rust-update: make `update_from_null` respect `worker.numcpu` config option This was overlooked in the original series. This is important for tests (because we run many at once), and for the occasional end user that wants to keep their CPU usage in check. A future series should clean up this `worker` parameter tunelling business by rewriting the config in Rust, but doing so on stable would be a very bad idea.

rust-cpython: add a TODO about repo reuse This will need to be done soon-ish to prevent any surprises.

streamclone: disable the volatile file open handle optimization on Windows Leaving files open caused new failures like this, since a47f09da8bd1: diff --git a/tests/test-persistent-nodemap-stream-clone.t b/tests/test-persistent-nodemap-stream-clone.t --- a/tests/test-persistent-nodemap-stream-clone.t +++ b/tests/test-persistent-nodemap-stream-clone.t @@ -115,7 +115,12 @@ Do a mix of clone and commit at the same $ (hg clone -U --stream ssh://user@dummy/test-repo stream-clone-race-1 --debug 2>> clone-output | grep -E '00(changelog|manifest)' >> clone-output; touch $HG_TEST_STREAM_WALKED_FILE_3) & $ $RUNTESTDIR/testlib/wait-on-file 10 $HG_TEST_STREAM_WALKED_FILE_1 $ hg -R test-repo/ commit -m foo - created new head + transaction abort! + failed to recover 00changelog.n ([WinError 32] The process cannot access the file because it is being used by another process: b'$STR_REPR_TESTTMP\\test-repo/.hg/store/00changelog.n' -> b'$STR_REPR_TESTTMP\\test-repo/.hg/store/00changelog.n-f418dcd6') + rollback failed - please run hg recover + (failure reason: [WinError 32] The process cannot access the file because it is being used by another process: b'$STR_REPR_TESTTMP\\test-repo/.hg/store/00changelog.n' -> b'$STR_REPR_TESTTMP\\test-repo/.hg/store/00changelog.n-f418dcd6') + abort: The process cannot access the file because it is being used by another process: '$TESTTMP\test-repo\.hg\store\00changelog.n' + [255] $ touch $HG_TEST_STREAM_WALKED_FILE_2 $ $RUNTESTDIR/testlib/wait-on-file 10 $HG_TEST_STREAM_WALKED_FILE_3 $ cat clone-output Since the `VolatileManager` falls back to the old copy method when the open file threshold is exceeded, this just drops the threshold so that only 1 file is open. The actual value used (2) is unexpected, and explained inline. I'd like to have a config option for this so that we can test both ways (in theory, it could resort to copies on non-Windows systems too), but I don't see a `uimod.ui` handy. Alternately, I tried replacing the 3 `open()` calls in the `VolatileManager` with `util.posixfile()`, but that simply hung the test on Windows for some reason, I think on the same line that's indicated as failing above. (There was a `grep` command hanging around, as well as `hg -R test-repo serve --stdio`.)

tests: treat `select` as a built-in module on Windows This fixes: --- C:/Users/Matt/hg/tests/test-check-module-imports.t +++ C:/Users/Matt/hg/tests/test-check-module-imports.t.err @@ -43,3 +43,15 @@ > -X tests/test-verify-repo-operations.py \ > -X tests/test-extension.t \ > | sed 's-\\-/-g' | "$PYTHON" "$import_checker" - + hgext/zeroconf/Zeroconf.py:86: stdlib import "socket" follows local import: select\r (esc) + hgext/zeroconf/Zeroconf.py:87: stdlib import "struct" follows local import: select\r (esc) + hgext/zeroconf/Zeroconf.py:88: stdlib import "threading" follows local import: select\r (esc) + hgext/zeroconf/Zeroconf.py:89: stdlib import "time" follows local import: select\r (esc) + hgext/zeroconf/Zeroconf.py:90: stdlib import "traceback" follows local import: select\r (esc) + mercurial/posix.py:18: stdlib import "stat" follows local import: select\r (esc) + mercurial/posix.py:19: stdlib import "sys" follows local import: select\r (esc) + mercurial/posix.py:20: stdlib import "tempfile" follows local import: select\r (esc) + mercurial/posix.py:21: stdlib import "typing" follows local import: select\r (esc) + tests/tinyproxy.py:19: stdlib import "socket" follows local import: select\r (esc) + tests/tinyproxy.py:20: stdlib import "sys" follows local import: select\r (esc) + [1] ERROR: test-check-module-imports.t output changed

