Add a linter to ensure single quotes aren't added.

8 files changed, 61 insertions, 60 deletions

diff --git a/jsonschema/_utils.py b/jsonschema/_utils.py
index 9b02513..9142cc5 100644
--- a/jsonschema/_utils.py
+++ b/jsonschema/_utils.py
@@ -64,7 +64,7 @@ def load_vocabulary(name):
     """
     vocabulary = []
     base_path = os.path.dirname(sys.modules["jsonschema"].__file__)
-    pathlist = Path(os.path.join(base_path, 'schemas', name)).glob('*.json')
+    pathlist = Path(os.path.join(base_path, "schemas", name)).glob("*.json")
     for path in pathlist:
         with open(path) as data:
             vocabulary.append(json.load(data))
diff --git a/jsonschema/_validators.py b/jsonschema/_validators.py
index 75857f1..39680cf 100644
--- a/jsonschema/_validators.py
+++ b/jsonschema/_validators.py
@@ -73,15 +73,15 @@ def items(validator, items, instance, schema):
     if not validator.is_type(instance, "array"):
         return
 
-    if validator.is_type(items, "boolean") and 'prefixItems' in schema:
+    if validator.is_type(items, "boolean") and "prefixItems" in schema:
         if not items:
-            if len(instance) > len(schema['prefixItems']):
+            if len(instance) > len(schema["prefixItems"]):
                 yield ValidationError(
                     "%r has more items than defined in prefixItems" % instance,
                 )
     else:
-        non_prefixed_items = instance[len(schema['prefixItems']):] \
-            if 'prefixItems' in schema else instance
+        non_prefixed_items = instance[len(schema["prefixItems"]):] \
+            if "prefixItems" in schema else instance
 
         for index, item in enumerate(non_prefixed_items):
             for error in validator.descend(item, items, path=index):
@@ -119,11 +119,11 @@ def contains(validator, contains, instance, schema):
 
     min_contains = max_contains = None
 
-    if 'minContains' in schema:
-        min_contains = schema['minContains']
+    if "minContains" in schema:
+        min_contains = schema["minContains"]
 
-    if 'maxContains' in schema:
-        max_contains = schema['maxContains']
+    if "maxContains" in schema:
+        max_contains = schema["maxContains"]
 
     # minContains set to 0 will ignore contains
     if min_contains == 0:
diff --git a/jsonschema/exceptions.py b/jsonschema/exceptions.py
index 9cfbb7f..e8da352 100644
--- a/jsonschema/exceptions.py
+++ b/jsonschema/exceptions.py
@@ -112,12 +112,12 @@ class _Error(Exception):
 
     @property
     def json_path(self):
-        path = '$'
+        path = "$"
         for elem in self.absolute_path:
             if isinstance(elem, int):
-                path += '[' + str(elem) + ']'
+                path += "[" + str(elem) + "]"
             else:
-                path += '.' + elem
+                path += "." + elem
         return path
 
     def _set(self, **kwargs):
diff --git a/jsonschema/tests/test_cli.py b/jsonschema/tests/test_cli.py
index fa29b48..ce2d298 100644
--- a/jsonschema/tests/test_cli.py
+++ b/jsonschema/tests/test_cli.py
@@ -699,7 +699,7 @@ class TestCLI(TestCase):
         schema = f'{{"$ref": "{ref_path.name}#definitions/num"}}'
 
         self.assertOutputs(
-            files=dict(some_schema=schema, some_instance='1'),
+            files=dict(some_schema=schema, some_instance="1"),
             argv=[
                 "-i", "some_instance",
                 "--base-uri", ref_path.parent.as_uri() + "/",
diff --git a/jsonschema/tests/test_validators.py b/jsonschema/tests/test_validators.py
index 820952d..68bc5de 100644
--- a/jsonschema/tests/test_validators.py
+++ b/jsonschema/tests/test_validators.py
@@ -446,7 +446,7 @@ class TestValidationErrorDetails(TestCase):
         self.assertEqual(e.path, deque([]))
         self.assertEqual(e.relative_path, deque([]))
         self.assertEqual(e.absolute_path, deque([]))
-        self.assertEqual(e.json_path, '$')
+        self.assertEqual(e.json_path, "$")
 
