bpo-33251: Prevent ConfigParser.items returning items present in vars. (#6446)

* bpo-33251: ConfigParser.items no longer returns items present in vars.

Documentation for `ConfigParser.items()` states:
'Items present in vars no longer appear in the result.'

This fix aligns behaviour to that specified in the documentation.

1 files changed, 2 insertions, 1 deletions

diff --git a/Lib/configparser.py b/Lib/configparser.py
index 33dc9b9046..a681d3990e 100644
--- a/Lib/configparser.py
+++ b/Lib/configparser.py
@@ -846,6 +846,7 @@ class RawConfigParser(MutableMapping):
         except KeyError:
             if section != self.default_section:
                 raise NoSectionError(section)
+        orig_keys = list(d.keys())
         # Update with the entry specific variables
         if vars:
             for key, value in vars.items():
@@ -854,7 +855,7 @@ class RawConfigParser(MutableMapping):
             section, option, d[option], d)
         if raw:
             value_getter = lambda option: d[option]
-        return [(option, value_getter(option)) for option in d.keys()]
+        return [(option, value_getter(option)) for option in orig_keys]
 
     def popitem(self):
         """Remove a section from the parser and return it as