feat: support test-groups (#2063)

* feat: support test-groups

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* refactor: address review comments

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* tests: add a integration test

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* Apply suggestions from code review

Co-authored-by: Matthieu Darbois <mayeut@users.noreply.github.com>

* fix: better error messages based on feedback

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

---------

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
Co-authored-by: Matthieu Darbois <mayeut@users.noreply.github.com>

cibuildwheel/projectfiles.py

@@ -4,8 +4,9 @@ import ast
 import configparser
 import contextlib
 from pathlib import Path
+from typing import Any
 
-from ._compat import tomllib
+import dependency_groups
 
 
 def get_parent(node: ast.AST | None, depth: int = 1) -> ast.AST | None:
@@ -84,15 +85,12 @@ def setup_py_python_requires(content: str) -> str | None:
         return None
 
 
-def get_requires_python_str(package_dir: Path) -> str | None:
+def get_requires_python_str(package_dir: Path, pyproject_toml: dict[str, Any] | None) -> str | None:
     """Return the python requires string from the most canonical source available, or None"""
 
     # Read in from pyproject.toml:project.requires-python
-    with contextlib.suppress(FileNotFoundError):
-        with (package_dir / "pyproject.toml").open("rb") as f1:
-            info = tomllib.load(f1)
-        with contextlib.suppress(KeyError, IndexError, TypeError):
-            return str(info["project"]["requires-python"])
+    with contextlib.suppress(KeyError, IndexError, TypeError):
+        return str((pyproject_toml or {})["project"]["requires-python"])
 
     # Read in from setup.cfg:options.python_requires
     config = configparser.ConfigParser()
@@ -106,3 +104,26 @@ def get_requires_python_str(package_dir: Path) -> str | None:
         return setup_py_python_requires(f2.read())
 
     return None
+
+
+def resolve_dependency_groups(
+    pyproject_toml: dict[str, Any] | None, *groups: str
+) -> tuple[str, ...]:
+    """
+    Get the packages in dependency-groups for a package.
+    """
+
+    if not groups:
+        return ()
+
+    if pyproject_toml is None:
+        msg = f"Didn't find a pyproject.toml, so can't read [dependency-groups] {groups!r} from it!"
+        raise FileNotFoundError(msg)
+
+    try:
+        dependency_groups_toml = pyproject_toml["dependency-groups"]
+    except KeyError:
+        msg = f"Didn't find [dependency-groups] in pyproject.toml, which is needed to resolve {groups!r}."
+        raise KeyError(msg) from None
+
+    return dependency_groups.resolve(dependency_groups_toml, *groups)