test, tools: tools\test.py --help fails on Windows in shell with Unicode codepage #12786

J:\temp\_git\node-fork>tools\test.py --help
Traceback (most recent call last):
  File "J:\temp\_git\node-fork\tools\test.py", line 1769, in <module>
    sys.exit(Main())
  File "J:\temp\_git\node-fork\tools\test.py", line 1593, in Main
    (options, args) = parser.parse_args()
  File "C:\Python27\lib\optparse.py", line 1400, in parse_args
    stop = self._process_args(largs, rargs, values)
  File "C:\Python27\lib\optparse.py", line 1440, in _process_args
    self._process_long_opt(rargs, values)
  File "C:\Python27\lib\optparse.py", line 1515, in _process_long_opt
    option.process(opt, value, values, self)
  File "C:\Python27\lib\optparse.py", line 789, in process
    self.action, self.dest, opt, value, values, parser)
  File "C:\Python27\lib\optparse.py", line 811, in take_action
    parser.print_help()
  File "C:\Python27\lib\optparse.py", line 1670, in print_help
    file.write(self.format_help().encode(encoding, "replace"))
LookupError: unknown encoding: cp65001

J:\temp\_git\node-fork>chcp 1252
Active code page: 1252

J:\temp\_git\node-fork>tools\test.py --help
Usage: test.py [options]

Options:
  -h, --help            show this help message and exit
  -m MODE, --mode=MODE  The test modes in which to run (comma-separated)
  -v, --verbose         Verbose output
  --logfile=LOGFILE     write test output to file. NOTE: this only applies the
                        tap progress indicator
  -p PROGRESS, --progress=PROGRESS
                        The style of progress indicator (verbose, dots, color,
                        mono, tap)
  --report              Print a summary of the tests to be run
  -s SUITE, --suite=SUITE
                        A test suite
  -t TIMEOUT, --timeout=TIMEOUT
                        Timeout in seconds
  --arch=ARCH           The architecture to run tests for
  --snapshot            Run the tests with snapshot turned on
  --special-command=SPECIAL_COMMAND
  --node-args=NODE_ARGS
                        Args to pass through to Node
  --expect-fail         Expect test cases to fail
  --valgrind            Run tests through valgrind
  --check-deopts        Check tests for permanent deoptimizations
  --cat                 Print the source of the tests
  --flaky-tests=FLAKY_TESTS
                        Regard tests marked as flaky (run|skip|dontcare)
  --warn-unused         Report unused rules
  -j J                  The number of parallel tasks to run
  -J                    Run tasks in parallel on all cores
  --time                Print timing information after running
  --suppress-dialogs    Suppress Windows dialogs for crashing tests
  --no-suppress-dialogs
                        Display Windows dialogs for crashing tests
  --shell=SHELL         Path to V8 shell
  --store-unexpected-output
                        Store the temporary JS files from tests that fails
  --no-store-unexpected-output
                        Deletes the temporary JS files from tests that fails
  -r RUN, --run=RUN     Divide the tests in m groups (interleaved) and run
                        tests from group n (--run=n,m with n < m)
  --temp-dir=TEMP_DIR   Optional path to change directory used for tests
  --repeat=REPEAT       Number of times to repeat given tests
  --abort-on-timeout    Send SIGABRT instead of SIGTERM to kill processes that
                        time out