Georges Racinet <georges.racinet@octobus.net> [Mon, 30 Oct 2023 21:25:28 +0100] rev 51248
rust-index: a property to identify the Rust index as such
Will be useful soon in `mercurial.scmutil` and potentially elsewhere
Georges Racinet <georges.racinet@octobus.net> [Mon, 30 Oct 2023 15:32:33 +0100] rev 51247
rust-cpython-revlog: renamed NodeTree import as CoreNodeTree
We're about to introduce a `NodeTree` Python class (hence also
a Rust struct) and it would be a collision with the import
Georges Racinet <georges.racinet@octobus.net> [Fri, 20 Oct 2023 09:48:53 +0200] rev 51246
rust-index: stop using C index
We still keep its wrapper implementation in `hg-cpython::cindex`,
because we might want to recreate ancestors handling objects using
it for the case of REVLOGV2.
Also, we still instantiate it (from Python code) and store it as
attribute, for the likes of `get_cindex` and the caller that
relies on it, but that is soon to be removed, too.
Georges Racinet <georges.racinet@octobus.net> [Sun, 29 Oct 2023 12:07:05 +0100] rev 51245
rust-index: using `hg::index::Index` in discovery
At this point the C index is not used any more: we had to
remove `pyindex_to_graph()` to avoid the dead code warning.
Georges Racinet on incendie.racinet.fr <georges@racinet.fr> [Sun, 29 Oct 2023 12:01:57 +0100] rev 51244
rust-python-testing: separated base test classes
This will allow, e.g., to change `test-rust-discovery.py` simply
by adding the appropriate base class.
Georges Racinet <georges.racinet@octobus.net> [Sun, 29 Oct 2023 11:21:18 +0100] rev 51243
rust-discovery: encapsulated conversions to vec for instance methods
This new `pyiter_to_vec` is pretty trivial, and only mildly reduces
code duplication. The main advantage is that it encapsulates access
to the `index` attribute, which will be changed when we replace the
C index by the Rust index, given as `PySharedRef`.
Georges Racinet <georges.racinet@octobus.net> [Sun, 29 Oct 2023 11:10:09 +0100] rev 51242
rust-discovery: moving most of hg-cpython methods to regular code blocks
The chosen methods are those with conversion of an incoming Python iterable,
as they will be changed the most when we will remove the C index, and
`takefullsample` for consistency with `takequicksample`.
Georges Racinet <georges.racinet@octobus.net> [Sun, 29 Oct 2023 10:47:54 +0100] rev 51241
rust-index: using `hg::index::Index` in `hg-cpython::dagops`
Hooking `headrevs` to the Rust index is straightforward as long as
we go the `PySharedRef` way. Direct attempts of obtaining a reference
to the inner `hg::index::Index` fail for lifetime reasons: the reference
is bound to the GIL, yet the `as_set` local variable is considered to
be static (the borrow checker clearly does not realize or care that this
set only stores `Revision` values).
In `rank()`, the chosen solution is the simplest as far as `hg-cpython` is
concerned, but it has the defect of removing an implementation
that would be easily adaptable if the core index did implement `RankedGraph`
(returning the same error as long as only `REVLOGV1` is supported), but that
would introduce a direct dependency of `hg-core` on the ``vcsgraph` crate.
Georges Racinet on incendie.racinet.fr <georges@racinet.fr> [Sat, 28 Oct 2023 22:50:10 +0200] rev 51240
rust-index: using `hg::index::Index` in MissingAncestors
With this, the whole `hg-cpython::ancestors` module can now work without
the C index.
Georges Racinet <georges.racinet@octobus.net> [Fri, 27 Oct 2023 22:11:05 +0200] rev 51239
rust-index: using the `hg::index::Index` in ancestors iterator and lazy set
Since there is no Rust implementation for REVLOGV2/CHANGELOGv2, we declare
them to be incompatible with Rust, hence indexes in these formats will use
the implementations from Python `mercurial.ancestor`. If this is an unacceptable
performance hit for current users of these formats, we can later on add Rust
implementations based on the C index for them or implement these formats for
the Rust indexes.
Among the challenges that we had to meet, we wanted to avoid taking the GIL each
time the inner (vcsgraph) iterator has to call the parents function. This would probably
still be acceptable in terms of performance with `AncestorsIterator`, but not with
`LazyAncestors` nor for the upcoming change in `MissingAncestors`.
Hence we enclose the reference to the index in a `PySharedRef`, leading to more
rigourous checking of mutations, which does pass now that there no logically immutable
methods of `hg::index::Index` that take a mutable reference as input.