branchmap: use mmap for faster revbranchcache loading A typical revbranchmap usage is: - load the entire revbranchmap file into memory - maybe do a few lookups - add a few bytes to it - write the addition to disk There's no reason to load the entire revbranchmap into memory. We can split it into a large immutable prefix and a mutable suffix, and then memorymap the prefix, thus saving all the useless loading. Benchmarking on some real-world pushes suggests that out of ~100s server-side push handling revbranchcache handling is responsible for: * ~7s with no change * ~1.3s with the change, without mmap * 0.04s with the change, with mmap

hghave: add py312 and py313 While not required in the core test suite in the moment, these could be useful in the future or for extensions. For example, Python 3.12 removed distutils and it might make sense to differentiate based on that.

hghave: use strings instead of floats for version numbers passed to checkvers I think it’s a really bad idea to use floats for version numbers. One problem is that 3.10 is the same as 3.1.

py3: fully port doctest to py3

import-checker: make stdlib path detection work in virtual environments The previous logic tried to find the directory containing BaseHTTPServer, which didn’t work as indended because it was only present on Python 2. Instead, the argparse module is used now.

cleanup: remove unnecessary list constructor calls around list comprehensions

branching: merge stable into default

delta-find: pass the full deltainfo to the _DeltaSearch class Having more information is better, so we pass it directly.