Recently, rkyv 0.8 was released. Its API is a fair bit simpler now for
higher level uses (like for us in `uv`) and results in us being able to
delete a fair bit of code. This also removes our last dependency on `syn
1.0`, and thus drops that dependency.
Performance (via testing on the `transformers` example) seems to remain
about the same, which is what was expected:
```
$ hyperfine -w5 -r100 'uv lock' 'uv-ag-rkyv-update lock'
Benchmark 1: uv lock
Time (mean ± σ): 55.6 ms ± 6.4 ms [User: 30.4 ms, System: 35.1 ms]
Range (min … max): 43.0 ms … 73.1 ms 100 runs
Benchmark 2: uv-ag-rkyv-update lock
Time (mean ± σ): 56.5 ms ± 7.2 ms [User: 30.5 ms, System: 36.3 ms]
Range (min … max): 39.1 ms … 71.5 ms 100 runs
Summary
uv lock ran
1.02 ± 0.18 times faster than uv-ag-rkyv-update lock
```
Closes#7415
## Summary
If we have a singleton `Range`, we don't need to iterate over the map of
available ranges; instead, we can just get the singleton directly.
Closes#6131.
We currently normalize package and extra names and drop the whitespace
from version specifiers, but we were not normalizing the order of the
specifiers. By sorting them we match the behavior of `packaging` and
become independent of build backends reordering specifiers (#6332).
Surprisingly, the snapshot diff isn't large - most people were already
writing sorted specifiers. Still, this will lead to observable
differences in lockfiles between releases in cases where there are
entries in `requires-dist` that were not previously sorted (while the
total number of `requires-dist` is already small compared to the overall
lockfile).
## Summary
Normalize all `python_version` markers to their equivalent
`python_full_version` form. This avoids false positives in forking
because we currently cannot detect any relationships between the two
forms. It also avoids subtle bugs due to the truncating semantics of
`python_version`. For example, given `requires-python = ">3.12"`, we
currently simplify the marker `python_version <= 3.12` to `false`.
However, the version `3.12.1` will be truncated to `3.12` for
`python_version` comparisons, and thus it satisfies the python
requirement and evaluates to `true`.
It is possible to simplify back to `python_version` when writing markers
to the lockfile. However, the equivalent `python_full_version` markers
are often clearer and easier to simplify, so I lean towards leaving them
as `python_full_version`.
There are *a lot* of snapshot updates from this change. I'd like more
eyes on the transformation logic in `python_version_to_full_version` to
ensure that they are all correct.
Resolves https://github.com/astral-sh/uv/issues/6125.
Warn when there are missing bounds on transitive dependencies with
`--resolution lowest`.
Implemented as a lazy resolution graph check. Dev deps are odd because
they are missing the edge from the root that extras have (they are
currently orphans in the resolution graph), but this is more complex to
solve properly because we can put dev dep information in a `Requirement`
so i special cased them here.
Closes#2797
Should help with #1718
---------
Co-authored-by: Ibraheem Ahmed <ibraheem@ibraheem.ca>
## Summary
This PR rewrites the `MarkerTree` type to use algebraic decision
diagrams (ADD). This has many benefits:
- The diagram is canonical for a given marker function. It is impossible
to create two functionally equivalent marker trees that don't refer to
the same underlying ADD. This also means that any trivially true or
unsatisfiable markers are represented by the same constants.
- The diagram can handle complex operations (conjunction/disjunction) in
polynomial time, as well as constant-time negation.
- The diagram can be converted to a simplified DNF form for user-facing
output.
The new representation gives us a lot more confidence in our marker
operations and simplification, which is proving to be very important
(see https://github.com/astral-sh/uv/pull/5733 and
https://github.com/astral-sh/uv/pull/5163).
