## Summary
A bug in `requires_python` (which infers the Python requirement from a
marker) was leading us to break an invariant around the relationship
between the marker environment and the Python requirement. This, in
turn, was leading us to drop parts of the environment space when
solving.
Specifically, in the linked example, we generated a fork for
`python_full_version < '3.10' or platform_python_implementation !=
'CPython'`, which was later split into `python_full_version == '3.8.*'`
and `python_full_version == '3.9.*'`, losing the
`platform_python_implementation != 'CPython'` portion.
Closes https://github.com/astral-sh/uv/issues/10669.
## Summary
I don't think this had an impact in practice, but it is "wrong" to omit
these. Confirmed that the cache (for example) now includes the build tag
(as in, `mkl_fft-1.3.8-72-cp310-cp310-manylinux2014_x86_64`).
## Summary
This PR extends the thinking in #10525 to platform tags, and then uses
the structured tag enums everywhere, rather than passing around strings.
I think this is a big improvement! It means we're no longer doing ad hoc
tag parsing all over the place.
## Summary
The idea here is to show both (1) an example of a compatible tag and (2)
the tags that were available, whenever we fail to resolve due to an
abscence of matching wheels.
Closes https://github.com/astral-sh/uv/issues/2777.
## Summary
The assumption that all tags are listed under a flat `.git/ref/tags`
structure was wrong. Git creates a hierarchy of directories for tags
containing slashes. To fix the cache key calculation, we need to
recursively traverse all files under that folder instead.
## Test Plan
1. Create an `uv` project with git-tag cache-keys;
2. Add any tag with slash;
3. Run `uv sync` and see uv_cache_info error in verbose log;
4. `uv sync` doesn't trigger reinstall on next tag addition or removal;
5. With fix applied, reinstall triggers on every tag update and there
are no errors in the log.
Fixes#10467
---------
Co-authored-by: Sergei Nizovtsev <sergei.nizovtsev@eqvilent.com>
Co-authored-by: Charlie Marsh <charlie.r.marsh@gmail.com>
N.B. After fixing #10430, `ArcStr` became the fastest implementation
(and the gains were significantly reduced, down to 1-2%). See:
https://github.com/astral-sh/uv/pull/10453#issuecomment-2583344414.
## Summary
I tried out a variety of small string crates, but `Arc<str>`
outperformed them, giving a ~10% speed-up:
```console
❯ hyperfine "../arcstr lock" "../flexstr lock" "uv lock" "../arc lock" "../compact_str lock" --prepare "rm -f uv.lock" --min-runs 50 --warmup 20
Benchmark 1: ../arcstr lock
Time (mean ± σ): 304.6 ms ± 2.3 ms [User: 302.9 ms, System: 117.8 ms]
Range (min … max): 299.0 ms … 311.3 ms 50 runs
Benchmark 2: ../flexstr lock
Time (mean ± σ): 319.2 ms ± 1.7 ms [User: 317.7 ms, System: 118.2 ms]
Range (min … max): 316.8 ms … 323.3 ms 50 runs
Benchmark 3: uv lock
Time (mean ± σ): 330.6 ms ± 1.5 ms [User: 328.1 ms, System: 139.3 ms]
Range (min … max): 326.6 ms … 334.2 ms 50 runs
Benchmark 4: ../arc lock
Time (mean ± σ): 303.0 ms ± 1.2 ms [User: 301.6 ms, System: 118.4 ms]
Range (min … max): 300.3 ms … 305.3 ms 50 runs
Benchmark 5: ../compact_str lock
Time (mean ± σ): 320.4 ms ± 2.0 ms [User: 318.7 ms, System: 120.8 ms]
Range (min … max): 317.3 ms … 326.7 ms 50 runs
Summary
../arc lock ran
1.01 ± 0.01 times faster than ../arcstr lock
1.05 ± 0.01 times faster than ../flexstr lock
1.06 ± 0.01 times faster than ../compact_str lock
1.09 ± 0.01 times faster than uv lock
```
## Summary
This appears to be a consistent 1% performance improvement and should
also reduce memory quite a bit. We've also decided to use these for
markers, so it's nice to use the same optimization here.
```
❯ hyperfine "./uv pip compile --universal scripts/requirements/airflow.in" "./arcstr pip compile --universal scripts/requirements/airflow.in" --min-runs 50 --warmup 20
Benchmark 1: ./uv pip compile --universal scripts/requirements/airflow.in
Time (mean ± σ): 136.3 ms ± 4.0 ms [User: 139.1 ms, System: 241.9 ms]
Range (min … max): 131.5 ms … 149.5 ms 50 runs
Benchmark 2: ./arcstr pip compile --universal scripts/requirements/airflow.in
Time (mean ± σ): 134.9 ms ± 3.2 ms [User: 137.6 ms, System: 239.0 ms]
Range (min … max): 130.1 ms … 151.8 ms 50 runs
Summary
./arcstr pip compile --universal scripts/requirements/airflow.in ran
1.01 ± 0.04 times faster than ./uv pip compile --universal scripts/requirements/airflow.in
```
This should be essentially the exact same behaviour, but backon is a
total API redesign, so things had to be expressed slightly differently.
Overall I think the code is more readable, which is nice.
Fixes#10001
## Summary
This follows Ruff's design exactly: you can provide a version specifier
(like `>=0.5`), and we'll enforce it at runtime.
Closes https://github.com/astral-sh/uv/issues/8605.
