skip get_requires for setuptools projects

.pre-commit-config.yaml

@@ -1,5 +1,10 @@
 # Copyright (c) 2024, NVIDIA CORPORATION.
 
+exclude: |
+  (?x)^(
+      tests/templates/.*py
+  )$
+
 repos:
   - repo: https://github.com/pre-commit/pre-commit-hooks
     rev: v4.6.0

README.md

@@ -29,6 +29,28 @@ Any option without a default is required.
 
 - How should we split up build requirements between `build-system` and `tool.rapids-build-backend`? In theory any dependency that doesn't need suffixing could also go into `build-system.requires`. I think it's easier to teach that all dependencies other than `rapids-build-backend` itself should to into `tool.rapids-build-backend`, but I don't know how others feel.
 
+## `setuptools` support
+
+This project supports builds using `setuptools.build_meta` as their build backend, and which use a `setup.py` for configuration.
+
+However, it does not support passing a list of dependencies through `setup_requires` to `setuptools.setup()`.
+If you're interested in using `setuptools.build_meta` and a `setup.py`, pass a list of dependencies that need to be installed prior to `setup.py` running through `rapids-build-backend`'s requirements, like this:
+
+```toml
+[project]
+build-backend = "rapids_build_backend.build"
+requires = [
+    "rapids-build-backend",
+    "setuptools"
+]
+
+[tool.rapids-build-backend]
+build-backend = "setuptools.build_meta"
+requires = [
+    "Cython"
+]
+```
+
 ## Rejected ideas
 
 - We could also include the rewrite of VERSION that we use for RAPIDS builds, but this is really more specific to our release process than the general process of building our wheels. I don't think someone building a wheel locally should see the same version as what we produce via CI. If we really wanted we could pull dunamai as a dependency and write a different version here, though.

ci/check_style.sh

@@ -10,7 +10,7 @@ ENV_YAML_DIR="$(mktemp -d)"
 
 rapids-dependency-file-generator \
   --output conda \
-  --file_key checks \
+  --file-key checks \
   --matrix "cuda=${RAPIDS_CUDA_VERSION%.*};arch=$(arch);py=${RAPIDS_PY_VERSION}" | tee "${ENV_YAML_DIR}/env.yaml"
 
 rapids-mamba-retry env create --yes -f "${ENV_YAML_DIR}/env.yaml" -n checks

rapids_build_backend/impls.py

@@ -210,6 +210,35 @@ def _edit_pyproject(config):
         shutil.move(bkp_pyproject_file, pyproject_file)
 
 
+def _check_setup_py(setup_py_contents: str) -> None:
+    """
+    ``setuptools.get_requires_for_build_wheel()`` executes setup.py if it exists,
+    to check for dependencies in ``setup_requires`` (passed to ``setuptools.setup()``).
+
+    That's a problem for rapids-build-backend, as at the point where that's invoked,
+    its recalculated list of build dependencies (modified in ``_edit_pyproject()``)
+    haven't yet been installed.
+
+    If any of them are imported in ``setup.py``, those imports will fail.
+
+    This function raises an exception if it detects ``setup_requires`` being used in
+    a ``setup.py``, to clarify that ``rapids-build-backend`` can't support that case.
+
+    ref: https://github.com/rapidsai/rapids-build-backend/issues/39
+    """
+
+    # pattern = "any use of 'setup_requires' on a line that isn't a comment"
+    setup_requires_pat = r"^(?!\s*#+).*setup_requires"
+
+    if re.search(setup_requires_pat, setup_py_contents, re.M) is not None:
+        raise ValueError(
+            "Detected use of 'setup_requires' in a setup.py file. "
+            "rapids-build-backend does not support this pattern. Try moving "
+            "that list of dependencies into the 'requires' list in the "
+            "[tool.rapids-build-backend] table in pyproject.toml."
+        )
+
+
 # The hooks in this file could be defined more programmatically by iterating over the
 # backend's attributes, but it's simpler to just define them explicitly and avoids any
 # potential issues with assuming the right pyproject.toml is readable at import time (we
@@ -234,11 +263,23 @@ def get_requires_for_build_wheel(config_settings):
             backend := _get_backend(config.build_backend),
             "get_requires_for_build_wheel",
         ):
-            requires.extend(
-                backend.get_requires_for_build_wheel(
-                    _remove_rapidsai_from_config(config_settings)
+            if config.build_backend == "setuptools.build_meta":
+                _check_setup_py(setup_py_contents=utils._get_setup_py())
+                # prior to https://github.com/pypa/setuptools/pull/4369 (May 2024),
+                # setuptools.build_meta.get_requires_for_build_wheel() automatically
+                # added 'wheel' to the build requirements. Adding that manually here,
+                # since this code block skips running
+                # setuptools.build_meta.get_requires_for_build_wheel().
+                #
+                # Without this, running 'pip wheel' might result in an error like
+                # "error: invalid command 'bdist_wheel'".
+                requires.extend(["wheel"])
+            else:
+                requires.extend(
+                    backend.get_requires_for_build_wheel(
+                        _remove_rapidsai_from_config(config_settings)
+                    )
                 )
-            )
 
