Switch from flake8 to ruff (#217)

MANIFEST.in

@@ -1,7 +1,6 @@
 include *.rst
-include tox.ini
+include pyproject.toml
 include requirements-dev.txt
-include requirements-flake8.txt
 include Makefile
 include LICENSE
 include .readthedocs.yaml

Makefile

@@ -13,8 +13,8 @@ test:  ## Run tests, linting, and static typechecking
 .PHONY: lint
 lint:  ## Lint and black reformat files
 	# NOTE(willkg): Make sure this matches what's in tox.ini.
-	black --target-version=py37 --line-length=88 src setup.py tests docs examples
-	tox -e py37-flake8
+	black src setup.py tests docs examples
+	tox -e py37-lint
 
 .PHONY: clean
 clean:  ## Clean build artifacts

examples/recipes_appconfig.py

@@ -17,11 +17,11 @@
 def parse_loglevel(value):
     try:
         return TEXT_TO_LOGGING_LEVEL[value.upper()]
-    except KeyError:
+    except KeyError as exc:
         raise ValueError(
             f'"{value}" is not a valid logging level. Try CRITICAL, ERROR, '
             "WARNING, INFO, DEBUG"
-        )
+        ) from exc
 
 
 class AppConfig:

pyproject.toml

@@ -0,0 +1,78 @@
+[tool.ruff]
+# Enable pycodestyle (E), pyflakes (F), and bugbear (B) rules
+select = ["E", "F", "B"]
+
+# Ignore line length violations--Black handles those
+line-length = 88
+ignore = ["E501"]
+
+target-version = "py37"
+
+src = ["src"]
+
+[tool.ruff.flake8-quotes]
+docstring-quotes = "double"
+
+
+[tool.black]
+line-length = 88
+target-version = ["py37"]
+
+[tool.mypy]
+python_version = "3.8"
+disallow_untyped_defs = true
+
+[[tool.mypy.overrides]]
+module = "configobj.*"
+ignore_missing_imports = true
+
+[[tool.mypy.overrides]]
+module = "docutils.*"
+ignore_missing_imports = true
+
+
+[tool.pytest.ini_options]
+filterwarnings = [
+    "error",
+    "ignore:::babel[.*]",
+    "ignore:::jinja2[.*]",
+    "ignore:::yaml[.*]",
+    # Sphinx 4.2.0 uses distutils and it's deprecated in 3.10
+    "ignore::DeprecationWarning:sphinx",
+]
+
+
+[tool.tox]
+legacy_tox_ini = """
+[tox]
+envlist = py37,py38,py39,py310,py311,py37-doctest,py37-lint,py38-typecheck
+
+[gh-actions]
+python =
+    3.7: py37
+    3.8: py38
+    3.9: py39
+    3.10: py310
+    3.11: py311
+
+[testenv]
+deps = -rrequirements-dev.txt
+commands = pytest {posargs} tests/
+
+[testenv:py37-doctest]
+deps = -rrequirements-dev.txt
+commands = pytest --doctest-modules src/
+
+[testenv:py37-lint]
+basepython = python3.7
+changedir = {toxinidir}
+commands =
+    black --check src setup.py tests docs examples
+    ruff src setup.py tests docs examples
+
+[testenv:py38-typecheck]
+basepython = python3.8
+changedir = {toxinidir}
+commands =
+    mypy src/everett/
+"""

requirements-dev.txt

@@ -6,6 +6,7 @@ check-manifest==0.49
 cogapp==3.3.0
 mypy==1.1.1
 pytest==7.2.2
+ruff==0.0.262
 tox==4.4.7
 tox-gh-actions==3.1.0
 twine==4.0.2

src/everett/manager.py

@@ -213,18 +213,18 @@ def get_config_for_class(cls: Type) -> Dict[str, Tuple[Option, Type]]:
 
     """
     options = {}
-    for cls in reversed(cls.__mro__):
-        if not hasattr(cls, "Config"):
+    for subcls in reversed(cls.__mro__):
+        if not hasattr(subcls, "Config"):
             continue
 
-        cls_config = cls.Config
-        for attr in cls_config.__dict__.keys():
+        subcls_config = subcls.Config
+        for attr in subcls_config.__dict__.keys():
             if attr.startswith("__"):
                 continue
 
-            val = getattr(cls_config, attr)
+            val = getattr(subcls_config, attr)
             if isinstance(val, Option):
-                options[attr] = (val, cls)
+                options[attr] = (val, subcls)
     return options
 
