Fix 1216 explicitly deprecate setuptools dynamic version when active

.github/workflows/api-check.yml

@@ -32,22 +32,48 @@ jobs:
         run: |
           pip install -U pip setuptools
           pip install -e .[test]
+          pip install griffe
 
       - name: Run griffe API check
         id: griffe-check
+        continue-on-error: true
         run: |
+          echo "Running griffe API stability check..."
           if griffe check setuptools_scm -ssrc -f github; then
             echo "api_check_result=success" >> $GITHUB_OUTPUT
+            echo "exit_code=0" >> $GITHUB_OUTPUT
           else
+            exit_code=$?
             echo "api_check_result=warning" >> $GITHUB_OUTPUT
-            echo "API stability check detected changes but will not fail the build" >> $GITHUB_STEP_SUMMARY
+            echo "exit_code=$exit_code" >> $GITHUB_OUTPUT
+            exit $exit_code
           fi
 
       - name: Report API check result
-        if: steps.griffe-check.outputs.api_check_result == 'warning'
+        if: always()
         uses: actions/github-script@v8
         with:
           script: |
-            core.warning('API stability check detected breaking changes. Please review the API changes above.')
-            core.summary.addRaw('⚠️ API Stability Warning: Breaking changes detected in the public API')
-            await core.summary.write()
+            const result = '${{ steps.griffe-check.outputs.api_check_result }}'
+            const exitCode = '${{ steps.griffe-check.outputs.exit_code }}'
+
+            if (result === 'success') {
+              core.notice('API stability check passed - no breaking changes detected')
+              await core.summary
+                .addHeading('✅ API Stability Check: Passed', 2)
+                .addRaw('No breaking changes detected in the public API')
+                .write()
+            } else if (result === 'warning') {
+              core.warning(`API stability check detected breaking changes (exit code: ${exitCode}). Please review the API changes above.`)
+              await core.summary
+                .addHeading('⚠️ API Stability Warning', 2)
+                .addRaw('Breaking changes detected in the public API. Please review the changes reported above.')
+                .addRaw(`\n\nExit code: ${exitCode}`)
+                .write()
+            } else {
+              core.error('API stability check failed to run properly')
+              await core.summary
+                .addHeading('❌ API Stability Check: Failed', 2)
+                .addRaw('The griffe check failed to execute. This may indicate griffe is not installed or there was an error.')
+                .write()
+            }

.github/workflows/python-tests.yml

@@ -68,7 +68,7 @@ jobs:
           msystem: MINGW64
           install: git mingw-w64-x86_64-python mingw-w64-x86_64-python-setuptools
           update: true
-      - name: Setup GnuPG
+      - name: Setup GnuPG and Mercurial on Windows
         # At present, the Windows VMs only come with the copy of GnuPG that's bundled
         # with Git for Windows. If we want to use this version _and_ be able to set
         # arbitrary GnuPG home directories, then the test would need to figure out when
@@ -84,11 +84,15 @@ jobs:
         # Additionally, we'll explicitly set `gpg.program` to ensure Git for Windows
         # doesn't invoke the bundled GnuPG, otherwise we'll run into
         # <https://dev.gnupg.org/T5504>. See also: <https://dev.gnupg.org/T3020>.
+        #
+        # Windows runners no longer ship with Mercurial pre-installed, so we install
+        # it via Chocolatey using the 'hg' package.
         run: |
           $env:PATH = "C:\Program Files\Git\bin;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\ProgramData\Chocolatey\bin"
           [Environment]::SetEnvironmentVariable("Path", $env:PATH, "Machine")
-          choco install gnupg -y --no-progress
+          choco install gnupg hg -y --no-progress
           echo "C:\Program Files (x86)\gnupg\bin" >> $env:GITHUB_PATH
+          echo "C:\Program Files\Mercurial\" >> $env:GITHUB_PATH
           git config --system gpg.program "C:\Program Files (x86)\gnupg\bin\gpg.exe"
         if: runner.os == 'Windows'
       - run: uv sync --group test --group docs --extra rich

.pre-commit-config.yaml

@@ -18,7 +18,6 @@ repos:
     hooks:
     -   id: mypy
         args: [--strict]
-        language_version: "3.10"
         additional_dependencies:
             - types-setuptools
             - tokenize-rt==3.2.0

CHANGELOG.md

@@ -1,5 +1,14 @@
 # Changelog
 
+
+## v9.2.1 (unreleased)
+
+### 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
@@ -11,24 +20,24 @@
   version inference is automatically enabled with default settings.
 
 
-### removed
+### Removed
 
 - unchecked simplified activation - too many projects use setups where it would fail
 
-### changed
+### Changed
 
 - refine activation logic and add unittest for the relevant cases instead of trying to speedrun setuptools
 
 ## v9.1.1 (yanked)
 
-### fixed
+### Fixed
 
 - fix #1194: correctly handle version keyword when pyproject metadata is missing
 
 
 ## v9.1.0 (yanked)
 
-### fixed
+### Fixed
 
 - complete reiteration of the decision logic for enabling version inference on setuptools_scm
 
@@ -40,9 +49,9 @@
 
 ## v9.0.3 (yanked)
 
-### fixed
+### Fixed
 
-- fix 1184: verify version is dynamic if the dependency is used as indicator for enabling
+- fix #1184: verify version is dynamic if the dependency is used as indicator for enabling
 
 ## v9.0.2 (yanked)
 

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} is forcing setuptools to override the version setuptools-scm did already set\n"
+        "When using setuptools-scm it's invalid to use setuptools dynamic version as well, please remove it.\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

@@ -174,19 +174,23 @@ 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.
 
-    This function supports dependency injection for tests via `_given_result`.
-
-    Parameters:
-    - path: Path to the pyproject file
-    - tool_name: The tool section name (default: `setuptools_scm`)
-    - canonical_build_package_name: Normalized build requirement name
-    - _given_result: Optional testing hook. Can be:
-        - PyProjectData: returned directly
-        - InvalidTomlError | FileNotFoundError: raised directly
-        - None: read from filesystem
+    This function supports dependency injection for tests via ``_given_result``
+    and ``_given_definition``.
+
+    :param path: Path to the pyproject file
+    :param tool_name: The tool section name (default: ``setuptools_scm``)
+    :param canonical_build_package_name: Normalized build requirement name
+    :param _given_result: Optional testing hook. Can be:
+        - ``PyProjectData``: returned directly
+        - ``InvalidTomlError`` | ``FileNotFoundError``: raised directly
+        - ``None``: read from filesystem (default)
+    :param _given_definition: Optional testing hook to provide parsed TOML content.
+        When provided, this dictionary is used instead of reading and parsing
+        the file from disk. Ignored if ``_given_result`` is provided.
     """
 
     if _given_result is not None:
@@ -195,7 +199,10 @@ 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 +231,17 @@ 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 is forcing setuptools to override the version setuptools-scm did already set\n"
+        "When using setuptools-scm it's invalid to use setuptools dynamic version as well, please remove it.\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