bpo-29637: clean docstring only if not None (GH-267)
diff --git a/Lib/ast.py b/Lib/ast.py
index 0729ee7..070c2be 100644
--- a/Lib/ast.py
+++ b/Lib/ast.py
@@ -194,11 +194,14 @@
Return the docstring for the given node or None if no docstring can
be found. If the node provided does not have docstrings a TypeError
will be raised.
+
+ If *clean* is `True`, all tabs are expanded to spaces and any whitespace
+ that can be uniformly removed from the second line onwards is removed.
"""
if not isinstance(node, (AsyncFunctionDef, FunctionDef, ClassDef, Module)):
raise TypeError("%r can't have docstrings" % node.__class__.__name__)
text = node.docstring
- if clean:
+ if clean and text:
import inspect
text = inspect.cleandoc(text)
return text
diff --git a/Lib/test/test_ast.py b/Lib/test/test_ast.py
index 366269f..2f59527 100644
--- a/Lib/test/test_ast.py
+++ b/Lib/test/test_ast.py
@@ -532,6 +532,7 @@
node = ast.parse('async def foo():\n """spam\n ham"""')
self.assertEqual(ast.get_docstring(node.body[0]), 'spam\nham')
+ self.assertIsNone(ast.get_docstring(ast.parse('')))
def test_literal_eval(self):
self.assertEqual(ast.literal_eval('[1, 2, 3]'), [1, 2, 3])