Don't constrain build-system.requires with our dependency-versions

cibuildwheel/platforms/ios.py

@@ -33,9 +33,7 @@
 )
 from ..util.helpers import prepare_command, unwrap_preserving_paragraphs
 from ..util.packaging import (
-    combine_constraints,
     find_compatible_wheel,
-    get_pip_version,
 )
 from ..venv import constraint_flags, virtualenv
 from .macos import install_cpython as install_build_cpython
@@ -461,7 +459,6 @@ def build(options: Options, tmp_path: Path) -> None:
                 build_frontend=build_frontend.name,
                 xbuild_tools=build_options.xbuild_tools,
             )
-            pip_version = get_pip_version(env)
 
             compatible_wheel = find_compatible_wheel(built_wheels, config.identifier)
             if compatible_wheel:
@@ -489,11 +486,6 @@ def build(options: Options, tmp_path: Path) -> None:
                     build_frontend, build_options.build_verbosity, build_options.config_settings
                 )
 
-                build_env = env.copy()
-                build_env["VIRTUALENV_PIP"] = pip_version
-                if constraints_path:
-                    combine_constraints(build_env, constraints_path, None)
-
                 match build_frontend.name:
                     case "pip":
                         # Path.resolve() is needed. Without it pip wheel may try to
@@ -508,7 +500,7 @@ def build(options: Options, tmp_path: Path) -> None:
                             f"--wheel-dir={built_wheel_dir}",
                             "--no-deps",
                             *extra_flags,
-                            env=build_env,
+                            env=env,
                         )
                     case "build":
                         call(
@@ -519,7 +511,7 @@ def build(options: Options, tmp_path: Path) -> None:
                             "--wheel",
                             f"--outdir={built_wheel_dir}",
                             *extra_flags,
-                            env=build_env,
+                            env=env,
                         )
                     case _:
                         assert_never(build_frontend)
@@ -537,9 +529,7 @@ def build(options: Options, tmp_path: Path) -> None:
                 elif config.arch != os.uname().machine:
                     log.step("Skipping tests on non-native simulator architecture")
                 else:
-                    test_env = build_options.test_environment.as_dictionary(
-                        prev_environment=build_env
-                    )
+                    test_env = build_options.test_environment.as_dictionary(prev_environment=env)
 
                     if build_options.before_test:
                         before_test_prepared = prepare_command(

cibuildwheel/platforms/macos.py

@@ -32,7 +32,7 @@
     move_file,
 )
 from ..util.helpers import prepare_command, unwrap
-from ..util.packaging import combine_constraints, find_compatible_wheel, get_pip_version
+from ..util.packaging import find_compatible_wheel, get_pip_version
 from ..venv import constraint_flags, find_uv, virtualenv
 
 
@@ -461,12 +461,6 @@ def build(options: Options, tmp_path: Path) -> None:
                 )
 
                 build_env = env.copy()
-                if pip_version is not None:
-                    build_env["VIRTUALENV_PIP"] = pip_version
-                if constraints_path:
-                    combine_constraints(
-                        build_env, constraints_path, identifier_tmp_dir if use_uv else None
-                    )
 
                 match build_frontend.name:
                     case "pip":

cibuildwheel/platforms/pyodide.py

@@ -32,7 +32,7 @@
     move_file,
 )
 from ..util.helpers import prepare_command, unwrap, unwrap_preserving_paragraphs
-from ..util.packaging import combine_constraints, find_compatible_wheel, get_pip_version
+from ..util.packaging import find_compatible_wheel, get_pip_version
 from ..util.python_build_standalone import (
     PythonBuildStandaloneError,
     create_python_build_standalone_environment,
@@ -419,17 +419,13 @@ def build(options: Options, tmp_path: Path) -> None:
                     build_frontend, build_options.build_verbosity, build_options.config_settings
                 )
 
