Environment to run tests in, changing file permissions on Cygwin

[Matt Mackall]

On Thu, 2016-01-28 at 15:18 +0100, Dr Rainer Woitok wrote:
> Greetings,
> 
> after recently updating my local clone  of the Mercurial source reposit-
> ory to 3.7-rc+epsilon  I ran "make tests" just for the fun of it ... and
> received plenty of output.

Support for running the test suite on Unix-deficient operating systems is best-
effort.

> $ unset CDPATH PS4

Noted. We should probably switch to a whitelist.

> --- /home/Rainer/repo/mercurial/tests/test-revert.t
> +++ /home/Rainer/repo/mercurial/tests/test-revert.t.err
> @@ -169,20 +169,19 @@
>  #if execbit
>    $ chmod +x c
>    $ hg revert --all
> -  reverting c

If this test is being run on Windows, it means our test for exec bit support is
being fooled:

https://www.selenic.com/hg/file/tip/tests/hghave.py#l138

What does "hg debugfs" say?

> Maybe that's a general Cygwin problem, as Cygwin's stock Mercurial pack-
> age features the same behaviour, as can be seen in:

I'm pretty sure this used to work, but it wouldn't surprise me if Cygwin has
become more devious.

-- 
Mathematics is the supreme nostalgia of our time.