Unfortunately, it is not easy to split this PR into multiple commits
because it is a large rewrite of the `marker` module. I'd suggest
reading through the `marker/algebra.rs`, `marker/simplify.rs`, and
`marker/tree.rs` files for the new implementation, as well as the
updated snapshots to verify how the new simplification rules work in
practice. However, a few other things were changed:
- [We now use release-only comparisons for `python_full_version`, where
we previously only did for
`python_version`](https://github.com/astral-sh/uv/blob/ibraheem/canonical-markers/crates/pep508-rs/src/marker/algebra.rs#L522).
I'm unsure how marker operations should work in the presence of
pre-release versions if we decide that this is incorrect.
- [Meaningless marker expressions are now
ignored](https://github.com/astral-sh/uv/blob/ibraheem/canonical-markers/crates/pep508-rs/src/marker/parse.rs#L502).
This means that a marker such as `'x' == 'x'` will always evaluate to
`true` (as if the expression did not exist), whereas we previously
treated this as always `false`. It's negation however, remains `false`.
- [Unsatisfiable markers are written as `python_version <
'0'`](https://github.com/astral-sh/uv/blob/ibraheem/canonical-markers/crates/pep508-rs/src/marker/tree.rs#L1329).
- The `PubGrubSpecifier` type has been moved to the new `uv-pubgrub`
crate, shared by `pep508-rs` and `uv-resolver`. `pep508-rs` also depends
on the `pubgrub` crate for the `Range` type, we probably want to move
`pubgrub::Range` into a separate crate to break this, but I don't think
that should block this PR (cc @konstin).
There is still some remaining work here that I decided to leave for now
for the sake of unblocking some of the related work on the resolver.
- We still use `Option<MarkerTree>` throughout uv, which is unnecessary
now that `MarkerTree::TRUE` is canonical.
- The `MarkerTree` type is now interned globally and can potentially
implement `Copy`. However, it's unclear if we want to add more
information to marker trees that would make it `!Copy`. For example, we
may wish to attach extra and requires-python environment information to
avoid simplifying after construction.
- We don't currently combine `python_full_version` and `python_version`
markers.
- I also have not spent too much time investigating performance and
there is probably some low-hanging fruit. Many of the test cases I did
run actually saw large performance improvements due to the markers being
simplified internally, reducing the stress on the old `normalize`
routine, especially for the extremely large markers seen in
`transformers` and other projects.
Resolves https://github.com/astral-sh/uv/issues/5660,
https://github.com/astral-sh/uv/issues/5179.
To enforce the 100 character line limit in markdown files introduced in
https://github.com/astral-sh/uv/pull/5635, and to automate the
formatting of markdown files, i've added prettier and formatted our
markdown files with it.
I've excluded the changelog and the generated references documentation
from this for having too many changes, but we can also include them.
I'm not particular on which style we use. My main motivations are
(major) not having to reflow markdown files myself anymore and (minor)
consistence between all markdown files. I've chosen prettier for similar
reason as we chose black, it's a single good style that's automated and
shared in the community. I do prefer prettier's style of not breaking
inside of a link name though.
This PR is in two parts, the first adds prettier to CI and documents
using it, while the second actually formats the docs. When merge
conflicts arise, we can drop the last commit and regenerate it with `npx
prettier --prose-wrap always --write BENCHMARKS.md CONTRIBUTING.md
README.md STYLE.md docs/*.md docs/concepts/**/*.md docs/guides/**/*.md
docs/pip/**/*.md`.
---------
Co-authored-by: Zanie Blue <contact@zanie.dev>
## Summary
The current receipt doesn't capture quite enough information. For
example, it doesn't differentiate between editable and non-editable
requirements. This PR instead uses the full `Requirement` type. I think
we should use a custom representation like we do in the lockfile, but
I'm just using the default representation to demonstrate the idea.
## Summary
There are a few ideas at play here:
1. pip always strips versions to the release when evaluating against a
`Requires-Python`, so we now do the same. That means, e.g., using
`3.13.0b0` will be accepted by a project with `Requires-Python: >=
3.13`, which does _not_ adhere to PEP 440 semantics but is somewhat
intuitive.
