Move 'HsBangTy' out in constructor arguments

When run with -haddock, a constructor argument can have both a a
strictness/unpackedness annotation and a docstring. The parser binds
'HsBangTy' more tightly than 'HsDocTy', yet for constructor arguments we
really need the 'HsBangTy' on the outside.

This commit does this shuffling in the 'mkConDeclH98' and 'mkGadtDecl'
smart constructors.

Test Plan: haddockA038, haddockC038

Reviewers: bgamari, dfeuer

Reviewed By: bgamari

Subscribers: dfeuer, rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4727

5 files changed, 37 insertions, 0 deletions

diff --git a/testsuite/tests/haddock/should_compile_flag_haddock/all.T b/testsuite/tests/haddock/should_compile_flag_haddock/all.T
index 90d4a55c3f..5450fcbe7f 100644
--- a/testsuite/tests/haddock/should_compile_flag_haddock/all.T
+++ b/testsuite/tests/haddock/should_compile_flag_haddock/all.T
@@ -42,6 +42,7 @@ test('haddockA032', normal, compile, ['-haddock -ddump-parsed'])
 test('haddockA035', normal, compile, ['-haddock -ddump-parsed'])
 test('haddockA036', normal, compile, ['-haddock -ddump-parsed'])
 test('haddockA037', normal, compile, ['-haddock -ddump-parsed'])
+test('haddockA038', normal, compile, ['-haddock -ddump-parsed'])
 
 # The tests below this line are not duplicated in
 # should_compile_noflag_haddock.
diff --git a/testsuite/tests/haddock/should_compile_flag_haddock/haddockA038.hs b/testsuite/tests/haddock/should_compile_flag_haddock/haddockA038.hs
new file mode 100644
index 0000000000..b839bdee22
--- /dev/null
+++ b/testsuite/tests/haddock/should_compile_flag_haddock/haddockA038.hs
@@ -0,0 +1,14 @@
+module UnamedConstructorStrictFields where
+-- See #15206
+
+data A = A
+data B = B
+
+data Foo = MkFoo
+  {-# UNPACK #-} !A -- ^ Unpacked strict field
+                 B
+
+data Bar =
+  {-# UNPACK #-} !A -- ^ Unpacked strict field
+    :%%
+                 B
diff --git a/testsuite/tests/haddock/should_compile_flag_haddock/haddockA038.stderr b/testsuite/tests/haddock/should_compile_flag_haddock/haddockA038.stderr
new file mode 100644
index 0000000000..94318efe2b
--- /dev/null
+++ b/testsuite/tests/haddock/should_compile_flag_haddock/haddockA038.stderr
@@ -0,0 +1,7 @@
+
+==================== Parser ====================
+module UnamedConstructorStrictFields where
+data A = A
+data B = B
+data Foo = MkFoo {-# UNPACK #-} !A  Unpacked strict field B
+data Bar = {-# UNPACK #-} !A  Unpacked strict field :%% B
diff --git a/testsuite/tests/haddock/should_compile_noflag_haddock/all.T b/testsuite/tests/haddock/should_compile_noflag_haddock/all.T
index edb2bd0e05..4e52c2d92c 100644
--- a/testsuite/tests/haddock/should_compile_noflag_haddock/all.T
+++ b/testsuite/tests/haddock/should_compile_noflag_haddock/all.T
@@ -42,6 +42,7 @@ test('haddockC032', normal, compile, [''])
 test('haddockC035', normal, compile, [''])
 test('haddockC036', normal, compile, [''])
 test('haddockC037', normal, compile, [''])
+test('haddockC038', normal, compile, [''])
 
 # The tests below this line are not duplicated in
 # should_compile_flag_haddock.
diff --git a/testsuite/tests/haddock/should_compile_noflag_haddock/haddockC038.hs b/testsuite/tests/haddock/should_compile_noflag_haddock/haddockC038.hs
new file mode 100644
index 0000000000..b839bdee22
--- /dev/null
+++ b/testsuite/tests/haddock/should_compile_noflag_haddock/haddockC038.hs
@@ -0,0 +1,14 @@
+module UnamedConstructorStrictFields where
+-- See #15206
+
+data A = A
+data B = B
+
+data Foo = MkFoo
+  {-# UNPACK #-} !A -- ^ Unpacked strict field
+                 B
+
+data Bar =
+  {-# UNPACK #-} !A -- ^ Unpacked strict field
+    :%%
+                 B