Only allow asserts in tests

docs/source/conf.py

@@ -48,7 +48,11 @@
 requires_python = project_metadata["Requires-Python"]
 specifiers = SpecifierSet(specifiers=requires_python)
 (specifier,) = specifiers
-assert specifier.operator == ">="
+if specifier.operator != ">=":
+    msg = (
+        f"We only support '>=' for Requires-Python, got {specifier.operator}."
+    )
+    raise ValueError(msg)
 minimum_python_version = specifier.version
 
 language = "en"

pyproject.toml

@@ -118,6 +118,9 @@ lint.ignore = [
     "D415",
     # Ruff warns that this conflicts with the formatter.
     "ISC001",
+]
+
+lint.per-file-ignores."tests/*.py" = [
     # Allow 'assert' as we use it for tests.
     "S101",
 ]
@@ -301,6 +304,7 @@ exclude_also = [
 strict = true
 files = [ "." ]
 exclude = [ "build" ]
+follow_untyped_imports = true
 
 [tool.pyright]
 enableTypeIgnoreComments = false