First, replace all usages in files in-place. I used my editor for this.
If someone wants to add a one-liner that'd be fun.
Then, update directory and file names:
```
# Run twice for nested directories
find . -type d -print0 | xargs -0 rename s/puffin/uv/g
find . -type d -print0 | xargs -0 rename s/puffin/uv/g
# Update files
find . -type f -print0 | xargs -0 rename s/puffin/uv/g
```
Then add all the files again
```
# Add all the files again
git add crates
git add python/uv
# This one needs a force-add
git add -f crates/uv-trampoline
```
## Summary
This PR adds an `--offline` flag to Puffin that disables network
requests (implemented as a Reqwest middleware on our registry client).
When `--offline` is provided, we also allow the HTTP cache to return
stale data.
Closes#942.
Updates our `--no-binary` option and adds a `--only-binary` option for
compatibility with `pip` which uses `:all:`, `:none:` and `<name>` for
specifying packages.
This required adding support for `--only-binary <name>` into our
resolver, previously it was only a boolean toggle.
Retains`--no-build` which is equivalent to `--only-binary :all:`. This
is common enough for safety that I would prefer it is available without
pip's awkward `:all:` syntax.
---------
Co-authored-by: konsti <konstin@mailbox.org>
This PR reduces the stack sizes a windows a little further using the
stack traces from stack overflows combined with looking at the type
sizes. Ultimately, it ignore the three remaining tests failing in debug
on windows due to stack overflows to unblock `cargo test` for windows on
CI.
444 tests run: 444 passed (39 slow), 1 skipped
(Please review this PR commit by commit.)
This PR closes an initial loop on zero-copy deserialization. That
is, provides a way to get a `Archived<SimpleMetadata>` (spelled
`OwnedArchive<SimpleMetadata>` in the code) from a `CachedClient`. The
main benefit of zero-copy deserialization is that we can read bytes
from a file, cast those bytes to a structured representation without
cost, and then start using that type as any other Rust type. The
"catch" is that the structured representation is not the actual type
you started with, but the "archived" version of it.
In order to make all this work, we ended up needing to shave a rather
large yak: we had to re-implement HTTP cache semantics. Previously,
we were using the `http-cache-semantics` crate. While it does support
Serde, it doesn't support `rkyv`. Moreover, even simple support for
`rkyv` wouldn't be enough. What we actually want is for the HTTP cache
semantics to be implemented on the *archived* type so that we can
decide whether our cached response is stale or not without needing to
do a full deserialization into the unarchived type. This is why, in
this PR, you'll see `impl ArchivedCachePolicy { ... }` instead of
`impl CachePolicy { ... }`. (The `derive(rkyv::Archive)` macro
automatically introduces the `ArchivedCachePolicy` type into the
current namespace.)
Unfortunately, this PR does not fully realize the dream that is
zero-copy deserialization. Namely, while a `CachedClient` can now
provide an `OwnedArchive<SimpleMetadata>`, the rest of our code
doesn't really make use of it. Indeed, as soon as we go to build a
`VersionMap`, we eagerly convert our archived metadata into an owned
`SimpleMetadata` via deserialization (that *isn't* zero-copy). After
this change, a lot of the work now shifts to `rkyv` deserialization
and `VersionMap` construction. More precisely, the main thing we drop
here is `CachePolicy` deserialization (which is now truly zero-copy)
and the parsing of the MessagePack format for `SimpleMetadata`. But we
are still paying for deserialization. We're just paying for it in a
different place.
This PR does seem to bring a speed-up, but it is somewhat underwhelming.