2. Because we know we'll only be evaluating against release-only
versions, we can use different semantics in PubGrub that let us collapse
ranges. For example, `python_version >= '3.10' or python_version <
'3.10'` can be collapsed to the truthy marker.
Closes https://github.com/astral-sh/uv/issues/4714.
Closes https://github.com/astral-sh/uv/issues/4272.
Closes https://github.com/astral-sh/uv/issues/4719.
## Summary
Given:
```text
numpy >=1.26 ; python_version >= '3.9'
numpy <1.26 ; python_version < '3.9'
```
When resolving for Python 3.8, we need to narrow the `requires-python`
requirement in the top branch of the fork, because `numpy >=1.26` all
require Python 3.9 or later -- but we know (in that branch) that we only
need to _solve_ for Python 3.9 or later.
Closes https://github.com/astral-sh/uv/issues/4669.
## Summary
Simplify and normalize marker expressions in the lockfile. Right now
this does a simple analysis by only looking at related operators at the
same level of precedence. I think anything more complex would be out of
scope.
Resolves https://github.com/astral-sh/uv/issues/4002.
Follow-up to #4016.
This exposes `Range` and `PubGrubSpecifier` from outside the resolver to
use pubgrub's union creating a dependency edge we don't really want.
## Summary
If `Requires-Python` is omitted in `uv lock` or `uv run`, we now warn
and default to `>=` the current minor version.
Closes https://github.com/astral-sh/uv/issues/4050.
This bumps the versions of pep580 and pep440 to coincide with the
crates.io versions. While not strictly the same, the new types in uv us
an `Inner` struct. Practically I've found I'm still able to use the
patched versions, as can seen from the open PR here:
https://github.com/prefix-dev/pixi/pull/1436.
Would be great if this bump can be done so we can keep combining the
types :)
Since we're adding a `Option<MarkerTree>` to `PubGrubPackage`, and since
we just make `PubGrubPackage` implement `Ord`, it follows that we want
`MarkerTree` to also implement `Ord`.
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## Summary
Just fix typos.
While `alpha-numeric` is not really a misspelling:
- it is missing from mainstream curated dictionaries, all of them
suggest `alphanumeric`;
- it is less used than `alphanumeric` (more than ⨉10 less) according to
the Google [Ngram
Viewer](https://books.google.com/ngrams/graph?content=alpha-numeric%2Calphanumeric&year_start=1900&year_end=2019&corpus=en-2019);
- it is [missing from
SCOWL](http://app.aspell.net/lookup?dict=en_US-large;words=alpha-numeric).
## Test Plan
CI jobs.
We would previously show the parsed version when erroring due to
trailing content after a valid version, which can look different than
the input. E.g. when encountering `0.1-bulbasaur`, we would display:
```
after parsing '0.1b0', found 'ulbasaur', which is not part of a valid version
```
With storing the input string instead of the input version, we now show:
```
after parsing '0.1-b', found 'ulbasaur', which is not part of a valid version
```
## Introduction
PEP 621 is limited. Specifically, it lacks
* Relative path support
* Editable support
* Workspace support
* Index pinning or any sort of index specification
The semantics of urls are a custom extension, PEP 440 does not specify
how to use git references or subdirectories, instead pip has a custom
stringly format. We need to somehow support these while still stying
compatible with PEP 621.
