GH-116380: Speed up glob.glob() by removing some system calls

Doc/library/glob.rst

@@ -75,10 +75,6 @@ The :mod:`glob` module defines the following functions:
  Using the "``**``" pattern in large directory trees may consume
  an inordinate amount of time.
 
- .. note::
- This function may return duplicate path names if *pathname*
- contains multiple "``**``" patterns and *recursive* is true.
-
  .. versionchanged:: 3.5
  Support for recursive globs using "``**``".
 
@@ -88,6 +84,11 @@ The :mod:`glob` module defines the following functions:
  .. versionchanged:: 3.11
  Added the *include_hidden* parameter.
 
+ .. versionchanged:: 3.14
+ Matching path names are returned only once. In previous versions, this
+ function may return duplicate path names if *pathname* contains multiple
+ "``**``" patterns and *recursive* is true.
+
 
 .. function:: iglob(pathname, *, root_dir=None, dir_fd=None, recursive=False, \
  include_hidden=False)
@@ -98,10 +99,6 @@ The :mod:`glob` module defines the following functions:
  .. audit-event:: glob.glob pathname,recursive glob.iglob
  .. audit-event:: glob.glob/2 pathname,recursive,root_dir,dir_fd glob.iglob
 
- .. note::
- This function may return duplicate path names if *pathname*
- contains multiple "``**``" patterns and *recursive* is true.
-
  .. versionchanged:: 3.5
  Support for recursive globs using "``**``".
 
@@ -111,6 +108,11 @@ The :mod:`glob` module defines the following functions:
  .. versionchanged:: 3.11
  Added the *include_hidden* parameter.
 
+ .. versionchanged:: 3.14
+ Matching path names are yielded only once. In previous versions, this
+ function may yield duplicate path names if *pathname* contains multiple
+ "``**``" patterns and *recursive* is true.
+
 
 .. function:: escape(pathname)
 

Doc/whatsnew/3.14.rst

@@ -968,6 +968,14 @@ base64
  (Contributed by Bénédikt Tran, Chris Markiewicz, and Adam Turner in :gh:`118761`.)
 
 
+glob
+----
+
+* Reduce the number of system calls in :func:`glob.glob` and :func:`~glob.iglob`,
+ thereby improving the speed of globbing operations by 20-80%.
+ (Contributed by Barney Gale in :gh:`116380`.)
+
+
 io
 ---
 * :mod:`io` which provides the built-in :func:`open` makes less system calls