From aaf47caf35984e614d93bd8bea5227df55e0e3e6 Mon Sep 17 00:00:00 2001
From: Chih-Hsuan Yen <yan12125@gmail.com>
Date: Mon, 27 May 2019 01:08:20 +0800
Subject: [PATCH] bpo-37053: handle strings like u"bar" correctly in
 Tools/parser/unparse.py (GH-13583)

Constant.kind is added in https://bugs.python.org/issue36280.
Current possible values for Constant.kind are "u" or None.

For r'bar' and b'bar', Constant.kind value is None, so there's no need
for special handling.


https://bugs.python.org/issue37053
---
 Lib/test/test_tools/test_unparse.py                          | 5 +++++
 .../Tools-Demos/2019-05-26-16-47-06.bpo-37053.-EYRuz.rst     | 1 +
 Tools/parser/unparse.py                                      | 2 ++
 3 files changed, 8 insertions(+)
 create mode 100644 Misc/NEWS.d/next/Tools-Demos/2019-05-26-16-47-06.bpo-37053.-EYRuz.rst

diff --git a/Lib/test/test_tools/test_unparse.py b/Lib/test/test_tools/test_unparse.py
index f3386f5e31a..a958ebb51cc 100644
--- a/Lib/test/test_tools/test_unparse.py
+++ b/Lib/test/test_tools/test_unparse.py
@@ -139,6 +139,11 @@ def test_fstrings(self):
         self.check_roundtrip(r"""f'{f"{0}"*3}'""")
         self.check_roundtrip(r"""f'{f"{y}"*3}'""")
 
+    def test_strings(self):
+        self.check_roundtrip("u'foo'")
+        self.check_roundtrip("r'foo'")
+        self.check_roundtrip("b'foo'")
+
     def test_del_statement(self):
         self.check_roundtrip("del x, y, z")
 
diff --git a/Misc/NEWS.d/next/Tools-Demos/2019-05-26-16-47-06.bpo-37053.-EYRuz.rst b/Misc/NEWS.d/next/Tools-Demos/2019-05-26-16-47-06.bpo-37053.-EYRuz.rst
new file mode 100644
index 00000000000..5320dc51f75
--- /dev/null
+++ b/Misc/NEWS.d/next/Tools-Demos/2019-05-26-16-47-06.bpo-37053.-EYRuz.rst
@@ -0,0 +1 @@
+Handle strings like u"bar" correctly in Tools/parser/unparse.py. Patch by Chih-Hsuan Yen.
\ No newline at end of file
diff --git a/Tools/parser/unparse.py b/Tools/parser/unparse.py
index 385902ef4bc..a5cc000676b 100644
--- a/Tools/parser/unparse.py
+++ b/Tools/parser/unparse.py
@@ -399,6 +399,8 @@ def _Constant(self, t):
         elif value is ...:
             self.write("...")
         else:
+            if t.kind == "u":
+                self.write("u")
             self._write_constant(t.value)
 
     def _List(self, t):