## `tool.uv.source`
Drawing inspiration from cargo, poetry and rye, we add `tool.uv.sources`
or (for now stub only) `tool.uv.workspace`:
```toml
[project]
name = "albatross"
version = "0.1.0"
dependencies = [
"tqdm >=4.66.2,<5",
"torch ==2.2.2",
"transformers[torch] >=4.39.3,<5",
"importlib_metadata >=7.1.0,<8; python_version < '3.10'",
"mollymawk ==0.1.0"
]
[tool.uv.sources]
tqdm = { git = "https://github.com/tqdm/tqdm", rev = "cc372d09dcd5a5eabdc6ed4cf365bdb0be004d44" }
importlib_metadata = { url = "https://github.com/python/importlib_metadata/archive/refs/tags/v7.1.0.zip" }
torch = { index = "torch-cu118" }
mollymawk = { workspace = true }
[tool.uv.workspace]
include = [
"packages/mollymawk"
]
[tool.uv.indexes]
torch-cu118 = "https://download.pytorch.org/whl/cu118"
```
See `docs/specifying_dependencies.md` for a detailed explanation of the
format. The basic gist is that `project.dependencies` is what ends up on
pypi, while `tool.uv.sources` are your non-published additions. We do
support the full range or PEP 508, we just hide it in the docs and
prefer the exploded table for easier readability and less confusing with
actual url parts.
This format should eventually be able to subsume requirements.txt's
current use cases. While we will continue to support the legacy `uv pip`
interface, this is a piece of the uv's own top level interface. Together
with `uv run` and a lockfile format, you should only need to write
`pyproject.toml` and do `uv run`, which generates/uses/updates your
lockfile behind the scenes, no more pip-style requirements involved. It
also lays the groundwork for implementing index pinning.
## Changes
This PR implements:
* Reading and lowering `project.dependencies`,
`project.optional-dependencies` and `tool.uv.sources` into a new
requirements format, including:
* Git dependencies
* Url dependencies
* Path dependencies, including relative and editable
* `pip install` integration
* Error reporting for invalid `tool.uv.sources`
* Json schema integration (works in pycharm, see below)
* Draft user-level docs (see `docs/specifying_dependencies.md`)
It does not implement:
* No `pip compile` testing, deprioritizing towards our own lockfile
* Index pinning (stub definitions only)
* Development dependencies
* Workspace support (stub definitions only)
* Overrides in pyproject.toml
* Patching/replacing dependencies
One technically breaking change is that we now require user provided
pyproject.toml to be valid wrt to PEP 621. Included files still fall
back to PEP 517. That means `pip install -r requirements.txt` requires
it to be valid while `pip install -r requirements.txt` with `-e .` as
content falls back to PEP 517 as before.
## Implementation
The `pep508` requirement is replaced by a new `UvRequirement` (name up
for bikeshedding, not particularly attached to the uv prefix). The still
existing `pep508_rs::Requirement` type is a url format copied from pip's
requirements.txt and doesn't appropriately capture all features we
want/need to support. The bulk of the diff is changing the requirement
type throughout the codebase.
We still use `VerbatimUrl` in many places, where we would expect a
parsed/decomposed url type, specifically:
* Reading core metadata except top level pyproject.toml files, we fail a
step later instead if the url isn't supported.
* Allowed `Urls`.
* `PackageId` with a custom `CanonicalUrl` comparison, instead of
canonicalizing urls eagerly.
* `PubGrubPackage`: We eventually convert the `VerbatimUrl` back to a
`Dist` (`Dist::from_url`), instead of remembering the url.
* Source dist types: We use verbatim url even though we know and require
that these are supported urls we can and have parsed.
I tried to make improve the situation be replacing `VerbatimUrl`, but
these changes would require massive invasive changes (see e.g.
https://github.com/astral-sh/uv/pull/3253). A main problem is the ref
`VersionOrUrl` and applying overrides, which assume the same
requirement/url type everywhere. In its current form, this PR increases
this tech debt.
I've tried to split off PRs and commits, but the main refactoring is
still a single monolith commit to make it compile and the tests pass.
## Demo
Adding
d1ae3b85d5/pyproject.json
as json schema (v7) to pycharm for `pyproject.toml`, you can try the IDE
support already:
[dove.webm](c293c272-c80b-459d-8c95-8c46a8d198a1)
In *some* places in our crates, `serde` (and `rkyv`) are optional
dependencies. I believe this was done out of reasons of "good sense,"
that is, it follows a Rust ecosystem pattern where serde integration
tends to be an opt-in crate feature. (And similarly for `rkyv`.)
