flake8 -> ruff, a mostly painless affair.

jsonschema/__init__.py

@@ -1,5 +1,5 @@
 """
-An implementation of JSON Schema for Python
+An implementation of JSON Schema for Python.
 
 The main functionality is provided by the validator classes for each of the
 supported JSON Schema versions.
@@ -98,3 +98,19 @@ def __getattr__(name):
         return ValidatorForFormat.FORMAT_CHECKER
 
     raise AttributeError(f"module {__name__} has no attribute {name}")
+
+
+__all__ = [
+    "Draft201909Validator",
+    "Draft202012Validator",
+    "Draft3Validator",
+    "Draft4Validator",
+    "Draft6Validator",
+    "Draft7Validator",
+    "FormatChecker",
+    "SchemaError",
+    "TypeChecker",
+    "ValidationError",
+    "Validator",
+    "validate",
+]

jsonschema/__main__.py

@@ -1,3 +1,6 @@
+"""
+The jsonschema CLI is now deprecated in favor of check-jsonschema.
+"""
 from jsonschema.cli import main
 
 main()

jsonschema/_format.py

@@ -51,9 +51,9 @@ def __init__(self, formats: typing.Iterable[str] | None = None):
         self.checkers = {k: self.checkers[k] for k in formats}
 
     def __repr__(self):
-        return "<FormatChecker checkers={}>".format(sorted(self.checkers))
+        return f"<FormatChecker checkers={sorted(self.checkers)}>"
 
-    def checks(
+    def checks(  # noqa: D417,D214,D405 (charliermarsh/ruff#3547)
         self, format: str, raises: _RaisesType = (),
     ) -> typing.Callable[[_F], _F]:
         """
@@ -73,7 +73,7 @@ def checks(
                 The exception object will be accessible as the
                 `jsonschema.exceptions.ValidationError.cause` attribute of the
                 resulting validation error.
-        """
+        """  # noqa: D417,D214,D405 (charliermarsh/ruff#3547)
 
         def _checks(func: _F) -> _F:
             self.checkers[format] = (func, raises)
@@ -126,7 +126,6 @@ def check(self, instance: object, format: str) -> None:
 
                 if the instance does not conform to ``format``
         """
-
         if format not in self.checkers:
             return
 
@@ -157,7 +156,6 @@ def conforms(self, instance: object, format: str) -> bool:
 
             bool: whether it conformed
         """
-
         try:
             self.check(instance, format)
         except FormatError:

jsonschema/_legacy_validators.py

@@ -222,7 +222,7 @@ def recursiveRef(validator, recursiveRef, instance, schema):
 
 def find_evaluated_item_indexes_by_schema(validator, instance, schema):
     """
-    Get all indexes of items that get evaluated under the current schema
+    Get all indexes of items that get evaluated under the current schema.
 
     Covers all keywords related to unevaluatedItems: items, prefixItems, if,
     then, else, contains, unevaluatedItems, allOf, oneOf, anyOf

jsonschema/_types.py

@@ -14,8 +14,8 @@
 # the concrete type of a type checker mapping
 # this "do nothing" wrapper presents the correct information to mypy
 def _typed_map_converter(
-    init_val: Mapping[str, Callable[["TypeChecker", Any], bool]],
-) -> HashTrieMap[str, Callable[["TypeChecker", Any], bool]]:
+    init_val: Mapping[str, Callable[[TypeChecker, Any], bool]],
+) -> HashTrieMap[str, Callable[[TypeChecker, Any], bool]]:
     return HashTrieMap.convert(init_val)
 
 
@@ -79,7 +79,7 @@ class TypeChecker:
     """
 
     _type_checkers: HashTrieMap[
-        str, Callable[["TypeChecker", Any], bool],
+        str, Callable[[TypeChecker, Any], bool],
     ] = attr.ib(
         default=HashTrieMap(),
         converter=_typed_map_converter,
@@ -116,7 +116,7 @@ def is_type(self, instance, type: str) -> bool:
 
         return fn(self, instance)
 
-    def redefine(self, type: str, fn) -> "TypeChecker":
+    def redefine(self, type: str, fn) -> TypeChecker:
         """
         Produce a new checker with the given type redefined.
 
@@ -135,7 +135,7 @@ def redefine(self, type: str, fn) -> "TypeChecker":
         """
         return self.redefine_many({type: fn})
 
-    def redefine_many(self, definitions=()) -> "TypeChecker":
+    def redefine_many(self, definitions=()) -> TypeChecker:
         """
         Produce a new checker with the given types redefined.
 
