packaging: rename run_pyoxidizer() I'm going to split this function up in a future commit and I'll want the name "run_pyoxidizer()" for a lower-level function for invoking `pyoxidizer`. Differential Revision: https://phab.mercurial-scm.org/D10686

packaging: move documentation HTML building to own function This is part of some light refactoring to enable us to use PyOxidizer for WiX MSI installer generation. Differential Revision: https://phab.mercurial-scm.org/D10685

pyoxidizer: support code signing Newer versions of PyOxidizer feature built-in support for code signing. You simply declare a code signer in the Starlark configuration file, activate it for automatic signing, and PyOxidizer will add code signatures to signable files as it encounters them. This commit teaches our Starlark configuration file to enable automatic code signing. But only on Windows for the moment, as our immediate goal is to overhaul the Windows packaging. The feature is opt-in: you must pass variables to PyOxidizer's build context via `pyoxidizer build --var` or `pyoxidizer build --var-env` to activate code signing. Differential Revision: https://phab.mercurial-scm.org/D10684

pyoxidizer: support producing MSI installers Newer versions of PyOxidizer have support for building WiX MSI installers "natively." Essentially, you can script the definition of your WiX installer via Starlark and PyOxidizer can invoke WiX tools to produce the installer. This commit teaches our PyOxidizer config file to produce MSI installers similarly to how `contrib/packaging/packging.py wix` would do it. We had to make a very minor change to `mercurial.wxs` to reflect different paths depending on who builds. This is because when PyOxidizer builds WiX installers, it does so from an isolated directory, not Mercurial's source directory. We simply copy the files into the build environment so they are accessible. After this change, running `pyoxidizer build msi` produces a nearly identical install layout to what the previous method produces. When I applied this series on top of the 5.8 tag, here is the list of differences and explanations: * docs/*.html files are missing from the new installer because the Python build environment doesn't have docutils. * .pyd and .exe files differ, likely because I'm using a different Visual Studio toolchain on my local computer than the official build environment. * Various .dist-info/ directories have different names. This is because older versions of PyOxidizer had buggy behavior and weren't properly normalizing package names in .dist-info/ directories. e.g. we went from `cached-property-1.5.2.dist-info` to `cached_property-1.5.2.dist-info`. * Translations (.mo files) may be missing if gettext isn't in %Path%. This is because the packaging.py code installs gettext and ensures it can be found. * Some *.dist-info/RECORD files vary due to SHA-256 content digest divergence due to build environment differences. (This should be harmless.) * The new install layout ships a python3.dll because newer versions of PyOxidizer ship this file. * The new install layout has a different vcruntime140.dll and also a vcruntime140_1.dll because newer versions of PyOxidizer ship a newer version of the Visual C++ Redistributable Runtime. The new PyOxidizer functionality is not yet integrated with packaging.py. This will come in a subsequent commit. So for now, the new functionality introduced here is unused. Differential Revision: https://phab.mercurial-scm.org/D10683

pyoxidizer: use allocator_backend instead of raw_allocator The name of this attribute changed in PyOxidizer 0.11. Differential Revision: https://phab.mercurial-scm.org/D10682

pyoxidizer: simplify targets The split targets existed to enable the use of a non-default distribution flavor on Windows. Modern versions of PyOxidizer use the "standalone_dynamic" distribution flavor by default. So our split brain workaround is no longer needed. Here, we unify the targets. We also remove an unreferenced target function to create a resources file. Differential Revision: https://phab.mercurial-scm.org/D10681

contrib: install PyOxidizer 0.16.0 PyOxidizer now provides MSI installers and pre-built Linux binaries. So we install that way. This significantly reduces the time to bootstrap a new machine in automation, as building PyOxidizer from source on a low core count machine takes several minutes. This change temporarily breaks the ability of the automated environment to use the in-repo pyoxidizer.bzl configuration file, as there are backwards-incompatible changes with the upgrade that need to be reflected. We'll handle those in subsequent commits. Differential Revision: https://phab.mercurial-scm.org/D10680

pyoxidizer: pin Python to 3.8 Newer versions of PyOxidizer use version 3.9 by default. As part of upgrading PyOxidizer, we want to pin the version at 3.8 so we can compare differences more easily. Differential Revision: https://phab.mercurial-scm.org/D10679