use a actually user friendly deprecation for the setuptools dynamic antipattern

Author: RonnyPfannschmidt

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

@@ -235,10 +235,9 @@ def read_pyproject(
         .get("version", None)
     )
     if setuptools_dynamic_version is not None:
-        warnings.warn(
-            f"{path}: at [tool.setuptools.dynamic]\n"
-            "version = {attr = ...} is sabotaging setuptools-scm"
-        )
+        from .deprecation import warn_pyproject_setuptools_dynamic_version
+
+        warn_pyproject_setuptools_dynamic_version(path)
 
     return pyproject_data
 

src/setuptools_scm/_integration/setup_cfg.py

@@ -1,7 +1,6 @@
 from __future__ import annotations
 
 import os
-import warnings
 
 from dataclasses import dataclass
 from pathlib import Path
@@ -27,10 +26,9 @@ 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:
-        warnings.warn(
-            "setup.cfg: ignoring invalid dynamic version - version = attr: ..."
-            " is sabotaging setuptools-scm"
-        )
+        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

@@ -474,7 +474,7 @@ def test_setup_cfg_dynamic_version_warns_and_ignores(tmp_path: Path) -> None:
 
     with pytest.warns(
         UserWarning,
-        match="setup.cfg: ignoring invalid dynamic version - version = attr: ... is sabotaging setuptools-scm",
+        match=r"setup\.cfg: at \[metadata\]",
     ):
         legacy_data = read_setup_cfg(cfg)
 

testing/test_pyproject_reading.py

@@ -131,8 +131,7 @@ def test_read_pyproject_with_given_definition(monkeypatch: pytest.MonkeyPatch) -
 def test_read_pyproject_with_setuptools_dynamic_version_warns() -> None:
     with pytest.warns(
         UserWarning,
-        match=r"pyproject.toml: at \[tool\.setuptools\.dynamic\]\n"
-        r"version = {attr = \.\.\.} is sabotaging setuptools-scm",
+        match=r"pyproject\.toml: at \[tool\.setuptools\.dynamic\]",
     ):
         pyproject_data = read_pyproject(
             _given_definition={