However, ultimately, `uv` itself requires `serde` and `rkyv` to
function. Since our crates are strictly internal, there are limited
consumers for our crates without `serde` (and `rkyv`) enabled. I think
one possibility is that optional `serde` (and `rkyv`) integration means
that someone can do this:
cargo test -p pep440_rs
And this will run tests _without_ `serde` or `rkyv` enabled. That in
turn could lead to faster iteration time by reducing compile times. But,
I'm not sure this is worth supporting. The iterative compilation times
of
individual crates are probably fast enough in debug mode, even with
`serde` and `rkyv` enabled. Namely, `serde` and `rkyv` themselves
shouldn't need to be re-compiled in most cases. On `main`:
```
from-scratch: `cargo test -p pep440_rs --lib` 0.685
incremental: `cargo test -p pep440_rs --lib` 0.278s
from-scratch: `cargo test -p pep440_rs --features serde,rkyv --lib` 3.948s
incremental: `cargo test -p pep440_rs --features serde,rkyv --lib` 0.321s
```
So while a from-scratch build does take significantly longer, an
incremental build is about the same.
The benefit of doing this change is two-fold:
1. It brings out crates into alignment with "reality." In particular,
some crates were _implicitly_ relying on `serde` being enabled
without explicitly declaring it. This technically means that our
`Cargo.toml`s were wrong in some cases, but it is hard to observe it
because of feature unification in a Cargo workspace.
2. We no longer need to deal with the cognitive burden of writing
`#[cfg_attr(feature = "serde", ...)]` everywhere.
With https://github.com/pubgrub-rs/pubgrub/pull/190, pubgrub attaches
all types to a dependency provider to reduce the number of generics. We
need a dummy dependency provider now to emulate this. On the plus side,
pep440_rs drops its pubgrub dependency.
Add a single job for for fast lint tools. Rustfmt for rust, ruff for
python formatting and linting, prettier avoids inconsistent formatter
changes between pycharm and vscode.
## Summary
This PR adds limited support for PEP 440-compatible local version
testing. Our behavior is _not_ comprehensively in-line with the spec.
However, it does fix by _far_ the biggest practical limitation, and
resolves all the issues that've been raised on uv related to local
versions without introducing much complexity into the resolver, so it
feels like a good tradeoff for me.
I'll summarize the change here, but for more context, see [Andrew's
write-up](https://github.com/astral-sh/uv/issues/1855#issuecomment-1967024866)
in the linked issue.
Local version identifiers are really tricky because of asymmetry.
`==1.2.3` should allow `1.2.3+foo`, but `==1.2.3+foo` should not allow
`1.2.3`. It's very hard to map them to PubGrub, because PubGrub doesn't
think of things in terms of individual specifiers (unlike the PEP 440
spec) -- it only thinks in terms of ranges.
Right now, resolving PyTorch and friends fails, because...
- The user provides requirements like `torch==2.0.0+cu118` and
`torchvision==0.15.1+cu118`.
- We then match those exact versions.
- We then look at the requirements of `torchvision==0.15.1+cu118`, which
includes `torch==2.0.0`.
- Under PEP 440, this is fine, because `torch @ 2.0.0+cu118` should be
compatible with `torch==2.0.0`.
- In our model, though, it's not, because these are different versions.
If we change our comparison logic in various places to allow this, we
risk breaking some fundamental assumptions of PubGrub around version
continuity.
- Thus, we fail to resolve, because we can't accept both `torch @ 2.0.0`
and `torch @ 2.0.0+cu118`.
As compared to the solutions we explored in
https://github.com/astral-sh/uv/issues/1855#issuecomment-1967024866, at
a high level, this approach differs in that we lie about the
_dependencies_ of packages that rely on our local-version-using package,
rather than lying about the versions that exist, or the version we're
returning, etc.
In short:
- When users specify local versions upfront, we keep track of them. So,
above, we'd take note of `torch` and `torchvision`.
