testsuite: Add test for #18101wip/T18101

4 files changed, 27 insertions, 0 deletions

diff --git a/testsuite/tests/generics/T18101/T18101.hs b/testsuite/tests/generics/T18101/T18101.hs
new file mode 100644
index 0000000000..0cecb2579a
--- /dev/null
+++ b/testsuite/tests/generics/T18101/T18101.hs
@@ -0,0 +1,5 @@
+module T18101 where
+
+infixr 5 :*
+
+data List a = a :* List a
diff --git a/testsuite/tests/generics/T18101/T18101.script b/testsuite/tests/generics/T18101/T18101.script
new file mode 100644
index 0000000000..c9c08c96f1
--- /dev/null
+++ b/testsuite/tests/generics/T18101/T18101.script
@@ -0,0 +1,5 @@
+:load T18101
+:set -XStandaloneDeriving -XDeriveGeneric -XFlexibleInstances
+import GHC.Generics
+deriving instance Generic (List Int)
+:kind! (Rep (List Int))
diff --git a/testsuite/tests/generics/T18101/T18101.stdout b/testsuite/tests/generics/T18101/T18101.stdout
new file mode 100644
index 0000000000..7ef1dc21f8
--- /dev/null
+++ b/testsuite/tests/generics/T18101/T18101.stdout
@@ -0,0 +1,13 @@
+(Rep (List Int)) :: * -> *
+= D1
+    ('MetaData "List" "T18101" "main" 'False)
+    (C1
+       ('MetaCons ":*" ('InfixI 'RightAssociative 5) 'False)
+       (S1
+          ('MetaSel
+             'Nothing 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy)
+          (Rec0 Int)
+        :*: S1
+              ('MetaSel
+                 'Nothing 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy)
+              (Rec0 (List Int))))
diff --git a/testsuite/tests/generics/T18101/all.T b/testsuite/tests/generics/T18101/all.T
new file mode 100644
index 0000000000..f69baf8f2d
--- /dev/null
+++ b/testsuite/tests/generics/T18101/all.T
@@ -0,0 +1,4 @@
+# This test verifies that fixity is correctly reflected in Generic instances
+# derived for types living outside the current module.
+
+test('T18101', expect_broken(18101), ghci_script, ['T18101.script'])