feat: option to build directly with uv (#2322)

* feat: option to build directly with uv

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

tests: add uv to tests

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

fix: uv doesn't pick special Pythons at the top of the path

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

fix: set uv build constraints too

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

fix: uv doesn't support PyPy 3.8

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

tests: add pyproject.toml for failing test

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

Revert "tests: add pyproject.toml for failing test"

This reverts commit 619bde368a67dfdd8f02dc33a1525c27bc8cbe91.

tests: skip uv output test

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

* tests: uv was in the wrong fixture

Signed-off-by: Henry Schreiner <henryfs@princeton.edu>

* fix: from @trim21

Signed-off-by: Henry Schreiner <henryfs@princeton.edu>

* tests: improve skipping

Signed-off-by: Henry Schreiner <henryfs@princeton.edu>

* fix: some fixes from copilot review

Signed-off-by: Henry Schreiner <henryfs@princeton.edu>

---------

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

bin/generate_schema.py

@@ -57,21 +57,23 @@ properties:
     type: string_array
   build-frontend:
     default: default
-    description: Set the tool to use to build, either "build" (default), "build[uv]", or "pip"
+    description: Set the tool to use to build, either "build" (default), "build[uv]", "uv", or "pip"
     oneOf:
-      - enum: [pip, build, "build[uv]", default]
+      - enum: [pip, build, "build[uv]", uv, default]
       - type: string
         pattern: '^pip; ?args:'
       - type: string
         pattern: '^build; ?args:'
       - type: string
         pattern: '^build\\[uv\\]; ?args:'
+      - type: string
+        pattern: '^uv; ?args:'
       - type: object
         additionalProperties: false
         required: [name]
         properties:
           name:
-            enum: [pip, build, "build[uv]"]
+            enum: [pip, build, "build[uv]", uv]
           args:
             type: array
             items:

cibuildwheel/frontend.py

@@ -7,7 +7,7 @@ from typing import Literal, Self, get_args
 from .logger import log
 from .util.helpers import parse_key_value_string
 
-BuildFrontendName = Literal["pip", "build", "build[uv]"]
+BuildFrontendName = Literal["pip", "build", "build[uv]", "uv"]
 
 
 @dataclasses.dataclass(frozen=True)

cibuildwheel/platforms/ios.py

@@ -284,7 +284,7 @@ def setup_python(
     build_frontend: BuildFrontendName,
     xbuild_tools: Sequence[str] | None,
 ) -> tuple[Path, dict[str, str]]:
-    if build_frontend == "build[uv]":
+    if build_frontend == "build[uv]" or build_frontend == "uv":
         msg = "uv doesn't support iOS"
         raise errors.FatalError(msg)
 
@@ -441,7 +441,7 @@ def build(options: Options, tmp_path: Path) -> None:
             build_options = options.build_options(config.identifier)
             build_frontend = build_options.build_frontend
             # uv doesn't support iOS
-            if build_frontend.name == "build[uv]":
+            if build_frontend.name == "build[uv]" or build_frontend.name == "uv":
                 msg = "uv doesn't support iOS"
                 raise errors.FatalError(msg)
 

cibuildwheel/platforms/linux.py

@@ -207,7 +207,7 @@ def build_in_container(
         local_identifier_tmp_dir = local_tmp_dir / config.identifier
         build_options = options.build_options(config.identifier)
         build_frontend = build_options.build_frontend
-        use_uv = build_frontend.name == "build[uv]"
+        use_uv = build_frontend.name in {"build[uv]", "uv"}
         pip = ["uv", "pip"] if use_uv else ["pip"]
 
         log.step("Setting up build environment...")
@@ -307,6 +307,19 @@ def build_in_container(
                         ],
                         env=env,
                     )
+                case "uv":
+                    container.call(
+                        [
+                            "uv",
+                            "build",
+                            "--python=python",
+                            container_package_dir,
+                            "--wheel",
+                            f"--out-dir={built_wheel_dir}",
+                            *extra_flags,
+                        ],
+                        env=env,
+                    )
                 case _:
                     assert_never(build_frontend)
 
@@ -509,6 +522,7 @@ def _matches_prepared_command(error_cmd: Sequence[str], command_template: str) -
 def troubleshoot(options: Options, error: Exception) -> None:
     if isinstance(error, subprocess.CalledProcessError) and (
         error.cmd[0:4] == ["python", "-m", "pip", "wheel"]
+        or error.cmd[0:2] == ["uv", "build"]
         or error.cmd[0:3] == ["python", "-m", "build"]
         or _matches_prepared_command(
             error.cmd, options.build_options(None).repair_command

cibuildwheel/platforms/macos.py

@@ -218,7 +218,7 @@ def setup_python(
     build_frontend: BuildFrontendName,
 ) -> tuple[Path, dict[str, str]]:
     uv_path = find_uv()
-    use_uv = build_frontend == "build[uv]"
+    use_uv = build_frontend in {"build[uv]", "uv"}
 
     tmp.mkdir()
     implementation_id = python_configuration.identifier.split("-")[0]
@@ -381,6 +381,17 @@ def setup_python(
                 *constraint_flags(dependency_constraint),
                 env=env,
             )
+        case "uv":
+            assert uv_path is not None
+            call(
+                uv_path,
+                "pip",
+                "install",
+                "--upgrade",
+                "delocate",
+                *constraint_flags(dependency_constraint),
+                env=env,
+            )
         case _:
             assert_never(build_frontend)
 
