tycon, trKindVars = []})
diff --git a/testsuite/tests/typecheck/should_run/T14341.hs b/testsuite/tests/typecheck/should_run/T14341.hs
new file mode 100644
index 0000000..72d2f63
--- /dev/null
+++ b/testsuite/tests/typecheck/should_run/T14341.hs
@@ -0,0 +1,9 @@
+{-# LANGUAGE TypeApplications #-}
+
+import Type.Reflection
+
+main :: IO ()
+main = do
+    print $ typeRep @((,,))
+    print $ typeRep @((,,) Int)
+    print $ typeRep @((,,) Int Int Int)
diff --git a/testsuite/tests/typecheck/should_run/T14341.stdout b/testsuite/tests/typecheck/should_run/T14341.stdout
new file mode 100644
index 0000000..ea3d344
--- /dev/null
+++ b/testsuite/tests/typecheck/should_run/T14341.stdout
@@ -0,0 +1,3 @@
+(,,)
+(,,) Int
+(Int,Int,Int)
\ No newline at end of file
diff --git a/testsuite/tests/typecheck/should_run/all.T b/testsuite/tests/typecheck/should_run/all.T
index a96c2b7..4f75c70 100755
--- a/testsuite/tests/typecheck/should_run/all.T
+++ b/testsuite/tests/typecheck/should_run/all.T
@@ -136,3 +136,4 @@ test('T13838', [exit_code(1), omit_ways(['ghci'])], compile_and_run, ['-fdefer-t
 test('T14218', normal, compile_and_run, [''])
 test('T14236', normal, compile_and_run, [''])
 test('T14925', normal, compile_and_run, [''])
+test('T14341', normal, compile_and_run, [''])