@@ -148,7 +148,7 @@ def redefine_many(self, definitions=()) -> "TypeChecker":
         type_checkers = self._type_checkers.update(definitions)
         return attr.evolve(self, type_checkers=type_checkers)
 
-    def remove(self, *types) -> "TypeChecker":
+    def remove(self, *types) -> TypeChecker:
         """
         Produce a new checker with the given types forgotten.
 
@@ -164,7 +164,6 @@ def remove(self, *types) -> "TypeChecker":
 
                 if any given type is unknown to this object
         """
-
         type_checkers = self._type_checkers
         for each in types:
             try:

jsonschema/exceptions.py

@@ -51,7 +51,7 @@ def __init__(
         parent=None,
         type_checker=_unset,
     ):
-        super(_Error, self).__init__(
+        super().__init__(
             message,
             validator,
             path,
@@ -252,7 +252,7 @@ class FormatError(Exception):
     """
 
     def __init__(self, message, cause=None):
-        super(FormatError, self).__init__(message, cause)
+        super().__init__(message, cause)
         self.message = message
         self.cause = self.__cause__ = cause
 
@@ -283,7 +283,6 @@ def __contains__(self, index):
         """
         Check whether ``instance[index]`` has any errors.
         """
-
         return index in self._contents
 
     def __getitem__(self, index):
@@ -295,7 +294,6 @@ def __getitem__(self, index):
         by ``instance.__getitem__`` will be propagated (usually this is
         some subclass of `LookupError`.
         """
-
         if self._instance is not _unset and index not in self:
             self._instance[index]
         return self._contents[index]
@@ -310,7 +308,6 @@ def __iter__(self):
         """
         Iterate (non-recursively) over the indices in the instance with errors.
         """
-
         return iter(self._contents)
 
     def __len__(self):
@@ -329,7 +326,6 @@ def total_errors(self):
         """
         The total number of errors in the entire tree, including children.
         """
-
         child_errors = sum(len(tree) for _, tree in self._contents.items())
         return len(self.errors) + child_errors
 

jsonschema/protocols.py

@@ -206,7 +206,7 @@ def validate(self, instance: Any) -> None:
         ValidationError: [2, 3, 4] is too long
         """
 
-    def evolve(self, **kwargs) -> "Validator":
+    def evolve(self, **kwargs) -> Validator:
         """
         Create a new validator like this one, but with given changes.
 

jsonschema/tests/test_jsonschema_test_suite.py

@@ -39,7 +39,7 @@ def missing_format(test):  # pragma: no cover
         ):
             return
 
-        return "Format checker {0!r} not found.".format(schema["format"])
+        return f"Format checker {schema['format']!r} not found."
     return missing_format
 
 

jsonschema/tests/test_validators.py

@@ -1522,7 +1522,7 @@ def test_schema_with_invalid_regex_with_disabled_format_validation(self):
         )
 
 
-class ValidatorTestMixin(MetaSchemaTestsMixin, object):
+class ValidatorTestMixin(MetaSchemaTestsMixin):
     def test_it_implements_the_validator_protocol(self):
         self.assertIsInstance(self.Validator({}), protocols.Validator)
 
@@ -1632,7 +1632,7 @@ def check(value):
             elif value == "bad":
                 raise bad
             else:  # pragma: no cover
-                self.fail("What is {}? [Baby Don't Hurt Me]".format(value))
+                self.fail(f"What is {value}? [Baby Don't Hurt Me]")
 
         validator = self.Validator(
             {"format": "foo"}, format_checker=checker,
@@ -2201,7 +2201,7 @@ def test_it_retrieves_local_refs_via_urlopen(self):
             self.addCleanup(os.remove, tempf.name)
             json.dump({"foo": "bar"}, tempf)
 
-        ref = "file://{}#foo".format(pathname2url(tempf.name))
+        ref = f"file://{pathname2url(tempf.name)}#foo"
         with self.resolver.resolving(ref) as resolved:
             self.assertEqual(resolved, "bar")
 

jsonschema/validators.py

@@ -518,7 +518,6 @@ def extend(
         likely be made before modifying it, in order to not affect the
         old validator.
     """
-
     all_validators = dict(validator.VALIDATORS)
     all_validators.update(validators)
 
@@ -892,7 +891,7 @@ def __init__(
         self._remote_cache = remote_cache
 
     @classmethod
-    def from_schema(
+    def from_schema(  # noqa: D417
         cls,
         schema,
         id_of=referencing.jsonschema.DRAFT202012.id_of,
@@ -912,7 +911,6 @@ def from_schema(
 
