[MERGE] Don't ask a password if there is no real terminal. (#69851)

[James Westby]

On Wed, 2008-03-12 at 00:23 +0200, Alexander Belchenko wrote:
> This patch try to partially address of problem of using native bzr.exe on Cygwin.
> Often it's used with non-standard terminals, and when operation with sftp or bzr+ssh
> transport is invoked it seems like bzr.exe hang. Actually it's not hang, but try
> to ask a password. And because in this case there is no real windows stdin, bzr
> will wait infinitely without any sign.
> 
> I'm also able to reproduce this behavior when I run bzr from inside FTE editor
> as subprocess. In this case I'm also able to get the same pseudo-hang.
> 
> Explicit check for sys.stdin.isatty() prevents of routing bzr to dead-end.

Hi Alexander,

The change seems pretty sensible to me.

My instinct is to ask for a test. Could one be made by temporarily
redirecting stdin from a tempfile?

I don't really know what a test for this should be, and I realise
that somethings could have the potential to cause havoc with the rest
of the test suite.

Thanks,

James