My measurements have been pretty noisy, but I get a 1.1x speedup fairly
often:
```
$ hyperfine -w5 "puffin-main pip compile --cache-dir ~/astral/tmp/cache-main ~/astral/tmp/reqs/home-assistant-reduced.in -o /dev/null" "puffin-test pip compile --cache-dir ~/astral/tmp/cache-test ~/astral/tmp/reqs/home-assistant-reduced.in -o /dev/null" ; A kang
Benchmark 1: puffin-main pip compile --cache-dir ~/astral/tmp/cache-main ~/astral/tmp/reqs/home-assistant-reduced.in -o /dev/null
Time (mean ± σ): 164.4 ms ± 18.8 ms [User: 427.1 ms, System: 348.6 ms]
Range (min … max): 131.1 ms … 190.5 ms 18 runs
Benchmark 2: puffin-test pip compile --cache-dir ~/astral/tmp/cache-test ~/astral/tmp/reqs/home-assistant-reduced.in -o /dev/null
Time (mean ± σ): 148.3 ms ± 10.2 ms [User: 357.1 ms, System: 319.4 ms]
Range (min … max): 136.8 ms … 184.4 ms 19 runs
Summary
puffin-test pip compile --cache-dir ~/astral/tmp/cache-test ~/astral/tmp/reqs/home-assistant-reduced.in -o /dev/null ran
1.11 ± 0.15 times faster than puffin-main pip compile --cache-dir ~/astral/tmp/cache-main ~/astral/tmp/reqs/home-assistant-reduced.in -o /dev/null
```
One downside is that this does increase cache size (`rkyv`'s
serialization format is not as compact as MessagePack). On disk size
increases by about 1.8x for our `simple-v0` cache.
```
$ sort-filesize cache-main
4.0K cache-main/CACHEDIR.TAG
4.0K cache-main/.gitignore
8.0K cache-main/interpreter-v0
8.7M cache-main/wheels-v0
18M cache-main/archive-v0
59M cache-main/simple-v0
109M cache-main/built-wheels-v0
193M cache-main
193M total
$ sort-filesize cache-test
4.0K cache-test/CACHEDIR.TAG
4.0K cache-test/.gitignore
8.0K cache-test/interpreter-v0
8.7M cache-test/wheels-v0
18M cache-test/archive-v0
107M cache-test/simple-v0
109M cache-test/built-wheels-v0
242M cache-test
242M total
```
Also, while I initially intended to do a simplistic implementation of
HTTP cache semantics, I found that everything was somewhat
inter-connected. I could have wrote code that _specifically_ only worked
with the present behavior of PyPI, but then it would need to be special
cased and everything else would need to continue to use
`http-cache-sematics`. By implementing what we need based on what Puffin
actually is (which is still less than what `http-cache-semantics` does),
we can avoid special casing and use zero-copy deserialization for our
cache policy in _all_ cases.
## Summary
Oops -- this was using a different cache key than the route above (this
is the wheel _metadata_ route vs. the wheel build route), so we were
saving and building source distributions twice in `pip install`.
This PR migrates our source distribution downloads to unzip as we
stream, similar to our approach for wheels.
In my testing, this showed a consistent speedup (e.g., 6% here for a few
representative source distributions):
```text
❯ python -m scripts.bench --puffin-path ./target/release/main --puffin-path ./target/release/puffin --benchmark install-cold requirements.in
Benchmark 1: ./target/release/main (install-cold)
Time (mean ± σ): 1.503 s ± 0.039 s [User: 1.479 s, System: 0.537 s]
Range (min … max): 1.466 s … 1.605 s 10 runs
Benchmark 2: ./target/release/puffin (install-cold)
Time (mean ± σ): 1.421 s ± 0.024 s [User: 1.505 s, System: 0.593 s]
Range (min … max): 1.381 s … 1.454 s 10 runs
Summary
'./target/release/puffin (install-cold)' ran
1.06 ± 0.03 times faster than './target/release/main (install-cold)'
```
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
Use a single error type in `puffin_distribution`, rather than two
confusingly similar types between `DistributionDatabase` and the source
distribution module.
Also removes the `#[from]` for IO errors and replaces with explicit
wrapping, which is verbose but removes a bunch of incorrect error
messages.
This PR changes the error type to be boxed internally so that it uses
less size on the stack. This makes functions returning `Result<T,
Error>`, in particular, return something much smaller.
The specific thing that motivated this was Clippy lints firing when I
tried to refactor code in this crate.
