Comment on the cause for 'group executable' == no

tests/test_which.py

@@ -188,6 +188,10 @@ def test_which_should_match_other_group_user(self):
             shutil.copy(bin_echo, bin_path)
             isroot = os.getuid() == 0
             for should_match, mode in (
+                # note that although the file may have matching 'group' or
+                # 'other' executable permissions, it is *not* executable
+                # because the current uid is the owner of the file -- which
+                # takes precedence
                 (False,  0o000),   # ----------, no
                 (isroot, 0o001),   # ---------x, no
                 (isroot, 0o010),   # ------x---, no

tools/teamcity-runtests.sh

@@ -29,7 +29,7 @@ workon ${venv} || mkvirtualenv -p `which python${pyversion}` ${venv} || true
 
 # install ptyprocess
 cd $here/../../ptyprocess
-pip uninstall ptyprocess || true
+pip uninstall --yes ptyprocess || true
 python setup.py install
 
 # install all test requirements