bpo-16355: Clarify when inspect.getcomments() returns None (#428) (#690)
Initial patch by Vajrasky Kok.
(cherry picked from commit 3f2155ffe683080f2a1b28408fa48d43ba92f943)
diff --git a/Doc/library/inspect.rst b/Doc/library/inspect.rst
index 3fa44a0..4ff2187 100644
--- a/Doc/library/inspect.rst
+++ b/Doc/library/inspect.rst
@@ -442,7 +442,9 @@
Return in a single string any lines of comments immediately preceding the
object's source code (for a class, function, or method), or at the top of the
- Python source file (if the object is a module).
+ Python source file (if the object is a module). If the object's source code
+ is unavailable, return ``None``. This could happen if the object has been
+ defined in C or the interactive shell.
.. function:: getfile(object)
diff --git a/Lib/test/test_inspect.py b/Lib/test/test_inspect.py
index 88eaabe..cfea281 100644
--- a/Lib/test/test_inspect.py
+++ b/Lib/test/test_inspect.py
@@ -387,6 +387,11 @@
def test_getcomments(self):
self.assertEqual(inspect.getcomments(mod), '# line 1\n')
self.assertEqual(inspect.getcomments(mod.StupidGit), '# line 20\n')
+ # If the object source file is not available, return None.
+ co = compile('x=1', '_non_existing_filename.py', 'exec')
+ self.assertIsNone(inspect.getcomments(co))
+ # If the object has been defined in C, return None.
+ self.assertIsNone(inspect.getcomments(list))
def test_getmodule(self):
# Check actual module