nodemap: add a test about racy commit during stream clone That test show that the resulting client nodemap is different from the server one. This happens because the server one transferred a corrupted node map. The data file match the pre-commit content while the docket has post commit content. As the result the nodemap was detected invalid and recomputed. When running without the rust implementation, the code is also generating a new datafile unconditionally, This mean the older file is no longer there are transfer time, resulting in a crash. We will fix this issue later, but we start with writing tests highlighting the issue. Differential Revision: https://phab.mercurial-scm.org/D10479

streamclone: remove sleep based "synchronisation" in tests Sleep based test synchronisation does not work. Variation in machine performance and load can make the two process miss their windows. Instead we migrate to explicit signaling through the file system as other tests file are using. Differential Revision: https://phab.mercurial-scm.org/D10478

testing: add a `write_file` function The function is kinda trivial, but having a simple function avoid silly mistake. Differential Revision: https://phab.mercurial-scm.org/D10477

testing: add a utility function to wait for file create This is similar to `tests/testlib/wait-on-file`, but for the python code Differential Revision: https://phab.mercurial-scm.org/D10476

streamclone: check the errors log in tests Code can be buggy, in that case having error message tend to help. Differential Revision: https://phab.mercurial-scm.org/D10475

mail: use a context manager when writing to mbox Differential Revision: https://phab.mercurial-scm.org/D10484

errors: remove unnecessary varargs handling from OutOfBandError In my recent D10465, I moved some code over from scmutil into `OutOfBandError.__init__`. The code was written to deal with an arbitrary number of `message` arguments to the constructor. It turns out that we only ever pass 0 or 1. Given that, let's simplify it. Differential Revision: https://phab.mercurial-scm.org/D10483

phab-refresh: use a special comment on the stable branch Phabricator make it hard to spot the branch information. As a result patch intended for stable are consistently queued for default. We add a special command and flashy GIF to try to attract reviewer attention on the fact patch are intended for stable. Differential Revision: https://phab.mercurial-scm.org/D10464

phab-refresh: extract the comment in a variable This make the script more readable and it is about to become more complex. Differential Revision: https://phab.mercurial-scm.org/D10463

tests: make test-archive.t pass on py3.9 (issue6504) Something got stricter at parsing URL query parameters and now the parameters need to be separated by "&"; ";" is no longer allowed. See issue6504 for details. Differential Revision: https://phab.mercurial-scm.org/D10472