windows: introduce a `util.abspath` to replace os.path.abspath This will let us mitigate the drive letter capitalization hell. See inline comment for details. Differential Revision: https://phab.mercurial-scm.org/D11059

windows: enforce upper case drive letter for getcwd in mercurial too This is affecting code that checks if a pull/push destination is the same as a configured one. For example the one creating divergent bookmark. Doing this fixes will help fixing `test-bookmarks.t` and `test-bookflow.t` on Windows. However, we also need to fix `abspath` invocation. Differential Revision: https://phab.mercurial-scm.org/D11058

hg-ssh: normalize the drive of the current working directory on windows For some reason os.getcwd() can return either `c:` or `C:`. We normalize this to `C:` and the like. This fix `test-ssh-bundle1.t` on windows. Differential Revision: https://phab.mercurial-scm.org/D11042

run-tests: enforce the drive letter from `getcwd` to upper case For some reason os.getcwd() can return either `c:` or `C:` depending of which binary you used on Windows. We normalize this to `C:` and the like. This fix `test-run-tests.t` on windows as the drive letter in "$TESTTMP" was "wrongly" set to 'c:/' if the test path wasn't explicitly specified. Differential Revision: https://phab.mercurial-scm.org/D11035

sigpipe-remote: simply delegate pipe forwarding to subprocess we can kill Instead of using sophisticated logics with thread a non blocking pipes, we simply spawn two new process in charge of reading the pipe and sending the result to the client. When it is time to cut the pipe we violently kill them without any remorse. This close the pipe regardless of any in progress `os.read` call. Ironically this is the very same things as what the initial shell setup was doing, but in Python. This makes the test pass run properly on Windows. This also reveal that the Windows behavior is broken as the transaction is not properly rollback. However this is an adventure for another time. Making the test behave properly was enough effort. Differential Revision: https://phab.mercurial-scm.org/D11087

sigpipe-remote: verify the script is IO are unbuffered We don't want to get stuck anywhere by buffers. Differential Revision: https://phab.mercurial-scm.org/D11086