feat: helper to get dependency-groups

.pre-commit-config.yaml

@@ -37,6 +37,7 @@ repos:
         files: ^nox/
         args: []
         additional_dependencies:
+          - dependency-groups>=1.2
           - jinja2
           - packaging
           - importlib_metadata

nox/project.py

@@ -6,7 +6,9 @@
 from pathlib import Path
 from typing import TYPE_CHECKING
 
+import packaging.requirements
 import packaging.specifiers
+from dependency_groups import resolve
 
 if TYPE_CHECKING:
     from typing import Any
@@ -17,7 +19,7 @@
     import tomllib
 
 
-__all__ = ["load_toml", "python_versions"]
+__all__ = ["load_toml", "python_versions", "dependency_groups"]
 
 
 def __dir__() -> list[str]:
@@ -127,3 +129,20 @@ def python_versions(
     max_minor_version = int(max_version.split(".")[1])
 
     return [f"3.{v}" for v in range(min_minor_version, max_minor_version + 1)]
+
+
+def dependency_groups(pyproject: dict[str, Any], *groups: str) -> tuple[str, ...]:
+    """
+    Get a list of dependencies from a ``[dependency-groups]`` section(s).
+
+    Example:
+
+    .. code-block:: python
+
+        @nox.session
+        def test(session):
+            pyproject = nox.project.load_toml("pyproject.toml")
+            session.install(*nox.project.dependency_groups(pyproject, "dev"))
+    """
+    dep_groups = pyproject["dependency-groups"]
+    return resolve(dep_groups, *groups)

pyproject.toml

@@ -41,6 +41,7 @@ classifiers = [
 dependencies = [
   "argcomplete<4,>=1.9.4",
   "colorlog<7,>=2.6.1",
+  "dependency-groups>=1.1",
   "packaging>=20.9",
   "tomli>=1; python_version<'3.11'",
   "virtualenv>=20.14.1",

tests/test_project.py

@@ -1,6 +1,6 @@
 import pytest
 
-from nox.project import python_versions
+from nox.project import dependency_groups, python_versions
 
 
 def test_classifiers():
@@ -63,3 +63,34 @@ def test_python_range_no_min():
 
     with pytest.raises(ValueError, match="No minimum version found"):
         python_versions(pyproject, max_version="3.5")
+
+
+def test_dependency_groups():
+    example = {
+        "dependency-groups": {
+            "test": ["pytest", "coverage"],
+            "docs": ["sphinx", "sphinx-rtd-theme"],
+            "typing": ["mypy", "types-requests"],
+            "typing-test": [
+                {"include-group": "typing"},
+                {"include-group": "test"},
+                "useful-types",
+            ],
+        }
+    }
+
+    assert dependency_groups(example, "test") == ("pytest", "coverage")
+    assert dependency_groups(example, "typing-test") == (
+        "mypy",
+        "types-requests",
+        "pytest",
+        "coverage",
+        "useful-types",
+    )
+    assert dependency_groups(example, "typing_test") == (
+        "mypy",
+        "types-requests",
+        "pytest",
+        "coverage",
+        "useful-types",
+    )