Summary:
We've often had cases where we need to nuke peoples caches for various
reasons. It's a hug pain since we haven't a way to communicate with all hg
clients. Now that we have configerator dynamicconfigs, we can use that to reach
all clients.
This diff adds support for configs like:
```
[hgcache-purge]
foo=2020-08-20
```
The key, 'foo' in this case, is an identifier used to only run this purge once.
The value is a date after which this purge will no longer run. This is useful
for bounding the damager from forgetting about a purge and having it delete caches
over and over in the future for new repos or repos where the run once marker
file is deleted for some reason.
Reviewed By: quark-zju
Differential Revision: D23044205
fbshipit-source-id: 8394fcf9ba6df09f391b5317bad134f369e9b416
Any native code (C/C++/Rust) that Mercurial (either core or extensions)
depends on should go here. Python code, or native code that depends on
Python code (e.g. #include <Python.h> or use cpython) is disallowed.
As we start to convert more of Mercurial into Rust, and write new paths
entrirely in native code, we'll want to limit our dependency on Python, which is
why this barrier exists.
See also hgext/extlib/README.md, mercurial/cext/README.mb.
How do I choose between lib and extlib (and cext)?
If your code is native and doesn't depend on Python (awesome!), it goes here.
Otherwise, put it in hgext/extlib (if it's only used by extensions) or
mercurial/cext (if it's used by extensions or core).
a674b25157