uv/crates/pep508-rs
konsti a89e146107
Initial workspace support (#3705)
Add workspace support when using `-r <path>/pyproject.toml` or `-e
<path>` in the pip interface. It is limited to all-editable
static-metadata workspaces, and tests only include a single main
workspace, ignoring path dependencies in another workspace. This can be
considered the MVP for workspace support: You can create a workspace,
you can install from it, but some options and conveniences are still
missing. I'll file follow-up tickets (support in lockfiles, support path
deps in other workspace, #3625)

There is also support in `uv run`, but we need
https://github.com/astral-sh/uv/issues/3700 first to properly support
using different current projects in the bluejay interface, currently the
resolution and therefore the lockfile depends on the current project.
I'd do this change first (it's big enough already), then #3700, and then
add workspace support properly to bluejay.

Fixes #3404
2024-05-28 07:41:53 +00:00
..
src Initial workspace support (#3705) 2024-05-28 07:41:53 +00:00
Cargo.lock Copy over pep508-rs crate (#31) 2023-10-06 20:12:19 -04:00
Cargo.toml feat: bump pep580 and pep440 types (#3860) 2024-05-27 09:38:39 +02:00
License-Apache Copy over pep508-rs crate (#31) 2023-10-06 20:12:19 -04:00
License-BSD Copy over pep508-rs crate (#31) 2023-10-06 20:12:19 -04:00
Readme.md Copy over pep508-rs crate (#31) 2023-10-06 20:12:19 -04:00

Dependency specifiers (PEP 508) in Rust

Crates.io PyPI

A library for python dependency specifiers, better known as PEP 508.

Usage

In Rust

use std::str::FromStr;
use pep508_rs::Requirement;

let marker = r#"requests [security,tests] >= 2.8.1, == 2.8.* ; python_version > "3.8""#;
let dependency_specification = Requirement::from_str(marker).unwrap();
assert_eq!(dependency_specification.name, "requests");
assert_eq!(dependency_specification.extras, Some(vec!["security".to_string(), "tests".to_string()]));

In Python

from pep508_rs import Requirement

requests = Requirement(
    'requests [security,tests] >= 2.8.1, == 2.8.* ; python_version > "3.8"'
)
assert requests.name == "requests"
assert requests.extras == ["security", "tests"]
assert [str(i) for i in requests.version_or_url] == [">= 2.8.1", "== 2.8.*"]

Python bindings are built with maturin, but you can also use the normal pip install .

Version and VersionSpecifier from pep440_rs are reexported to avoid type mismatches.

Markers

Markers allow you to install dependencies only in specific environments (python version, operating system, architecture, etc.) or when a specific feature is activated. E.g. you can say importlib-metadata ; python_version < "3.8" or itsdangerous (>=1.1.0) ; extra == 'security'. Unfortunately, the marker grammar has some oversights (e.g. https://github.com/pypa/packaging.python.org/pull/1181) and the design of comparisons (PEP 440 comparisons with lexicographic fallback) leads to confusing outcomes. This implementation tries to carefully validate everything and emit warnings whenever bogus comparisons with unintended semantics are made.

In python, warnings are by default sent to the normal python logging infrastructure:

from pep508_rs import Requirement, MarkerEnvironment

env = MarkerEnvironment.current()
assert not Requirement("numpy; extra == 'science'").evaluate_markers(env, [])
assert Requirement("numpy; extra == 'science'").evaluate_markers(env, ["science"])
assert not Requirement(
    "numpy; extra == 'science' and extra == 'arrays'"
).evaluate_markers(env, ["science"])
assert Requirement(
    "numpy; extra == 'science' or extra == 'arrays'"
).evaluate_markers(env, ["science"])
from pep508_rs import Requirement, MarkerEnvironment

env = MarkerEnvironment.current()
Requirement("numpy; python_version >= '3.9.'").evaluate_markers(env, [])
# This will log: 
# "Expected PEP 440 version to compare with python_version, found '3.9.', "
# "evaluating to false: Version `3.9.` doesn't match PEP 440 rules"