[Python-checkins] closes bpo-37675: Use pkgutil.iter_modules to find fixers in a package rather than listdir. (14942)

[Benjamin Peterson]

https://github.com/python/cpython/commit/93e8aa62cfd0a61efed4a61a2ffc2283ae986ef2
commit: 93e8aa62cfd0a61efed4a61a2ffc2283ae986ef2
branch: master
author: Benjamin Peterson <benjamin at python.org>
committer: GitHub <noreply at github.com>
date: 2019-07-24T16:38:50-07:00
summary:

closes bpo-37675: Use pkgutil.iter_modules to find fixers in a package rather than listdir. (14942)

files:
A Misc/NEWS.d/next/Tools-Demos/2019-07-24-16-20-54.bpo-37675.951Cvf.rst
M Lib/lib2to3/refactor.py

diff --git a/Lib/lib2to3/refactor.py b/Lib/lib2to3/refactor.py
index 7841b99a5cd4..55fd60fa27c3 100644
--- a/Lib/lib2to3/refactor.py
+++ b/Lib/lib2to3/refactor.py
@@ -14,6 +14,7 @@
 # Python imports
 import io
 import os
+import pkgutil
 import sys
 import logging
 import operator
@@ -30,13 +31,12 @@
 def get_all_fix_names(fixer_pkg, remove_prefix=True):
     """Return a sorted list of all available fix names in the given package."""
     pkg = __import__(fixer_pkg, [], [], ["*"])
-    fixer_dir = os.path.dirname(pkg.__file__)
     fix_names = []
-    for name in sorted(os.listdir(fixer_dir)):
-        if name.startswith("fix_") and name.endswith(".py"):
+    for finder, name, ispkg in pkgutil.iter_modules(pkg.__path__):
+        if name.startswith("fix_"):
             if remove_prefix:
                 name = name[4:]
-            fix_names.append(name[:-3])
+            fix_names.append(name)
     return fix_names
 
 
diff --git a/Misc/NEWS.d/next/Tools-Demos/2019-07-24-16-20-54.bpo-37675.951Cvf.rst b/Misc/NEWS.d/next/Tools-Demos/2019-07-24-16-20-54.bpo-37675.951Cvf.rst
new file mode 100644
index 000000000000..e28fa207f918
--- /dev/null
+++ b/Misc/NEWS.d/next/Tools-Demos/2019-07-24-16-20-54.bpo-37675.951Cvf.rst
@@ -0,0 +1 @@
+2to3 now works when run from a zipped standard library.