run-tests.py: don't let hg run interactively in debug mode In normal test mode stdin is closed and hg is thus not interactive. In --debug mode stdin is inherited from the running console and to the tests, and hg could thus wait in prompts when running on Windows. See http://selenic.com/pipermail/mercurial-devel/2013-January/047548.html . Instead set ui.interactive=False to make Mercurial non-interactive. Other commands might still work differently in the --debug environment. This should solve the problem with hg waiting for input but still make it possible to add --debugger to hg in a test and run run-tests.py with --debug.