Install the backport of lru_cache and use it for overriden_method (the same behaviour before changing it to a function per stmt).

2 files changed, 6 insertions, 0 deletions

diff --git a/pylint/__pkginfo__.py b/pylint/__pkginfo__.py
index 1c14429e6..c2b60c688 100644
--- a/pylint/__pkginfo__.py
+++ b/pylint/__pkginfo__.py
@@ -25,6 +25,7 @@ if sys.platform == 'win32':
     install_requires.append('colorama')
 if sys.version_info[0] == 2:
     install_requires.append('configparser')
+    install_requires.append('backports.functools_lru_cache')
 
 
 license = 'GPL'
diff --git a/pylint/checkers/variables.py b/pylint/checkers/variables.py
index fef71b741..3290e886d 100644
--- a/pylint/checkers/variables.py
+++ b/pylint/checkers/variables.py
@@ -8,6 +8,10 @@ import os
 import sys
 import re
 from copy import copy
+try:
+    from functools import lru_cache
+except ImportError:
+    from backports.functools_lru_cache import lru_cache
 
 import six
 
@@ -48,6 +52,7 @@ def in_for_else_branch(parent, stmt):
     return (isinstance(parent, astroid.For) and
             any(else_stmt.parent_of(stmt) for else_stmt in parent.orelse))
 
+@lru_cache(maxsize=1000)
 def overridden_method(klass, name):
     """get overridden method if any"""
     try: