[commit: ghc] ghc-8.0: More tests for Trac #12522 (801cbb4)

[git at git.haskell.org]

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

On branch  : ghc-8.0
Link       : http://ghc.haskell.org/trac/ghc/changeset/801cbb42638714004587ba39d1d6b2bbc9ad3b9d/ghc

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

commit 801cbb42638714004587ba39d1d6b2bbc9ad3b9d
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Mon Oct 10 13:57:01 2016 +0100

    More tests for Trac #12522
    
    These ones test the variations in coment:15 of the ticket
    
    (cherry picked from commit a6111b8cc14a5dc019e2613f6f634dec4eb57a8a)


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

801cbb42638714004587ba39d1d6b2bbc9ad3b9d
 .../tests/indexed-types/should_compile/T12522b.hs   | 20 ++++++++++++++++++++
 testsuite/tests/indexed-types/should_compile/all.T  |  1 +
 .../tests/indexed-types/should_fail/T12522a.hs      | 21 +++++++++++++++++++++
 .../should_fail/T12522a.stderr}                     | 18 +++++++-----------
 testsuite/tests/indexed-types/should_fail/all.T     |  1 +
 5 files changed, 50 insertions(+), 11 deletions(-)

diff --git a/testsuite/tests/indexed-types/should_compile/T12522b.hs b/testsuite/tests/indexed-types/should_compile/T12522b.hs
new file mode 100644
index 0000000..7501382
--- /dev/null
+++ b/testsuite/tests/indexed-types/should_compile/T12522b.hs
@@ -0,0 +1,20 @@
+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE KindSignatures #-}
+{-# LANGUAGE TypeFamilyDependencies #-}
+{-# LANGUAGE TypeOperators #-}
+
+module T12522a where
+
+newtype I a = I a
+
+type family Curry (as :: [*]) b = f | f -> as b where
+    Curry '[] b = I b
+    Curry (a:as) b = a -> Curry as b
+
+data Uncurried (as :: [*]) b
+
+def :: Curry as b -> Uncurried as b
+def = undefined
+
+-- test2 :: Uncurried [Bool, Bool] Bool
+test2 = def $ \a b -> I $ a && b
diff --git a/testsuite/tests/indexed-types/should_compile/all.T b/testsuite/tests/indexed-types/should_compile/all.T
index 9763d89..ab49be4 100644
--- a/testsuite/tests/indexed-types/should_compile/all.T
+++ b/testsuite/tests/indexed-types/should_compile/all.T
@@ -275,3 +275,4 @@ test('T11361', normal, compile, [''])
 test('T11361a', normal, compile_fail, [''])
 test('T12175', normal, compile, [''])
 test('T12522', normal, compile, [''])
+test('T12522b', normal, compile, [''])
diff --git a/testsuite/tests/indexed-types/should_fail/T12522a.hs b/testsuite/tests/indexed-types/should_fail/T12522a.hs
new file mode 100644
index 0000000..eb855f4
--- /dev/null
+++ b/testsuite/tests/indexed-types/should_fail/T12522a.hs
@@ -0,0 +1,21 @@
+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE KindSignatures #-}
+{-# LANGUAGE TypeFamilyDependencies #-}
+{-# LANGUAGE TypeOperators #-}
+
+module T12522a where
+
+newtype I a = I a
+
+type family Curry (as :: [*]) b = f | f -> as b where
+    Curry '[] b = I b
+    Curry (a:as) b = a -> Curry as b
+
+data Uncurried (as :: [*]) b
+
+def :: Curry as b -> Uncurried as b
+def = undefined
+
+-- test :: Uncurried [Int, String] String
+test = def $ \n s -> I $ show n ++ s
+
diff --git a/testsuite/tests/typecheck/should_compile/holes2.stderr b/testsuite/tests/indexed-types/should_fail/T12522a.stderr
similarity index 54%
copy from testsuite/tests/typecheck/should_compile/holes2.stderr
copy to testsuite/tests/indexed-types/should_fail/T12522a.stderr
index eb8d56f..7356791 100644
--- a/testsuite/tests/typecheck/should_compile/holes2.stderr
+++ b/testsuite/tests/indexed-types/should_fail/T12522a.stderr
@@ -1,7 +1,10 @@
 
-holes2.hs:3:5: warning: [-Wdeferred-type-errors (in -Wdefault)]
+T12522a.hs:20:26: error:
     • Ambiguous type variable ‘a0’ arising from a use of ‘show’
       prevents the constraint ‘(Show a0)’ from being solved.
+      Relevant bindings include
+        n :: a0 (bound at T12522a.hs:20:15)
+        test :: Uncurried '[a0, [Char]] [Char] (bound at T12522a.hs:20:1)
       Probable fix: use a type annotation to specify what ‘a0’ should be.
       These potential instances exist:
         instance Show Ordering -- Defined in ‘GHC.Show’
@@ -10,13 +13,6 @@ holes2.hs:3:5: warning: [-Wdeferred-type-errors (in -Wdefault)]
         ...plus 22 others
         ...plus five instances involving out-of-scope types
         (use -fprint-potential-instances to see them all)
-    • In the expression: show _
-      In an equation for ‘f’: f = show _
-
-holes2.hs:3:10: warning: [-Wtyped-holes (in -Wdefault)]
-    • Found hole: _ :: a0
-      Where: ‘a0’ is an ambiguous type variable
-    • In the first argument of ‘show’, namely ‘_’
-      In the expression: show _
-      In an equation for ‘f’: f = show _
-    • Relevant bindings include f :: String (bound at holes2.hs:3:1)
+    • In the first argument of ‘(++)’, namely ‘show n’
+      In the second argument of ‘($)’, namely ‘show n ++ s’
+      In the expression: I $ show n ++ s
diff --git a/testsuite/tests/indexed-types/should_fail/all.T b/testsuite/tests/indexed-types/should_fail/all.T
index 83dd708..7c55bde 100644
--- a/testsuite/tests/indexed-types/should_fail/all.T
+++ b/testsuite/tests/indexed-types/should_fail/all.T
@@ -140,3 +140,4 @@ test('T10899', normal, compile_fail, [''])
 test('T11136', normal, compile_fail, [''])
 test('T7788', normal, compile_fail, [''])
 test('T12041', normal, compile_fail, [''])
+test('T12522a', normal, compile_fail, [''])