I chose to achieve boxing by splitting the enum out into a separate
type, and then wiring up the necessary `From` impl to make error
conversions easy, and then making `Error` itself opaque. We could expose
the `Box`, but there isn't a ton of benefit in doing so because one
cannot pattern match through a `Box`.
This required using more explicit error conversions in several places.
And as a result, I was able to remove all `#[from]` attributes on
non-transparent error variants.
## Summary
When we unzip wheels in the cache, we write the directories out to an
`archive-v0` bucket, and then symlink into that bucket from the
`wheels-v0` and `built-wheels-v0` buckets.
On Windows, symlinks are not well supported. Specifically, they need to
be explicitly enabled by the user. So, instead of symlinks, we now use
junctions, which are well-supported on Windows, and allow you to
(effectively) symlink a directory to another directory. This PR
implements said junction support, which gets the core installer working
on Windows.
In the past, we also used symlinks to implement another primitive: we
wanted to be able to replace a directory "atomically" (I put
"atomically" in quotes because I don't know if it's actually a
guaranteed atomic operation), in case someone was trying to use the
directory while we were replacing it (as opposed to deleting the
directory, then moving it into place).
On Windows, it doesn't appear to be possible to atomically replace a
junction. So instead, I'm using a new design, whereby the cache always
returns canonicalized paths. We know these canonicalized paths are
unique and won't be replaced, so they're safe for writers to rely on. In
general, when we write new data to the cache, we now return the
canonicalized path. When we read from the cache, and try to identify
(e.g.) the set of wheels available to us, we canonicalize the links
immediately and consider them non-existent if that operation fails.
Closes#1085.
---------
Co-authored-by: konstin <konstin@mailbox.org>
## Summary
It turns out this is significantly faster when reading (e.g.) _just_ the
`METADATA` file from a zipped wheel.
I audited other `File::open` usages, and everything else seems to be
using a buffered reader already (directly, or in whatever third-party
crate it's passed to) _or_ is read immediately in full.
See the criterion benchmark:
```
file_reader/numpy-1.26.3-pp39-pypy39_pp73-manylinux_2_17_x86_64.manylinux2014_x86_64.whl
time: [6.9618 ms 6.9664 ms 6.9713 ms]
Found 4 outliers among 100 measurements (4.00%)
4 (4.00%) high mild
file_reader/flask-3.0.1-py3-none-any.whl
time: [237.50 µs 238.25 µs 239.13 µs]
Found 7 outliers among 100 measurements (7.00%)
3 (3.00%) high mild
4 (4.00%) high severe
buffered_reader/numpy-1.26.3-pp39-pypy39_pp73-manylinux_2_17_x86_64.manylinux2014_x86_64.whl
time: [648.92 µs 653.85 µs 660.09 µs]
Found 4 outliers among 100 measurements (4.00%)
3 (3.00%) high mild
1 (1.00%) high severe
buffered_reader/flask-3.0.1-py3-none-any.whl
time: [39.578 µs 39.712 µs 39.869 µs]
Found 8 outliers among 100 measurements (8.00%)
3 (3.00%) high mild
5 (5.00%) high severe
```
## Summary
This PR uses `ctime` consistently on Unix as a more conservative
approach to change detection. It also ensures that our timestamp
abstraction is entirely internal, so we can change the representation
and logic easily across the codebase in the future.
## Summary
This PR is an alternative approach to #949 which should be much safer.
As in #949, we add a `Refresh` policy to the cache. However, instead of
deleting entries from the cache the first time we read them, we now
check if the entry is sufficiently new (created after the start of the
command) if the refresh policy applies. If the entry is stale, then we
avoid reading it and continue onward, relying on the cache to
appropriately overwrite based on "new" data. (This relies on the
preceding PRs, which ensure the cache is append-only, and ensure that we
can atomically overwrite.)
Unfortunately, there are just a lot of paths through the cache, and
didn't data is handled with different policies, so I really had to go
through and consider the "right" behavior for each case. For example,
the HTTP requests can use `max-age=0, must-revalidate`. But for the
routes that are based on filesystem modification, we need to do
something slightly different.
Closes#945.
