Merge pull request pypa#9375 from jdufresne/dict-set-comprehension

Use dict and set comprehension where available

Author: xavfernandez

news/24193261-eaf9-4117-a1a9-d5bb7f93b447.trivial.rst

@@ -129,10 +129,9 @@ def compress_for_rename(paths):
     This set may include directories when the original sequence of paths
     included every file on disk.
     """
-    case_map = dict((os.path.normcase(p), p) for p in paths)
+    case_map = {os.path.normcase(p): p for p in paths}
     remaining = set(case_map)
-    unchecked = sorted(set(os.path.split(p)[0]
-                           for p in case_map.values()), key=len)
+    unchecked = sorted({os.path.split(p)[0] for p in case_map.values()}, key=len)
     wildcards = set()  # type: Set[str]
 
     def norm_join(*a):

src/pip/_internal/req/req_uninstall.py

@@ -114,7 +114,7 @@ def wheel_dist_info_dir(source, name):
     it doesn't match the provided name.
     """
     # Zip file path separators must be /
-    subdirs = set(p.split("/", 1)[0] for p in source.namelist())
+    subdirs = {p.split("/", 1)[0] for p in source.namelist()}
 
     info_dirs = [s for s in subdirs if s.endswith('.dist-info')]