             `_RefResolver`
         """
-
         return cls(base_uri=id_of(schema) or "", referrer=schema, *args, **kwargs)  # noqa: B026, E501
 
     def push_scope(self, scope):
@@ -992,7 +990,6 @@ def resolving(self, ref):
 
                 The reference to resolve
         """
-
         url, resolved = self.resolve(ref)
         self.push_scope(url)
         try:
@@ -1003,7 +1000,7 @@ def resolving(self, ref):
     def _find_in_referrer(self, key):
         return self._get_subschemas_cache()[key]
 
-    @lru_cache()  # noqa: B019
+    @lru_cache  # noqa: B019
     def _get_subschemas_cache(self):
         cache = {key: [] for key in _SUBSCHEMAS_KEYWORDS}
         for keyword, subschema in _search_schema(
@@ -1012,7 +1009,7 @@ def _get_subschemas_cache(self):
             cache[keyword].append(subschema)
         return cache
 
-    @lru_cache()  # noqa: B019
+    @lru_cache  # noqa: B019
     def _find_in_subschemas(self, url):
         subschemas = self._get_subschemas_cache()["$id"]
         if not subschemas:
@@ -1073,7 +1070,6 @@ def resolve_fragment(self, document, fragment):
 
                 a URI fragment to resolve within it
         """
-
         fragment = fragment.lstrip("/")
 
         if not fragment:
@@ -1196,7 +1192,7 @@ def _search_schema(schema, matcher):
         values.extendleft(value.values())
 
 
-def validate(instance, schema, cls=None, *args, **kwargs):
+def validate(instance, schema, cls=None, *args, **kwargs):  # noqa: D417
     """
     Validate an instance under the given schema.
 
@@ -1323,7 +1319,6 @@ class is returned:
         recommended.
 
     """
-
     DefaultValidator = _LATEST_VERSION if default is _UNSET else default
 
     if schema is True or schema is False or "$schema" not in schema:

pyproject.toml

@@ -111,15 +111,46 @@ multi_line_output = 3
 ignore_missing_imports = true
 show_error_codes = true
 
-[tool.pydocstyle]
-match = "(?!(test_|_|compat|cli)).*\\.py"  # see PyCQA/pydocstyle#323
-add-select = [
-  "D410", # Trailing whitespace plz
-]
-add-ignore = [
-  "D107",  # Hah, no
-  "D200",  # 1-line docstrings don't need to be on one line
-  "D202",  # One line is fine.
-  "D412",  # Trailing whitespace plz
-  "D413",  # No trailing whitespace plz
+[tool.ruff]
+line-length = 79
+target-version = "py38"
+select = ["B", "D", "D204", "E", "F", "Q", "UP", "W"]
+ignore = [
+  # It's totally OK to call functions for default arguments.
+  "B008",
+  # raise SomeException(...) is fine.
+  "B904",
+  # It's fine to not have docstrings for magic methods.
+  "D105",
+  # __init__ especially doesn't need a docstring
+  "D107",
+  # This rule makes diffs uglier when expanding docstrings (and it's uglier)
+  "D200",
+  # No blank lines before docstrings.
+  "D203",
+  # Start docstrings on the second line.
+  "D212",
+  # This rule misses sassy docstrings ending with ! or ?.
+  "D400",
+  # Section headers should end with a colon not a newline
+  "D406",
+  # Underlines aren't needed
+  "D407",
+  # Plz spaces after section headers
+  "D412",
 ]
+extend-exclude = ["json"]
+
+[tool.ruff.flake8-quotes]
+docstring-quotes = "double"
+
+[tool.ruff.per-file-ignores]
+"docs/*" = ["D"]
+"jsonschema/cli.py" = ["D", "UP"]
+"jsonschema/_utils.py" = ["D"]
+"jsonschema/benchmarks/*" = ["D"]
+"jsonschema/tests/*" = ["D"]
+
+[tool.ruff.pyupgrade]
+# We support 3.8 + 3.9
+keep-runtime-typing = true

tox.ini

@@ -76,15 +76,8 @@ deps = detect-secrets
 commands = {envbindir}/detect-secrets scan {toxinidir}
 
 [testenv:style]
-deps =
-    flake8
-    flake8-broken-line
-    flake8-bugbear
-    flake8-commas
-    flake8-quotes
-    flake8-tidy-imports
-commands =
-    {envpython} -m flake8 {posargs} {toxinidir}/jsonschema {toxinidir}/docs
+deps = ruff
+commands = {envpython} -m ruff check {toxinidir}
 
 [testenv:typing]
 skip_install = true