## Summary
One problem we have in the cache today is that we can't overwrite
entries atomically, because we store unzipped _directories_ in the cache
(which makes installation _much_ faster than storing zipped
directories). So, if you ignore the existing contents of the cache when
writing, you might run into an error, because you might attempt to write
a directory where a directory already exists.
This is especially annoying for cache refresh, because in order to
refresh the cache, we have to purge it (i.e., delete a bunch of stuff),
which is also highly unsafe if Puffin is running across multiple threads
or multiple processes.
The solution I'm proposing here is that whenever we persist a
_directory_ to the cache, we persist it to a special "archive" bucket.
Then, within the other buckets, directory entries are actually symlinks
into that "archive" bucket. With symlinks, we can atomically replace,
which means we can easily overwrite cache entries without having to
delete from the cache.
The main downside is that we'll now accumulate dangling entries in the
"archive" bucket, and so we'll need to implement some form of garbage
collection to ensure that we remove entries with no symlinks. Another
downside is that cache reads and writes will be a bit slower, since we
need to deal with creating and resolving these symlinks.
As an example... after this change, the cache entry for this unzipped
wheel is actually a symlink:

Then, within the archive directory, we actually have two unique entries
(since I intentionally ran the command twice to ensure overwrites were
safe):

Per https://apenwarr.ca/log/20181113, `ctime` should be a lot more
conservative, and should detect things like the issue we see with the
python-build-standalone builds, where the `mtime` is identical across
builds.
On Windows, I'm just using `last_write_time`. But we should probably add
`volume_serial_number` and other attributes via
[`winapi_util`](https://docs.rs/winapi-util/latest/winapi_util/index.html).
## Summary
This is a refactor of the source distribution cache that again aims to
make the cache purely additive. Instead of deleting all built wheels
when the cache gets invalidated (e.g., because the source distribution
changed on PyPI or something), we now treat each invalidation as its own
cache directory. The manifest inside of the source distribution
directory now becomes a pointer to the "latest" version of the source
distribution cache.
Here's a visual example:

With this change, we avoid deleting built distributions that might be
relied on elsewhere and maintain our invariant that the cache is purely
additive. The cost is that we now preserve stale wheels, but we should
add a garbage collection mechanism to deal with that.
## Summary
This PR gets rid of the manifest that we store for source distributions.
Historically, that manifest included the source distribution metadata,
plus a list of built wheels.
The problem with the manifest is that it duplicates state, since we now
have to look at both the manifest and the filesystem to understand the
cache state. Instead, I think we should treat the cache as the source of
truth, and get rid of the duplicated state in the manifest.
Now, we store the manifest (which is merely used to check for cache
freshness -- in future PRs, I will repurpose it though, so I left it
around), then the distribution metadata as its own file, then any
distributions in the same directory. When we want to see if there are
any valid distributions, we `readdir` on the directory. This is also
much more consistent with how the install plan works.
This is https://github.com/astral-sh/puffin/pull/947 again but this time
merging into main instead of downstack, sorry for the noise.
---
Windows has a default stack size of 1MB, which makes puffin often fail
with stack overflows. The PR reduces stack size by three changes:
* Boxing `File` in `Dist`, reducing the size from 496 to 240.
* Boxing the largest futures.
* Boxing `CachePolicy`
## Method
Debugging happened on linux using
https://github.com/astral-sh/puffin/pull/941 to limit the stack size to
1MB. Used ran the command below.
```
RUSTFLAGS=-Zprint-type-sizes cargo +nightly build -p puffin-cli -j 1 > type-sizes.txt && top-type-sizes -w -s -h 10 < type-sizes.txt > sizes.txt
```
The main drawback is top-type-sizes not saying what the `__awaitee` is,
so it requires manually looking up with a future with matching size.
When the `brotli` features on `reqwest` is active, a lot of brotli types
show up. Toggling this feature however seems to have no effect. I assume
they are false positives since the `brotli` crate has elaborate control
about allocation. The sizes are therefore shown with the feature off.