-                build_env = env.copy()
-                if constraints_path:
-                    combine_constraints(build_env, constraints_path, identifier_tmp_dir)
-                build_env["VIRTUALENV_PIP"] = pip_version
                 call(
                     "pyodide",
                     "build",
                     build_options.package_dir,
                     f"--outdir={built_wheel_dir}",
                     *extra_flags,
-                    env=build_env,
+                    env=env,
                 )
                 built_wheel = next(built_wheel_dir.glob("*.whl"))
 

cibuildwheel/platforms/windows.py

@@ -23,7 +23,7 @@
 from ..util.cmd import call, shell
 from ..util.file import CIBW_CACHE_PATH, copy_test_sources, download, extract_zip, move_file
 from ..util.helpers import prepare_command, unwrap
-from ..util.packaging import combine_constraints, find_compatible_wheel, get_pip_version
+from ..util.packaging import find_compatible_wheel, get_pip_version
 from ..venv import constraint_flags, find_uv, virtualenv
 
 
@@ -461,13 +461,6 @@ def build(options: Options, tmp_path: Path) -> None:
                     shell("graalpy -m pip install setuptools wheel", env=env)
                     extra_flags = [*extra_flags, "-n"]
 
-                build_env = env.copy()
-                if pip_version is not None:
-                    build_env["VIRTUALENV_PIP"] = pip_version
-
-                if constraints_path:
-                    combine_constraints(build_env, constraints_path, identifier_tmp_dir)
-
                 match build_frontend.name:
                     case "pip":
                         # Path.resolve() is needed. Without it pip wheel may try to fetch package from pypi.org
@@ -481,7 +474,7 @@ def build(options: Options, tmp_path: Path) -> None:
                             f"--wheel-dir={built_wheel_dir}",
                             "--no-deps",
                             *extra_flags,
-                            env=build_env,
+                            env=env,
                         )
                     case "build" | "build[uv]":
                         if (
@@ -499,7 +492,7 @@ def build(options: Options, tmp_path: Path) -> None:
                             "--wheel",
                             f"--outdir={built_wheel_dir}",
                             *extra_flags,
-                            env=build_env,
+                            env=env,
                         )
                     case _:
                         assert_never(build_frontend)

cibuildwheel/util/packaging.py

@@ -1,5 +1,5 @@
 import shlex
-from collections.abc import Mapping, MutableMapping, Sequence
+from collections.abc import Mapping, Sequence
 from dataclasses import dataclass, field
 from pathlib import Path, PurePath
 from typing import Any, Literal, Self, TypeVar
@@ -178,30 +178,3 @@ def find_compatible_wheel(wheels: Sequence[T], identifier: str) -> T | None:
             return wheel
 
     return None
-
-
-def combine_constraints(
-    env: MutableMapping[str, str], /, constraints_path: Path, tmp_dir: Path | None
-) -> None:
-    """
-    This will workaround a bug in pip<=21.1.1 or uv<=0.2.0 if a tmp_dir is given.
-    If set to None, this will use the modern URI method.
-    """
-
-    if tmp_dir:
-        if " " in str(constraints_path):
-            assert " " not in str(tmp_dir)
-            tmp_file = tmp_dir / "constraints.txt"
-            tmp_file.write_bytes(constraints_path.read_bytes())
-            constraints_path = tmp_file
-        our_constraints = str(constraints_path)
-    else:
-        our_constraints = (
-            constraints_path.as_uri() if " " in str(constraints_path) else str(constraints_path)
-        )
-
-    user_constraints = env.get("PIP_CONSTRAINT")
-
-    env["UV_CONSTRAINT"] = env["PIP_CONSTRAINT"] = " ".join(
-        c for c in [our_constraints, user_constraints] if c
-    )

test/test_dependency_versions.py

@@ -1,5 +1,7 @@
+import json
 import platform
 import re
+import subprocess
 import textwrap
 from pathlib import Path
 
@@ -9,40 +11,62 @@
 
 from . import test_projects, utils
 
-project_with_expected_version_checks = test_projects.new_c_project(
-    setup_py_add=textwrap.dedent(
-        r"""
-        import subprocess
-        import os
-        import sys
+VERSION_REGEX = r"([\w-]+)==([^\s]+)"
 