         return requires
 
@@ -256,11 +297,14 @@ def get_requires_for_build_sdist(config_settings):
             backend := _get_backend(config.build_backend),
             "get_requires_for_build_sdist",
         ):
-            requires.extend(
-                backend.get_requires_for_build_sdist(
-                    _remove_rapidsai_from_config(config_settings)
+            if config.build_backend == "setuptools.build_meta":
+                _check_setup_py(setup_py_contents=utils._get_setup_py())
+            else:
+                requires.extend(
+                    backend.get_requires_for_build_sdist(
+                        _remove_rapidsai_from_config(config_settings)
+                    )
                 )
-            )
 
         return requires
 
@@ -276,11 +320,14 @@ def get_requires_for_build_editable(config_settings):
             backend := _get_backend(config.build_backend),
             "get_requires_for_build_editable",
         ):
-            requires.extend(
-                backend.get_requires_for_build_editable(
-                    _remove_rapidsai_from_config(config_settings)
+            if config.build_backend == "setuptools.build_meta":
+                _check_setup_py(setup_py_contents=utils._get_setup_py())
+            else:
+                requires.extend(
+                    backend.get_requires_for_build_editable(
+                        _remove_rapidsai_from_config(config_settings)
+                    )
                 )
-            )
 
         return requires
 

rapids_build_backend/utils.py

@@ -9,3 +9,21 @@ def _get_pyproject(dirname: str = ".") -> tomlkit.toml_document.TOMLDocument:
     """Parse and return the pyproject.toml file."""
     with open(os.path.join(dirname, "pyproject.toml")) as f:
         return tomlkit.load(f)
+
+
+def _get_setup_py() -> str:
+    """
+    Returns a string with the contents of setup.py,
+    or empty string if it doesn't exist.
+    """
+    # setuptools.build_meta.get_requires_for_wheel() assumes that "setup.py" is directly
+    # relative to the current working directly, so rapids-build-backend can too.
+    #
+    # ref: https://github.com/pypa/setuptools/blob/f91fa3d9fc7262e0467e4b2f84fe463f8f8d23cf/setuptools/build_meta.py#L304
+    setup_py_file = "setup.py"
+
+    if not os.path.isfile(setup_py_file):
+        return ""
+
+    with open(setup_py_file) as f:
+        return f.read()

tests/templates/dependencies-rbb-only.yaml

@@ -0,0 +1,32 @@
+# Copyright (c) 2024, NVIDIA CORPORATION.
+
+# [description]
+#
+#   dependencies.yaml that intentionally only updates [tool.rapids-build-backend] table
+#   in pyproject.toml.
+#
+#   Create new templates to test other dependencies.yaml contents.
+#
+
+files:
+  py_rapids_build:
+    output: pyproject
+    pyproject_dir: .
+    extras:
+      table: tool.rapids-build-backend
+      key: requires
+    includes:
+      - build_python
+dependencies:
+  build_python:
+    specific:
+      - output_types: [pyproject, requirements]
+        matrices:
+          - matrix: {cuda: "85.*"}
+            packages:
+              - more-itertools
+          # keeping this empty means it'll only be filled in if
+          # rapids-build-backend actually resolves one of the CUDA-specific
+          # matrices
+          - matrix: null
+            packages: null

tests/templates/setup.py

@@ -0,0 +1,5 @@
+from setuptools import setup
+
+{% for line in setup_py_lines %}
+{{ line }}
+{% endfor %}

tests/test_impls.py

@@ -8,6 +8,7 @@
 import pytest
 
 from rapids_build_backend.impls import (
+    _check_setup_py,
     _edit_pyproject,
     _get_cuda_suffix,
     _remove_rapidsai_from_config,
@@ -322,3 +323,58 @@ def test_edit_pyproject(
 
         with open("pyproject.toml") as f:
             assert f.read() == original_contents
+
+
+@pytest.mark.parametrize(
+    ("setup_py_content",),
+    [
+        # empty
+        ("",),
+        # 'setup_requires' in a comment on its own line
+        (
+            """
+            from setuptools import setup
+            # setup_requires
+            setup()
+            """,
+        ),
+    ],
+)
+def test_check_setup_py_works_when_setup_requires_not_passed(setup_py_content):
+    assert _check_setup_py(setup_py_content) is None
+
+
+@pytest.mark.parametrize(
+    ("setup_py_content",),
+    [
+        # 'setup_requires' actually passed into setup(), on the same line
+        (
+            """
+            from setuptools import setup
+            setup(setup_requires=[])
+            """,
+        ),
+        # 'setup_requires' actually passed into setup(), on its own line
+        (
+            """
+            from setuptools import setup
+            setup(
+                setup_requires=['rmm']
+            )
+            """,
+        ),
+        # 'setup_requires' actually passed into setup(), via a dictionary
+        (
+            """
+            from setuptools import setup
+            opts = {'setup_requires': ['rmm']}
+            setup(**opts)
+            """,
+        ),
+    ],
+)
+def test_check_setup_py_fails_when_setup_requires_is_passed(setup_py_content):
+    with pytest.raises(
+        ValueError, match=r"Detected use of 'setup_requires' in a setup\.py file"
+    ):
+        _check_setup_py(setup_py_content)