help: clarify behavior of server.concurrent-push-mode So it doesn't seemingly say that old clients cannot talk to server configured with concurrent-push-mode=check-related. They can, they just don't get the benefit. Differential Revision: https://phab.mercurial-scm.org/D8201

commit: error out on unresolved files even if commit would be empty Differential Revision: https://phab.mercurial-scm.org/D8195

tests: add test of committing with conflicts but no changes in wdir I'm about to change the behavior slightly here, so let's have a test that shows that. Differential Revision: https://phab.mercurial-scm.org/D8194

transaction: clarify the logic around pre-finalize/post-finalize I am taking a bit more verbose route, but I find it easier to follow for people who (re)discover the code. (This is a gratuitous cleanup I did while looking at something else.) Differential Revision: https://phab.mercurial-scm.org/D8176

transaction: move constant to upper case These constant are internal to the module and can be safely renamed. Having them upper case help to clarify their "constant" status. (This is a gratuitous cleanup I did while looking at something else.) Differential Revision: https://phab.mercurial-scm.org/D8175

tests: handle In-Reply-To headers for line wrapping Python 3 tends to insert a newline for both Message-ID and In-Reply-To headers, so unwrap both. Just check the wrapped line format explicitly without regular expression. Differential Revision: https://phab.mercurial-scm.org/D8171