pathutil: use `finddirs_rev_noroot` instead of `parts` The benefit this brings is very tiny, if it's even there, since we still didn't get rid of the [parts] computation. It probably won't be worth it without the subsequent patch that adds one more use of [finddirs_rev_noroot]

pathutil: add the more efficient finddir iterator (to be used in subsequent commits)

typing: import unconditionally This is needed if we're writing python3 signatures.

tests: check how hgweb handles HEAD requests This test file is loosely based on test-hgweb.t. HEAD support originally implemented in fda5a4b853ab.

tests: test hg status --all with hgext/git There's a TODO item in git/dirstate.py about obtaining clean files in a more straightforward way, let's first test that status can and does show clean files at all.

tests: aborting on unknown revision emits exit code 10 even with hgext/git

worker: avoid reading 1 byte at a time from the OS pipe Apparently `pickle.load` does a lot of small reads, many of them literally 1-byte, so it benefits greatly from buffering. This change enables the buffering, at the cost of more complicated interaction with the `selector` API. On one repository with ~400k files this reduces the time by about ~30s, from ~60 to ~30s. The difference is so large because the actual updating work is parallellized, while these small reads are bottlenecking the central hg process.

diffutil: rewrite an ersatz ternary operator for building diffopts.text Pytype tends to get confused by these, but the real problem here is that if the caller passes `opts={}` as TortoiseHg has been doing, that is set as the value for `diffopts.text` when in reality it expects a boolean. When `None` is passed explicitly, the default value in `mdiff.defaultopts` is assigned.

mdiff: add a __str__ method to diffopts This makes it easier to debug by just formatting the object into `%s` to see the members and state, instead of the class and memory address.

debugshell: allow TortoiseHg builds to exit with the usual `quit()` command I've long been annoyed that `quit()` only randomly worked to exit the interpreter. When that happens, Ctrl+C doesn't work either (it simply prints "KeyboardInterrupt"), so then you have to `import sys` and `sys.exit()`. But it turns out that the behavior isn't random and it depended on which `hg.exe` was picked up on PATH first, because py2exe disables site initialization. I wasn't able to persuade the maintainer to allow an opt-in to initialization[1], but this works around it so that the behavior is now consistent however `hg.exe` is built. TortoiseHg 6.3.3 will be the first build that includes the site package, so handle the ImportError. [1] https://github.com/py2exe/py2exe/issues/154