merge from 3.2

Lib/test/regrtest.py

@@ -33,7 +33,7 @@ Verbosity
 -W/--verbose3   -- display test output on failure
 -d/--debug      -- print traceback for failed tests
 -q/--quiet      -- no output unless one or more tests fail
--S/--slow       -- print the slowest 10 tests
+-o/--slow       -- print the slowest 10 tests
    --header     -- print header with interpreter info
 
 Selecting tests
@@ -340,7 +340,7 @@ def main(tests=None, testdir=None, verbose=0, quiet=False,
             start = a
         elif o in ('-s', '--single'):
             single = True
-        elif o in ('-S', '--slow'):
+        elif o in ('-o', '--slow'):
             print_slow = True
         elif o in ('-r', '--randomize'):
             randomize = True

Misc/NEWS

@@ -442,6 +442,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #13726: Fix the ambiguous -S flag in regrtest. It is -o/--slow for slow
+  tests.
+
 - Issue #12364: Fix a hang in concurrent.futures.ProcessPoolExecutor.
   The hang would occur when retrieving the result of a scheduled future after
   the executor had been shut down.