-        versions_output_text = subprocess.check_output(
-            [sys.executable, '-m', 'pip', 'freeze', '--all', '-qq'],
-            universal_newlines=True,
-        )
-        versions = versions_output_text.strip().splitlines()
+CHECK_VERSIONS_SCRIPT = """\
+'''
+Checks that the versions in the env var EXPECTED_VERSIONS match those
+installed in the active venv.
+'''
+import os, subprocess, sys, json
+
+versions_raw = json.loads(
+    subprocess.check_output([
+        sys.executable, '-m', 'pip', 'list', '--format=json',
+    ], text=True)
+)
+versions = {item['name']: item['version'] for item in versions_raw}
+expected_versions = json.loads(os.environ['EXPECTED_VERSIONS'])
+
+for name, expected_version in expected_versions.items():
+    if name not in versions:
+        continue
+    if versions[name] != expected_version:
+        raise SystemExit(f'error: {name} version should equal {expected_version}. Versions: {versions}')
+"""
 
-        # `versions` now looks like:
-        # ['pip==x.x.x', 'setuptools==x.x.x', 'wheel==x.x.x']
 
-        print('Gathered versions', versions)
+def test_check_versions_script(tmp_path, build_frontend_env_nouv, capfd):
+    if utils.get_platform() == "linux":
+        pytest.skip("we don't test dependency versions on linux, refer to other tests")
 
-        expected_version = os.environ['EXPECTED_PIP_VERSION']
+    # sanity check that the CHECK_VERSIONS_SCRIPT fails when it should
+    project_dir = tmp_path / "project"
+    test_projects.new_c_project().generate(project_dir)
 
-        assert f'pip=={expected_version}' in versions, (
-            f'error: pip version should equal {expected_version}'
+    expected_versions = {
+        "pip": "0.0.1",
+        "build": "0.0.2",
+    }
+    script = project_dir / "check_versions.py"
+    script.write_text(CHECK_VERSIONS_SCRIPT)
+
+    with pytest.raises(subprocess.CalledProcessError):
+        utils.cibuildwheel_run(
+            project_dir,
+            add_env={
+                "CIBW_BEFORE_BUILD": f"python {script.name}",
+                "EXPECTED_VERSIONS": json.dumps(expected_versions),
+                **build_frontend_env_nouv,
+            },
         )
-        """
-    )
-)
 
-project_with_expected_version_checks.files["pyproject.toml"] = r"""
-[build-system]
-requires = ["setuptools", "pip"]
-build-backend = "setuptools.build_meta"
-"""
+    captured = capfd.readouterr()
 
-VERSION_REGEX = r"([\w-]+)==([^\s]+)"
+    assert (
+        "error: pip version should equal 0.0.1" in captured.err
+        or "error: build version should equal 0.0.2" in captured.err
+    )
 
 
 def get_versions_from_constraint_file(constraint_file: Path) -> dict[str, str]:
@@ -65,28 +89,29 @@ def test_pinned_versions(tmp_path, python_version, build_frontend_env_nouv):
         pytest.skip(f"Windows ARM64 does not support Python {python_version}")
 
     project_dir = tmp_path / "project"
-    project_with_expected_version_checks.generate(project_dir)
+    test_projects.new_c_project().generate(project_dir)
 
+    # read the expected versions from the appropriate constraint file
     version_no_dot = python_version.replace(".", "")
-    build_environment = {}
-    build_pattern = f"[cp]p{version_no_dot}-*"
+
+    # create cross-platform Python before-build script to verify versions pre-build
+    before_build_script = project_dir / "check_versions.py"
+    before_build_script.write_text(CHECK_VERSIONS_SCRIPT)
+
     if utils.get_platform() == "pyodide":
         constraint_filename = f"constraints-pyodide{version_no_dot}.txt"
     else:
         constraint_filename = f"constraints-python{version_no_dot}.txt"
     constraint_file = resources.PATH / constraint_filename
     constraint_versions = get_versions_from_constraint_file(constraint_file)
 