         self.assertEqual(e.schema_path, deque(["anyOf"]))
         self.assertEqual(e.relative_schema_path, deque(["anyOf"]))
@@ -465,7 +465,7 @@ class TestValidationErrorDetails(TestCase):
         self.assertEqual(e1.path, deque([]))
         self.assertEqual(e1.absolute_path, deque([]))
         self.assertEqual(e1.relative_path, deque([]))
-        self.assertEqual(e1.json_path, '$')
+        self.assertEqual(e1.json_path, "$")
 
         self.assertEqual(e1.schema_path, deque([0, "minimum"]))
         self.assertEqual(e1.relative_schema_path, deque([0, "minimum"]))
@@ -484,7 +484,7 @@ class TestValidationErrorDetails(TestCase):
         self.assertEqual(e2.path, deque([]))
         self.assertEqual(e2.relative_path, deque([]))
         self.assertEqual(e2.absolute_path, deque([]))
-        self.assertEqual(e2.json_path, '$')
+        self.assertEqual(e2.json_path, "$")
 
         self.assertEqual(e2.schema_path, deque([1, "type"]))
         self.assertEqual(e2.relative_schema_path, deque([1, "type"]))
@@ -518,7 +518,7 @@ class TestValidationErrorDetails(TestCase):
         self.assertEqual(e.path, deque([]))
         self.assertEqual(e.relative_path, deque([]))
         self.assertEqual(e.absolute_path, deque([]))
-        self.assertEqual(e.json_path, '$')
+        self.assertEqual(e.json_path, "$")
 
         self.assertEqual(e.schema_path, deque(["type"]))
         self.assertEqual(e.relative_schema_path, deque(["type"]))
@@ -537,7 +537,7 @@ class TestValidationErrorDetails(TestCase):
         self.assertEqual(e1.path, deque([]))
         self.assertEqual(e1.relative_path, deque([]))
         self.assertEqual(e1.absolute_path, deque([]))
-        self.assertEqual(e1.json_path, '$')
+        self.assertEqual(e1.json_path, "$")
 
         self.assertEqual(e1.schema_path, deque([0, "type"]))
         self.assertEqual(e1.relative_schema_path, deque([0, "type"]))
@@ -554,7 +554,7 @@ class TestValidationErrorDetails(TestCase):
         self.assertEqual(e2.path, deque(["foo"]))
         self.assertEqual(e2.relative_path, deque(["foo"]))
         self.assertEqual(e2.absolute_path, deque(["foo"]))
-        self.assertEqual(e2.json_path, '$.foo')
+        self.assertEqual(e2.json_path, "$.foo")
 
         self.assertEqual(
             e2.schema_path, deque([1, "properties", "foo", "enum"]),
@@ -598,10 +598,10 @@ class TestValidationErrorDetails(TestCase):
         self.assertEqual(e3.absolute_path, deque(["baz"]))
         self.assertEqual(e4.absolute_path, deque(["foo"]))
 
-        self.assertEqual(e1.json_path, '$.bar')
-        self.assertEqual(e2.json_path, '$.baz')
-        self.assertEqual(e3.json_path, '$.baz')
-        self.assertEqual(e4.json_path, '$.foo')
+        self.assertEqual(e1.json_path, "$.bar")
+        self.assertEqual(e2.json_path, "$.baz")
+        self.assertEqual(e3.json_path, "$.baz")
+        self.assertEqual(e4.json_path, "$.foo")
 
         self.assertEqual(e1.validator, "minItems")
         self.assertEqual(e2.validator, "enum")
@@ -638,12 +638,12 @@ class TestValidationErrorDetails(TestCase):
         self.assertEqual(e5.path, deque([1, "bar", "baz"]))
         self.assertEqual(e6.path, deque([1, "foo"]))
 
-        self.assertEqual(e1.json_path, '$')
-        self.assertEqual(e2.json_path, '$[0]')
-        self.assertEqual(e3.json_path, '$[1].bar')
-        self.assertEqual(e4.json_path, '$[1].bar.bar')
-        self.assertEqual(e5.json_path, '$[1].bar.baz')
-        self.assertEqual(e6.json_path, '$[1].foo')
+        self.assertEqual(e1.json_path, "$")
+        self.assertEqual(e2.json_path, "$[0]")
+        self.assertEqual(e3.json_path, "$[1].bar")
+        self.assertEqual(e4.json_path, "$[1].bar.bar")
+        self.assertEqual(e5.json_path, "$[1].bar.baz")
+        self.assertEqual(e6.json_path, "$[1].foo")
 
