wrapper: switch to functools.lru_cache

No need to implement our own caching logic with newer Python.

Change-Id: Idc3243b8e22ff020817b0a4f18c9b86b1222d631
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/354357
Tested-by: Mike Frysinger <vapier@google.com>
Reviewed-by: Josip Sokcevic <sokcevic@google.com>

2 files changed, 9 insertions, 12 deletions

diff --git a/tests/test_wrapper.py b/tests/test_wrapper.py
index 2a0e542b..ef879a5d 100644
--- a/tests/test_wrapper.py
+++ b/tests/test_wrapper.py
@@ -38,7 +38,7 @@ class RepoWrapperTestCase(unittest.TestCase):
 
   def setUp(self):
     """Load the wrapper module every time."""
-    wrapper._wrapper_module = None
+    wrapper.Wrapper.cache_clear()
     self.wrapper = wrapper.Wrapper()
 
 
diff --git a/wrapper.py b/wrapper.py
index 65dcf3c6..3099ad5d 100644
--- a/wrapper.py
+++ b/wrapper.py
@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import functools
 import importlib.machinery
 import importlib.util
 import os
@@ -21,15 +22,11 @@ def WrapperPath():
   return os.path.join(os.path.dirname(__file__), 'repo')
 
 
-_wrapper_module = None
-
-
+@functools.lru_cache(maxsize=None)
 def Wrapper():
-  global _wrapper_module
-  if not _wrapper_module:
-    modname = 'wrapper'
-    loader = importlib.machinery.SourceFileLoader(modname, WrapperPath())
-    spec = importlib.util.spec_from_loader(modname, loader)
-    _wrapper_module = importlib.util.module_from_spec(spec)
-    loader.exec_module(_wrapper_module)
-  return _wrapper_module
+  modname = 'wrapper'
+  loader = importlib.machinery.SourceFileLoader(modname, WrapperPath())
+  spec = importlib.util.spec_from_loader(modname, loader)
+  module = importlib.util.module_from_spec(spec)
+  loader.exec_module(module)
+  return module