- When we convert the dependencies of a package to PubGrub ranges, we
check if the requirement matches `torch` or `torchvision`. If it's
an`==`, we check if it matches (in the above example) for
`torch==2.0.0`. If so, we _change_ the requirement to
`torch==2.0.0+cu118`. (If it's `==` some other version, we return an
incompatibility.)
In other words, we selectively override the declared dependencies by
making them _more specific_ if a compatible local version was specified
upfront.
The net effect here is that the motivating PyTorch resolutions all work.
And, in general, transitive local versions work as expected.
The thing that still _doesn't_ work is: imagine if there were _only_
local versions of `torch` available. Like, `torch @ 2.0.0` didn't exist,
but `torch @ 2.0.0+cpu` did, and `torch @ 2.0.0+gpu` did, and so on.
`pip install torch==2.0.0` would arbitrarily choose one one `2.0.0+cpu`
or `2.0.0+gpu`, and that's correct as per PEP 440 (local version
segments should be completely ignored on `torch==2.0.0`). However, uv
would fail to identify a compatible version. I'd _probably_ prefer to
fix this, although candidly I think our behavior is _ok_ in practice,
and it's never been reported as an issue.
Closes https://github.com/astral-sh/uv/issues/1855.
Closes https://github.com/astral-sh/uv/issues/2080.
Closes https://github.com/astral-sh/uv/issues/2328.
## Summary
This PR attempts to use a similar trick to that we added in
https://github.com/astral-sh/uv/pull/1878, but for post-releases.
In https://github.com/astral-sh/uv/pull/1878, we added a fake "minimum"
version to enable us to treat `< 1.0.0` as _excluding_ pre-releases of
1.0.0.
Today, on `main`, we accept post-releases and local versions in `>
1.0.0`. But per PEP 440, that should _exclude_ post-releases and local
versions, unless the specifier is itself a pre-release, in which case,
pre-releases are allowed (e.g., `> 1.0.0.post0` should allow `>
1.0.0.post1`).
To support this, we add a fake "maximum" version that's greater than all
the post and local releases for a given version. This leverages our last
remaining free bit in the compact representation.
In this context, we already know (as the comment says) that `self` does
not have a local segment, so we don't need to strip it.
This change isn't motivated by anything other than making the code and
comment in sync. For example, when I first looked at it, I wondered
whether the extra stripping was somehow necessary. But it isn't.
Address a few pedantic lints
lints are separated into separate commits so they can be reviewed
individually.
I've not added enforcement for any of these lints, but that could be
added if desirable.
## Summary
Even when pre-releases are "allowed", per PEP 440, `pydantic<2.0.0`
should _not_ include pre-releases. This PR modifies the specifier
translation to treat `pydantic<2.0.0` as `pydantic<2.0.0.min0`, where
`min` is an internal-only version segment that's invisible to users.
Closes https://github.com/astral-sh/uv/issues/1641.
A couple moons ago, I introduced an optimization for version comparisons
by devising a format where *most* versions would be represented by a
single `u64`. This in turn meant most comparisons (of which many are
done during resolution) would be extremely cheap.
Unfortunately, when I did that, I screwed up the preservation of
ordering as defined by the [Version Specifiers spec]. I think I messed
it up because I had originally devised the representation so that we
could pack things like `1.2.3.dev1.post5`, but later realized it would
be better to limit ourselves to a single suffix. However, I never
updated the binary encoding to better match "up to 4 release versions
and up to precisely 1 suffix." Because of that, there were cases where
versions weren't ordered correctly. For example, this fixes a bug where
`1.0a2 < 1.0dev2`, even though all dev releases should order before
pre-releases.
We also update a test so that it catches these kinds of bugs in the
future. (By testing all pairs of versions in a sequence instead of just
the adjacent versions.)