 
@@ -341,8 +341,10 @@ def parse_class(val: str) -> Any:
     module = importlib.import_module(module_name)
     try:
         return getattr(module, class_name)
-    except AttributeError:
-        raise ValueError(f"{class_name!r} is not a valid member of {qualname(module)}")
+    except AttributeError as exc:
+        raise ValueError(
+            f"{class_name!r} is not a valid member of {qualname(module)}"
+        ) from exc
 
 
 _DATA_SIZE_METRIC_TO_MULTIPLIER = {
@@ -1274,11 +1276,11 @@ def __call__(
         if self.bound_component:
             try:
                 option, cls = self.bound_component_options[key]
-            except KeyError:
+            except KeyError as exc:
                 if raise_error:
                     raise InvalidKeyError(
                         f"{key!r} is not a valid key for this component"
-                    )
+                    ) from exc
                 return None
 
             default = option.default
@@ -1326,7 +1328,7 @@ def __call__(
                         # Re-raise ConfigurationError and friends since that's
                         # what we want to be raising.
                         raise
-                    except Exception:
+                    except Exception as exc:
                         exc_type, exc_value, exc_traceback = sys.exc_info()
                         exc_type_name = exc_type.__name__ if exc_type else "None"
 
@@ -1339,7 +1341,7 @@ def __call__(
                             config_doc=self.doc,
                         )
 
-                        raise InvalidValueError(msg, namespace, key, parser)
+                        raise InvalidValueError(msg, namespace, key, parser) from exc
 
         # Return the default if there is one
         if default is not NO_VALUE:
@@ -1353,7 +1355,7 @@ def __call__(
                 # Re-raise ConfigurationError and friends since that's
                 # what we want to be raising.
                 raise
-            except Exception:
+            except Exception as exc:
                 # FIXME(willkg): This is a programmer error--not a user
                 # configuration error. We might want to denote that better.
                 exc_type, exc_value, exc_traceback = sys.exc_info()
@@ -1368,7 +1370,7 @@ def __call__(
                     config_doc=self.doc,
                 )
 
-                raise InvalidValueError(msg, namespace, key, parser)
+                raise InvalidValueError(msg, namespace, key, parser) from exc
 
         # No value specified and no default, so raise an error to the user
         if raise_error:

src/everett/sphinxext.py

@@ -26,7 +26,7 @@
 from sphinx.addnodes import desc_signature, pending_xref
 from sphinx.directives import ObjectDescription
 from sphinx.domains import Domain, ObjType
-from sphinx.locale import _
+from sphinx.locale import _ as gettext
 from sphinx.roles import XRefRole
 from sphinx.util import ws_re
 from sphinx.util import logging
@@ -165,7 +165,7 @@ def add_target_and_index(
 
             objects[key] = (self.env.docname, targetname)
 
-        indextext = _("%s (component)") % name
+        indextext = gettext("%s (component)") % name
         if self.indexnode is not None:
             self.indexnode["entries"].append(
                 ("single", indextext, targetname, "", None)
@@ -206,7 +206,7 @@ class EverettComponent(ObjectDescription):
         Field(
             "options",
             names=("option",),
-            label=_("Options"),
+            label=gettext("Options"),
             rolename="option",
         )
     ]
@@ -261,7 +261,7 @@ def add_target_and_index(
                 )
             objects[key] = (self.env.docname, targetname)
 
-        indextext = _("%s (component)") % name
+        indextext = gettext("%s (component)") % name
         if self.indexnode is not None:
             self.indexnode["entries"].append(
                 ("single", indextext, targetname, "", None)
@@ -282,8 +282,8 @@ class EverettDomain(Domain):
     label = "Everett"
 
     object_types = {
-        "component": ObjType(_("component"), "component"),
-        "option": ObjType(_("option"), "option"),
+        "component": ObjType(gettext("component"), "component"),
+        "option": ObjType(gettext("option"), "option"),
     }
     directives = {
         "component": EverettComponent,
@@ -474,7 +474,7 @@ def extract_configuration(
         options: List[Dict] = []
 
         # Go through options and figure out relevant information
-        for key, (option, cls) in config.items():
+        for key, (option, _) in config.items():
             if namespace:
                 namespaced_key = namespace + "_" + key
             else:

tests/test_manager.py

@@ -297,8 +297,8 @@ class Namespace:
             pass
 
         obj = Namespace()
-        setattr(obj, "foo", "bar")
-        setattr(obj, "foo_baz", "bar")
+        setattr(obj, "foo", "bar")  # noqa
+        setattr(obj, "foo_baz", "bar")  # noqa
 
         coe = ConfigObjEnv(obj)
         assert coe.get("foo") == "bar"