utils: T9185: revert the proposed fix ask_yes_no() busy-looping forever on non-tty stdin

2 files changed, 2 insertions, 70 deletions

diff --git a/python/vyos/utils/io.py b/python/vyos/utils/io.py
index 58ceb3476..77e30cbb0 100644
--- a/python/vyos/utils/io.py
+++ b/python/vyos/utils/io.py
@@ -55,25 +55,8 @@ def ask_input(question, default='', numeric_only=False, valid_responses=[],
     return response
 
 def ask_yes_no(question, default=False) -> bool:
-    """Ask a yes/no question via input() and return their answer.
-
-    Raises EOFError immediately if stdin is not a TTY (e.g. non-interactive
-    scripts), instead of ever calling input(). A silent default here has
-    caused real incidents (T9185): a caller that forgets to guard an
-    interactive-only prompt gets no error and no visible hang, just a
-    process quietly pegging a core. Callers that are meant to run
-    non-interactively must check for that explicitly (see the no_prompt
-    parameter used across config_mgmt.py/backend.py) rather than rely on
-    this function to fall back to a default.
-    """
-    from sys import stdin, stdout
-
-    if not stdin.isatty():
-        raise EOFError(
-            f'Cannot prompt "{question}" ([Y/n] default={default}): '
-            'stdin is not a TTY. Pass an explicit non-interactive option '
-            '(e.g. no_prompt/-y) instead of relying on ask_yes_no().'
-        )
+    """Ask a yes/no question via input() and return their answer."""
+    from sys import stdout
     default_msg = "[Y/n]" if default else "[y/N]"
     while True:
         try:
diff --git a/src/tests/test_utils_io.py b/src/tests/test_utils_io.py
deleted file mode 100644
index 9d6471e16..000000000
--- a/src/tests/test_utils_io.py
+++ /dev/null
@@ -1,51 +0,0 @@
-# Copyright VyOS maintainers and contributors <maintainers@vyos.io>
-#
-# This program is free software; you can redistribute it and/or modify
-# it under the terms of the GNU General Public License version 2 or later as
-# published by the Free Software Foundation.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
-import unittest
-from unittest.mock import patch
-
-from vyos.utils.io import ask_yes_no
-
-
-class TestVyOSUtilsIO(unittest.TestCase):
-    def test_ask_yes_no_non_interactive_raises_without_reading_stdin(self):
-        # T9185: on a non-TTY stdin (e.g. a non-interactive vbash session),
-        # input() raises EOFError immediately and forever; looping on it
-        # spins a core at 100% CPU. Returning a silent default instead is
-        # also wrong (jestabro/dmbaturin, PR #5390): a caller that forgot
-        # to guard this with an explicit non-interactive option would get
-        # no error and no visible hang, just a quietly-succeeding prompt.
-        # ask_yes_no() must raise immediately instead of ever calling
-        # input() or returning a default.
-        with patch('sys.stdin') as mock_stdin:
-            mock_stdin.isatty.return_value = False
-            with patch('builtins.input') as mock_input:
-                self.assertRaises(EOFError, ask_yes_no, 'Proceed?', default=True)
-                self.assertRaises(EOFError, ask_yes_no, 'Proceed?', default=False)
-                mock_input.assert_not_called()
-
-    def test_ask_yes_no_interactive_reads_input(self):
-        with patch('sys.stdin') as mock_stdin:
-            mock_stdin.isatty.return_value = True
-            with patch('builtins.input', return_value='y'):
-                self.assertTrue(ask_yes_no('Proceed?', default=False))
-            with patch('builtins.input', return_value='n'):
-                self.assertFalse(ask_yes_no('Proceed?', default=True))
-            with patch('builtins.input', return_value=''):
-                self.assertTrue(ask_yes_no('Proceed?', default=True))
-                self.assertFalse(ask_yes_no('Proceed?', default=False))
-
-
-if __name__ == '__main__':
-    unittest.main()