[Version Specifiers spec]:
https://packaging.python.org/en/latest/specifications/version-specifiers/#summary-of-permitted-suffixes-and-relative-ordering
This PR adds initial support for [rkyv] to puffin. In particular,
the main aim here is to make puffin-client's `SimpleMetadata` type
possible to deserialize from a `&[u8]` without doing any copies. This
PR **stops short of actuallying doing that zero-copy deserialization**.
Instead, this PR is about adding the necessary trait impls to a variety
of types, along with a smattering of small refactorings to make rkyv
possible to use.
For those unfamiliar, rkyv works via the interplay of three traits:
`Archive`, `Serialize` and `Deserialize`. The usual flow of things is
this:
* Make a type `T` implement `Archive`, `Serialize` and `Deserialize`.
rkyv
helpfully provides `derive` macros to make this pretty painless in most
cases.
* The process of implementing `Archive` for `T` *usually* creates an
entirely
new distinct type within the same namespace. One can refer to this type
without naming it explicitly via `Archived<T>` (where `Archived` is a
clever
type alias defined by rkyv).
* Serialization happens from `T` to (conceptually) a `Vec<u8>`. The
serialization format is specifically designed to reflect the in-memory
layout
of `Archived<T>`. Notably, *not* `T`. But `Archived<T>`.
* One can then get an `Archived<T>` with no copying (albeit, we will
likely
need to incur some cost for validation) from the previously created
`&[u8]`.
This is quite literally [implemented as a pointer cast][rkyv-ptr-cast].
* The problem with an `Archived<T>` is that it isn't your `T`. It's
something
else. And while there is limited interoperability between a `T` and an
`Archived<T>`, the main issue is that the surrounding code generally
demands
a `T` and not an `Archived<T>`. **This is at the heart of the tension
for
introducing zero-copy deserialization, and this is mostly an intrinsic
problem to the technique and not an rkyv-specific issue.** For this
reason,
given an `Archived<T>`, one can get a `T` back via an explicit
deserialization step. This step is like any other kind of
deserialization,
although generally faster since no real "parsing" is required. But it
will
allocate and create all necessary objects.
This PR largely proceeds by deriving the three aforementioned traits
for `SimpleMetadata`. And, of course, all of its type dependencies. But
we stop there for now.
The main issue with carrying this work forward so that rkyv is actually
used to deserialize a `SimpleMetadata` is figuring out how to deal
with `DataWithCachePolicy` inside of the cached client. Ideally, this
type would itself have rkyv support, but adding it is difficult. The
main difficulty lay in the fact that its `CachePolicy` type is opaque,
not easily constructable and is internally the tip of the iceberg of
a rat's nest of types found in more crates such as `http`. While one
"dumb"-but-annoying approach would be to fork both of those crates
and add rkyv trait impls to all necessary types, it is my belief that
this is the wrong approach. What we'd *like* to do is not just use
rkyv to deserialize a `DataWithCachePolicy`, but we'd actually like to
get an `Archived<DataWithCachePolicy>` and make actual decisions used
the archived type directly. Doing that will require some work to make
`Archived<DataWithCachePolicy>` directly useful.
My suspicion is that, after doing the above, we may want to mush
forward with a similar approach for `SimpleMetadata`. That is, we want
`Archived<SimpleMetadata>` to be as useful as possible. But right
now, the structure of the code demands an eager conversion (and thus
deserialization) into a `SimpleMetadata` and then into a `VersionMap`.
Getting rid of that eagerness is, I think, the next step after dealing
with `DataWithCachePolicy` to unlock bigger wins here.
There are many commits in this PR, but most are tiny. I still encourage
review to happen commit-by-commit.
[rkyv]: https://rkyv.org/
[rkyv-ptr-cast]:
https://docs.rs/rkyv/latest/src/rkyv/util/mod.rs.html#63-68
## Summary
This PR adds a release workflow powered by `cargo-dist`. It's similar to
the version that's PR'd in Ruff
(https://github.com/astral-sh/ruff/pull/9559), with the exception that
it doesn't include the Docker build or the "update dependents" step for
pre-commit.