@@ -413,7 +424,7 @@ def build(options: Options, tmp_path: Path) -> None:
         for config in python_configurations:
             build_options = options.build_options(config.identifier)
             build_frontend = build_options.build_frontend
-            use_uv = build_frontend.name == "build[uv]"
+            use_uv = build_frontend.name in {"build[uv]", "uv"}
             uv_path = find_uv()
             if use_uv and uv_path is None:
                 msg = "uv not found"
@@ -498,6 +509,18 @@ def build(options: Options, tmp_path: Path) -> None:
                             *extra_flags,
                             env=build_env,
                         )
+                    case "uv":
+                        assert uv_path is not None
+                        call(
+                            uv_path,
+                            "build",
+                            "--python=python",
+                            build_options.package_dir,
+                            "--wheel",
+                            f"--out-dir={built_wheel_dir}",
+                            *extra_flags,
+                            env=build_env,
+                        )
                     case _:
                         assert_never(build_frontend)
 

cibuildwheel/platforms/windows.py

@@ -271,7 +271,7 @@ def setup_python(
     if build_frontend == "build[uv]" and not can_use_uv(python_configuration):
         build_frontend = "build"
 
-    use_uv = build_frontend == "build[uv]"
+    use_uv = build_frontend in {"build[uv]", "uv"}
     uv_path = find_uv()
 
     log.step("Setting up build environment...")
@@ -386,6 +386,8 @@ def build(options: Options, tmp_path: Path) -> None:
     if not python_configurations:
         return
 
+    uv_path = find_uv()
+
     try:
         before_all_options_identifier = python_configurations[0].identifier
         before_all_options = options.build_options(before_all_options_identifier)
@@ -403,8 +405,7 @@ def build(options: Options, tmp_path: Path) -> None:
         for config in python_configurations:
             build_options = options.build_options(config.identifier)
             build_frontend = build_options.build_frontend
-
+            use_uv = build_frontend.name in {"build[uv]", "uv"} and can_use_uv(config)
-            use_uv = build_frontend.name == "build[uv]" and can_use_uv(config)
             log.build_start(config.identifier)
 
             identifier_tmp_dir = tmp_path / config.identifier
@@ -501,6 +502,18 @@ def build(options: Options, tmp_path: Path) -> None:
                             *extra_flags,
                             env=env,
                         )
+                    case "uv":
+                        assert uv_path is not None
+                        call(
+                            uv_path,
+                            "build",
+                            "--python=python",
+                            build_options.package_dir,
+                            "--wheel",
+                            f"--out-dir={built_wheel_dir}",
+                            *extra_flags,
+                            env=env,
+                        )
                     case _:
                         assert_never(build_frontend)
 

test/conftest.py

@@ -163,7 +163,7 @@ def build_frontend_env_nouv(request: pytest.FixtureRequest) -> dict[str, str]:
     return {"CIBW_BUILD_FRONTEND": frontend}
 
 
-@pytest.fixture(params=["pip", "build", "build[uv]"])
+@pytest.fixture(params=["pip", "build", "build[uv]", "uv"])
 def build_frontend_env(request: pytest.FixtureRequest) -> dict[str, str]:
     frontend = request.param
     marks = {m.name for m in request.node.iter_markers()}
@@ -178,10 +178,12 @@ def build_frontend_env(request: pytest.FixtureRequest) -> dict[str, str]:
 
     if platform in {"pyodide", "ios", "android"} and frontend == "pip":
         pytest.skip(f"Can't use pip as build frontend for {platform}")
-    if platform == "pyodide" and frontend == "build[uv]":
+    if platform == "android" and frontend == "uv":
+        pytest.skip(f"Can't use uv as build frontend for {platform}")
+    if platform == "pyodide" and frontend in {"build[uv]", "uv"}:
         pytest.skip("Can't use uv with pyodide yet")
     uv_path = find_uv()
-    if uv_path is None and frontend == "build[uv]":
+    if uv_path is None and frontend in {"build[uv]", "uv"}:
         pytest.skip("Can't find uv, so skipping uv tests")
     if uv_path is not None and frontend == "build" and platform not in {"android", "ios"}:
         pytest.skip("No need to check build when uv is present")

test/test_android.py

@@ -128,7 +128,7 @@ def test_frontend_good(tmp_path, build_frontend_env):
     assert wheels == [f"spam-0.1.0-cp313-cp313-android_21_{native_arch.android_abi}.whl"]
 
 
-@pytest.mark.parametrize("frontend", ["pip"])
+@pytest.mark.parametrize("frontend", ["pip", "uv"])
 def test_frontend_bad(frontend, tmp_path, capfd):
     new_c_project().generate(tmp_path)
     with pytest.raises(CalledProcessError):

unit_test/options_test.py

@@ -328,6 +328,11 @@ def test_environment_pass_references():
             "build",
             [],
         ),
+        (
+            'build-frontend = "uv"',
+            "uv",
+            [],
+        ),
         (
             'build-frontend = {name = "build"}',
             "build",