Fix 1216 explicitly deprecate setuptools dynamic version when active

CHANGELOG.md

@@ -1,5 +1,14 @@
 # Changelog
 
+
+## v9.2.0
+
+### fixed
+
+- fix #1216: accept and create a warning for usages of `version = attr:` in setuptools config.
+  unfortunately dozens of projects cargo-culted that antipattern
+
+
 ## v9.2.0
 
 ### Added

src/setuptools_scm/_config.py

@@ -310,7 +310,6 @@ def from_data(
         # Handle nested SCM configuration
 
         scm_config = ScmConfiguration.from_data(scm_data)
-
         return cls(
             relative_to=relative_to,
             version_cls=version_cls,

src/setuptools_scm/_integration/deprecation.py

@@ -0,0 +1,20 @@
+import warnings
+
+from pathlib import Path
+
+
+def warn_dynamic_version(path: Path, section: str, expression: str) -> None:
+    warnings.warn(
+        f"{path}: at [{section}]\n"
+        f"{expression} forcing setuptools to override the version setuptools-scm sets\n"
+        "When using setuptools-scm its invalid to use setuptools dynamic version as well, please removeit.\n"
+        "Setuptools-scm is responsible for setting the version, forcing setuptools to override creates errors."
+    )
+
+
+def warn_pyproject_setuptools_dynamic_version(path: Path) -> None:
+    warn_dynamic_version(path, "tool.setuptools.dynamic", "version = {attr = ...}")
+
+
+def warn_setup_cfg_dynamic_version(path: Path) -> None:
+    warn_dynamic_version(path, "metadata", "version = attr: ...}")

src/setuptools_scm/_integration/pyproject_reading.py

@@ -174,6 +174,7 @@ def read_pyproject(
     tool_name: str = DEFAULT_TOOL_NAME,
     canonical_build_package_name: str = "setuptools-scm",
     _given_result: _t.GivenPyProjectResult = None,
+    _given_definition: TOML_RESULT | None = None,
 ) -> PyProjectData:
     """Read and parse pyproject configuration.
 
@@ -195,7 +196,10 @@ def read_pyproject(
         if isinstance(_given_result, (InvalidTomlError, FileNotFoundError)):
             raise _given_result
 
-    defn = read_toml_content(path)
+    if _given_definition is not None:
+        defn = _given_definition
+    else:
+        defn = read_toml_content(path)
 
     requires: list[str] = defn.get("build-system", {}).get("requires", [])
     is_required = has_build_package(requires, canonical_build_package_name)
@@ -224,6 +228,17 @@ def read_pyproject(
         requires,
     )
 
+    setuptools_dynamic_version = (
+        defn.get("tool", {})
+        .get("setuptools", {})
+        .get("dynamic", {})
+        .get("version", None)
+    )
+    if setuptools_dynamic_version is not None:
+        from .deprecation import warn_pyproject_setuptools_dynamic_version
+
+        warn_pyproject_setuptools_dynamic_version(path)
+
     return pyproject_data
 
 

src/setuptools_scm/_integration/setup_cfg.py

@@ -25,6 +25,11 @@ def read_setup_cfg(input: str | os.PathLike[str] = "setup.cfg") -> SetuptoolsBas
 
     name = parser.get("metadata", "name", fallback=None)
     version = parser.get("metadata", "version", fallback=None)
+    if version is not None and "attr" in version:
+        from .deprecation import warn_setup_cfg_dynamic_version
+
+        warn_setup_cfg_dynamic_version(path)
+        version = None
     return SetuptoolsBasicData(path=path, name=name, version=version)
 
 

testing/test_deprecation.py

@@ -0,0 +1,24 @@
+"""Test deprecation warnings and their exact text."""
+
+from pathlib import Path
+
+import pytest
+
+from setuptools_scm._integration.deprecation import warn_dynamic_version
+
+
+def test_warn_dynamic_version_full_text() -> None:
+    """Test the complete warning text for warn_dynamic_version function."""
+    test_path = Path("test_file.toml")
+    expected_warning = (
+        f"{test_path}: at [test.section]\n"
+        "test_expression forcing setuptools to override the version setuptools-scm sets\n"
+        "When using setuptools-scm its invalid to use setuptools dynamic version as well, please removeit.\n"
+        "Setuptools-scm is responsible for setting the version, forcing setuptools to override creates errors."
+    )
+
+    with pytest.warns(UserWarning) as warning_info:  # noqa: PT030
+        warn_dynamic_version(test_path, "test.section", "test_expression")
+
+    assert len(warning_info) == 1
+    assert str(warning_info[0].message) == expected_warning

testing/test_integration.py

@@ -18,6 +18,7 @@
 from setuptools_scm._integration import setuptools as setuptools_integration
 from setuptools_scm._integration.pyproject_reading import PyProjectData
 from setuptools_scm._integration.setup_cfg import SetuptoolsBasicData
+from setuptools_scm._integration.setup_cfg import read_setup_cfg
 from setuptools_scm._requirement_cls import extract_package_name
 
 if TYPE_CHECKING:
@@ -457,6 +458,29 @@ def test_unicode_in_setup_cfg(tmp_path: Path) -> None:
     assert data.version == "1.2.3"
 
 
+@pytest.mark.issue(1216)
+def test_setup_cfg_dynamic_version_warns_and_ignores(tmp_path: Path) -> None:
+    cfg = tmp_path / "setup.cfg"
+    cfg.write_text(
+        textwrap.dedent(
+            """
+            [metadata]
+            name = example-broken
+            version = attr: example_broken.__version__
+            """
+        ),
+        encoding="utf-8",
+    )
+
+    with pytest.warns(
+        UserWarning,
+        match=r"setup\.cfg: at \[metadata\]",
+    ):
+        legacy_data = read_setup_cfg(cfg)
+
+    assert legacy_data.version is None
+
+
 def test_setup_cfg_version_prevents_inference_version_keyword(
     tmp_path: Path, monkeypatch: pytest.MonkeyPatch
 ) -> None:

testing/test_pyproject_reading.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 from pathlib import Path
+from unittest.mock import Mock
 
 import pytest
 
@@ -108,3 +109,39 @@ def test_invalid_requirement_string(self) -> None:
         assert (
             has_build_package_with_extra(requires, "setuptools-scm", "simple") is False
         )
+
+
+def test_read_pyproject_with_given_definition(monkeypatch: pytest.MonkeyPatch) -> None:
+    """Test that read_pyproject reads existing files correctly."""
+    monkeypatch.setattr(
+        "setuptools_scm._integration.pyproject_reading.read_toml_content",
+        Mock(side_effect=FileNotFoundError("this test should not read")),
+    )
+
+    res = read_pyproject(
+        _given_definition={
+            "build-system": {"requires": ["setuptools-scm[simple]"]},
+            "project": {"name": "test-package", "dynamic": ["version"]},
+        }
+    )
+
+    assert res.should_infer()
+
+
+def test_read_pyproject_with_setuptools_dynamic_version_warns() -> None:
+    with pytest.warns(
+        UserWarning,
+        match=r"pyproject\.toml: at \[tool\.setuptools\.dynamic\]",
+    ):
+        pyproject_data = read_pyproject(
+            _given_definition={
+                "build-system": {"requires": ["setuptools-scm[simple]"]},
+                "project": {"name": "test-package", "dynamic": ["version"]},
+                "tool": {
+                    "setuptools": {
+                        "dynamic": {"version": {"attr": "test_package.__version__"}}
+                    }
+                },
+            }
+        )
+    assert pyproject_data.project_version is None