hgweb: skip logging ConnectionAbortedError Not stacktracing on `ConnectionResetError` was added in 6bbb12cba5a8 (though it was spelled differently for py2 support), but for some reason Windows occasionally triggers a `ConnectionAbortedError` here across various *.t files (notably `test-archive.t` and `test-lfs-serve-access.t`, but there are others). The payload that fails to send seems to be the html that describes the error to the client, so I suspect some code is seeing the error status code and closing the connection before the server gets to write this html. So don't log it, for test stability- nothing we can do anyway. FWIW, the CPython implementation of wsgihander specifically ignores these two errors, plus `BrokenPipeError`, with a comment that "we expect the client to close the connection abruptly from time to time"[1]. The `BrokenPipeError` is swallowed a level up in `do_write()`, and avoids writing the response following this stacktrace. I'm puzzled why a response is being written after these connection errors are detected- the CPython code referenced doesn't, and the connection is now broken at this point. Perhaps these errors should both be handled with the `BrokenPipeError` after the freeze. (The refactoring away from py2 compat may not be desireable in the freeze, but this is much easier to read, and obviously correct given the referenced CPython code.) I suspect this is what 6bceecb28806 was attempting to fix, but it wasn't specific about the sporadic errors it was seeing. [1] https://github.com/python/cpython/blob/b2eaa75b176e07730215d76d8dce4d63fb493391/Lib/wsgiref/handlers.py#L139

ci: add a runner for Windows 10 This is currently only manually invoked, and allows for failure because we only have a single runner that takes over 2h for a full run, and there are a handful of flakey tests, plus 3 known failing tests. The system being used here is running MSYS, Python, Visual Studio, etc, as installed by `install-windows-dependencies.ps1`. This script installs everything to a specific directory instead of using the defaults, so we adjust the MinGW shell path to compensate. Additionally, the script doesn't install the launcher `py.exe`. It is possible to adjust the script to install it, but it's an option to an existing python install (instead of a standalone installer), and I've had the whole python install fail and rollback when requested to install the launcher if it detects a newer one is already installed. In short, it is a point of failure for a feature we don't (yet?) need. Unlike other systems where the intepreter name includes the version, everything here is `python.exe`, so they can't all exist on `PATH` and let the script choose the desired one. (The `py.exe` launcher would accomplish, using the registry instead of `PATH`, but that wouldn't allow for venv installs.) Because of this, switch to the absolute path of the python interpreter to be used (in this case a venv created from the py39 install, which is old, but what both pyoxidizer and TortoiseHg currently use). The `RUNTEST_ARGS` hardcodes `-j8` because this system has 4 cores, and therefore runs 4 parallel tests by default. However on Windows, using more parallel tests than cores results in better performance for whatever reason. I don't have an optimal value yet (ideally the runner itself can make the adjustment on Windows), but this results in saving ~15m on a full run that otherwise takes ~2.5h. I'm also not concerned about how it would affect other Windows machines, because we don't have any at this point, and I have no idea when we can get more. As far as system setup goes, the CI is run by a dedicated user that lacks admin rights. The install script was run by an admin user, and then the standard user was configured to use it. If I set this up again, I'd probably give the dedicated user admin rights to run the install script, and reset to standard user rights when done. The python intepreter failed in weird ways when run by the standard user until it was manually reinstalled by the standard user: Fatal Python error: init_fs_encoding: failed to get the Python codec of the filesystem encoding Additionally, changing the environment through the Windows UI prompts to escalate to an admin user, and then setting the user level environment variables like `TEMP` and `PATH` (to try to avoid exceeding the 260 character path limit) didn't actually change the user's environment. (Likely it changed the admin user's environment, but I didn't confirm that.) I ended up having to use the registry editor for the standard user to make those changes.