## Results
The largest future goes from 12208B to 6416B, the largest type
(`PrioritizedDistribution`, see also #948) from 17448B to 9264B. Full
diff: https://gist.github.com/konstin/62635c0d12110a616a1b2bfcde21304f
For the second commit, i iteratively boxed the largest file until the
tests passed, then with an 800KB stack limit looked through the
backtrace of a failing test and added some more boxing.
Quick benchmarking showed no difference:
```console
$ hyperfine --warmup 2 "target/profiling/main-dev resolve meine_stadt_transparent" "target/profiling/puffin-dev resolve meine_stadt_transparent"
Benchmark 1: target/profiling/main-dev resolve meine_stadt_transparent
Time (mean ± σ): 49.2 ms ± 3.0 ms [User: 39.8 ms, System: 24.0 ms]
Range (min … max): 46.6 ms … 63.0 ms 55 runs
Warning: Statistical outliers were detected. Consider re-running this benchmark on a quiet system without any interferences from other programs. It might help to use the '--warmup' or '--prepare' options.
Benchmark 2: target/profiling/puffin-dev resolve meine_stadt_transparent
Time (mean ± σ): 47.4 ms ± 3.2 ms [User: 41.3 ms, System: 20.6 ms]
Range (min … max): 44.6 ms … 60.5 ms 62 runs
Warning: Statistical outliers were detected. Consider re-running this benchmark on a quiet system without any interferences from other programs. It might help to use the '--warmup' or '--prepare' options.
Summary
target/profiling/puffin-dev resolve meine_stadt_transparent ran
1.04 ± 0.09 times faster than target/profiling/main-dev resolve meine_stadt_transparent
```
## Summary
I got confused by why `VerbatimUrl` was on `Path`. Since it's directly
computed from it, I think we should just compute it as-needed. I think
it's also possibly-buggy because the URL is the URL of the _directory_,
not the artifact itself, which differs from other distributions.
## Summary
This is a small correctness improvement that ensures that we avoid using
stale cache entries for local dependencies in the install plan. We
already have some logic like this in the source distribution builder,
but it didn't apply in the install plan, and so we'd end up using stale
wheels.
Specifically, now, if you create a new local wheel, and run `pip sync`,
we'll mark the cache entries as stale and make sure we unzip it and
install it. (If the wheel is _already_ installed, we won't reinstall it
though, which will be a separate change. This is just about reading from
the cache, not the environment.)
## Summary
It turns out that storing an absolute URL for every file caused a
significant performance regression. This PR attempts to address the
regression with two changes.
The first is that we now store the raw string if the URL is an absolute
URL. If the URL is relative, we store the base URL alongside the raw
relative string. As such, we avoid serializing and deserializing URLs
until we need them (later on), except for the base URL.
The second is that we now use the internal `Url` crate methods for
serializing and deserializing. If you look inside `Url`, its standard
serializer and deserialization actually convert it to a string, then
parse the string. But the crate exposes some other methods for faster
serialization and deserialization (with fewer guarantees). I think this
is totally fine since the cache is entirely internal.
If we _just_ change the `Url` serialization (and no other code -- so
continue to store URLs for every file), then the regression goes down to
about 5%:
```shell
❯ python -m scripts.bench \
--puffin-path ./target/release/main \
--puffin-path ./target/release/relative --puffin-path ./target/release/puffin \
scripts/requirements/home-assistant.in --benchmark resolve-warm
Benchmark 1: ./target/release/main (resolve-warm)
Time (mean ± σ): 496.3 ms ± 4.3 ms [User: 452.4 ms, System: 175.5 ms]
Range (min … max): 487.3 ms … 502.4 ms 10 runs
Benchmark 2: ./target/release/relative (resolve-warm)
Time (mean ± σ): 284.8 ms ± 2.1 ms [User: 245.8 ms, System: 165.6 ms]
Range (min … max): 280.3 ms … 288.0 ms 10 runs
Benchmark 3: ./target/release/puffin (resolve-warm)
Time (mean ± σ): 300.4 ms ± 3.2 ms [User: 255.5 ms, System: 178.1 ms]
Range (min … max): 295.4 ms … 305.1 ms 10 runs
Summary
'./target/release/relative (resolve-warm)' ran
1.05 ± 0.01 times faster than './target/release/puffin (resolve-warm)'
1.74 ± 0.02 times faster than './target/release/main (resolve-warm)'
```
So I considered _just_ making that change. But 5% is kind of
borderline...