-    build_environment["EXPECTED_PIP_VERSION"] = constraint_versions["pip"]
-
-    cibw_environment_option = " ".join(f"{k}={v}" for k, v in build_environment.items())
-
-    # build and test the wheels
+    # build and test the wheels (dependency version check occurs before-build)
     actual_wheels = utils.cibuildwheel_run(
         project_dir,
         add_env={
-            "CIBW_BUILD": build_pattern,
-            "CIBW_ENVIRONMENT": cibw_environment_option,
+            "CIBW_BUILD": f"[cp]p{version_no_dot}-*",
+            "CIBW_BEFORE_BUILD": f"python {before_build_script.name}",
+            "EXPECTED_VERSIONS": json.dumps(constraint_versions),
             **build_frontend_env_nouv,
         },
     )
@@ -107,10 +132,11 @@ def test_dependency_constraints(method, tmp_path, build_frontend_env_nouv):
         pytest.skip("linux doesn't pin individual tool versions, it pins manylinux images instead")
 
     project_dir = tmp_path / "project"
-    project_with_expected_version_checks.generate(project_dir)
+    test_projects.new_c_project().generate(project_dir)
 
     tool_versions = {
         "pip": "23.1.2",
+        "build": "1.2.2",
         "delocate": "0.10.3",
     }
 
@@ -120,6 +146,7 @@ def test_dependency_constraints(method, tmp_path, build_frontend_env_nouv):
             textwrap.dedent(
                 """
                 pip=={pip}
+                build=={build}
                 delocate=={delocate}
                 """.format(**tool_versions)
             )
@@ -133,7 +160,7 @@ def test_dependency_constraints(method, tmp_path, build_frontend_env_nouv):
         msg = f"Unknown method: {method}"
         raise ValueError(msg)
 
-    build_environment = {}
+    skip = ""
 
     if (
         utils.get_platform() == "windows"
@@ -144,32 +171,29 @@ def test_dependency_constraints(method, tmp_path, build_frontend_env_nouv):
         # from a virtualenv seeded executable. See
         # https://github.com/oracle/graalpython/issues/491 and remove this once
         # fixed upstream.
-        build_frontend_env_nouv["CIBW_SKIP"] = "gp*"
-
-    for package_name, version in tool_versions.items():
-        env_name = f"EXPECTED_{package_name.upper()}_VERSION"
-        build_environment[env_name] = version
+        skip = "gp*"
 
-    cibw_environment_option = " ".join(f"{k}={v}" for k, v in build_environment.items())
+    # cross-platform Python script for dependency constraint checks
+    before_build_script = project_dir / "check_versions.py"
+    before_build_script.write_text(CHECK_VERSIONS_SCRIPT)
 
-    # build and test the wheels
+    # build and test the wheels (dependency version check occurs pre-build)
     actual_wheels = utils.cibuildwheel_run(
         project_dir,
         add_env={
-            "CIBW_ENVIRONMENT": cibw_environment_option,
+            "CIBW_SKIP": skip,
             "CIBW_DEPENDENCY_VERSIONS": dependency_version_option,
+            "CIBW_BEFORE_BUILD": f"python {before_build_script.name}",
+            "EXPECTED_VERSIONS": json.dumps(tool_versions),
             **build_frontend_env_nouv,
         },
+        single_python=True,
     )
 
     # also check that we got the right wheels
-    expected_wheels = utils.expected_wheels("spam", "0.1.0")
+    expected_wheels = utils.expected_wheels("spam", "0.1.0", single_python=True)
 
-    if (
-        utils.get_platform() == "windows"
-        and method == "file"
-        and build_frontend_env_nouv["CIBW_BUILD_FRONTEND"] == "build"
-    ):
+    if skip == "gp*":
         # See reference to https://github.com/oracle/graalpython/issues/491
         # above
         expected_wheels = [w for w in expected_wheels if "graalpy" not in w]