With both of these changes, the regression is down to 1-2%:
```
Benchmark 1: ./target/release/relative (resolve-warm)
Time (mean ± σ): 282.6 ms ± 7.4 ms [User: 244.6 ms, System: 181.3 ms]
Range (min … max): 275.1 ms … 318.5 ms 30 runs
Benchmark 2: ./target/release/puffin (resolve-warm)
Time (mean ± σ): 286.8 ms ± 2.2 ms [User: 247.0 ms, System: 169.1 ms]
Range (min … max): 282.3 ms … 290.7 ms 30 runs
Summary
'./target/release/relative (resolve-warm)' ran
1.01 ± 0.03 times faster than './target/release/puffin (resolve-warm)'
```
It's consistently ~2%-ish, but at this point it's unclear if that's due
to the URL change or something other change between now and then.
Closes#943.
Add directory `--find-links` support for local paths to pip-compile.
It seems that pip joins all sources and then picks the best package. We
explicitly give find links packages precedence if the same exists on an
index and locally by prefilling the `VersionMap`, otherwise they are
added as another index and the existing rules of precedence apply.
Internally, the feature is called _flat index_, which is more meaningful
than _find links_: We're not looking for links, we're picking up local
directories, and (TBD) support another index format that's just a flat
list of files instead of a nested index.
`RegistryBuiltDist` and `RegistrySourceDist` now use `WheelFilename` and
`SourceDistFilename` respectively. The `File` inside `RegistryBuiltDist`
and `RegistrySourceDist` gained the ability to represent both a url and
a path so that `--find-links` with a url and with a path works the same,
both being locked as `<package_name>@<version>` instead of
`<package_name> @ <url>`. (This is more of a detail, this PR in general
still work if we strip that and have directory find links represented as
`<package_name> @ file:///path/to/file.ext`)
`PrioritizedDistribution` and `FlatIndex` have been moved to locations
where we can use them in the upstack PR.
I added a `scripts/wheels` directory with stripped down wheels to use
for testing.
We're lacking tests for correct tag priority precedence with flat
indexes, i only confirmed this manually since it is not covered in the
pip-compile or pip-sync output.
Closes#876
There is no guarantee that indexes provide hashes at all or the sha256
we support specifically. [PEP
503](https://peps.python.org/pep-0503/#specification):
> The URL SHOULD include a hash in the form of a URL fragment with the
following syntax: #<hashname>=<hashvalue>, where <hashname> is the
lowercase name of the hash function (such as sha256) and <hashvalue> is
the hex encoded digest.
We instead use the url as input to generate a hash when caching.
Previously, the url on file could either be a relative or an absolute
url, depending on the index, and we would finalize it lazily. Now we
finalize the url when converting `pypi_types::File` to
`distribution_types::File`. This change is required to make the hashes
on `File` optional (https://github.com/astral-sh/puffin/pull/910), which
are currently the only unique field usable for caching.
## Summary
This PR adds support for `prepare_metadata_for_build_wheel`, which
allows us to determine source distribution metadata without building the
source distribution. This represents an optimization for the resolver,
as we can skip the expensive build phase for build backends that support
it.
For reference, `prepare_metadata_for_build_wheel` seems to be supported
by:
- `hatchling` (as of
[1.0.9](https://hatch.pypa.io/latest/history/hatchling/#hatchling-v1.9.0)).
- `flit`
- `setuptools`
In fact, it seems to work for every backend _except_ those using legacy
`setup.py`.
Closes#599.
## Summary
Right now, both the callback _and_ the "We have no compatible wheel"
paths have a lot of repeated code. This PR changes the callback to
_just_ remove all the wheels and handle the download, and the rest of
the method following the callback is responsible for finding and
building any wheels.