         self.assertEqual(e1.schema_path, deque(["type"]))
         self.assertEqual(e2.schema_path, deque(["items", "type"]))
@@ -720,7 +720,7 @@ class TestValidationErrorDetails(TestCase):
         self.assertEqual(
             e.absolute_schema_path, deque(["properties", "root", "anyOf"]),
         )
-        self.assertEqual(e.json_path, '$.root')
+        self.assertEqual(e.json_path, "$.root")
 
         e1, = e.context
         self.assertEqual(e1.absolute_path, deque(["root", "children", "a"]))
@@ -739,7 +739,7 @@ class TestValidationErrorDetails(TestCase):
                 ],
             ),
         )
-        self.assertEqual(e1.json_path, '$.root.children.a')
+        self.assertEqual(e1.json_path, "$.root.children.a")
 
         e2, = e1.context
         self.assertEqual(
@@ -768,7 +768,7 @@ class TestValidationErrorDetails(TestCase):
                 ],
             ),
         )
-        self.assertEqual(e2.json_path, '$.root.children.a.children.ab')
+        self.assertEqual(e2.json_path, "$.root.children.a.children.ab")
 
     def test_additionalProperties(self):
         instance = {"bar": "bar", "foo": 2}
@@ -781,8 +781,8 @@ class TestValidationErrorDetails(TestCase):
         self.assertEqual(e1.path, deque(["bar"]))
         self.assertEqual(e2.path, deque(["foo"]))
 
-        self.assertEqual(e1.json_path, '$.bar')
-        self.assertEqual(e2.json_path, '$.foo')
+        self.assertEqual(e1.json_path, "$.bar")
+        self.assertEqual(e2.json_path, "$.foo")
 
         self.assertEqual(e1.validator, "type")
         self.assertEqual(e2.validator, "minimum")
@@ -803,8 +803,8 @@ class TestValidationErrorDetails(TestCase):
         self.assertEqual(e1.path, deque(["bar"]))
         self.assertEqual(e2.path, deque(["foo"]))
 
-        self.assertEqual(e1.json_path, '$.bar')
-        self.assertEqual(e2.json_path, '$.foo')
+        self.assertEqual(e1.json_path, "$.bar")
+        self.assertEqual(e2.json_path, "$.foo")
 
         self.assertEqual(e1.validator, "type")
         self.assertEqual(e2.validator, "minimum")
@@ -823,8 +823,8 @@ class TestValidationErrorDetails(TestCase):
         self.assertEqual(e1.path, deque([0]))
         self.assertEqual(e2.path, deque([1]))
 
-        self.assertEqual(e1.json_path, '$[0]')
-        self.assertEqual(e2.json_path, '$[1]')
+        self.assertEqual(e1.json_path, "$[0]")
+        self.assertEqual(e2.json_path, "$[1]")
 
         self.assertEqual(e1.validator, "type")
         self.assertEqual(e2.validator, "minimum")
@@ -843,8 +843,8 @@ class TestValidationErrorDetails(TestCase):
         self.assertEqual(e1.path, deque([1]))
         self.assertEqual(e2.path, deque([2]))
 
-        self.assertEqual(e1.json_path, '$[1]')
-        self.assertEqual(e2.json_path, '$[2]')
+        self.assertEqual(e1.json_path, "$[1]")
+        self.assertEqual(e2.json_path, "$[2]")
 
         self.assertEqual(e1.validator, "type")
         self.assertEqual(e2.validator, "minimum")
@@ -862,7 +862,7 @@ class TestValidationErrorDetails(TestCase):
             "%r is not allowed for %r" % ({"const": "foo"}, "foo"),
         )
         self.assertEqual(error.path, deque([]))
-        self.assertEqual(error.json_path, '$')
+        self.assertEqual(error.json_path, "$")
         self.assertEqual(error.schema_path, deque(["propertyNames", "not"]))
 
     def test_if_then(self):
@@ -877,7 +877,7 @@ class TestValidationErrorDetails(TestCase):
         self.assertEqual(error.validator, "const")
         self.assertEqual(error.message, "13 was expected")
         self.assertEqual(error.path, deque([]))
-        self.assertEqual(error.json_path, '$')
+        self.assertEqual(error.json_path, "$")
         self.assertEqual(error.schema_path, deque(["then", "const"]))
 
     def test_if_else(self):
@@ -892,7 +892,7 @@ class TestValidationErrorDetails(TestCase):
         self.assertEqual(error.validator, "const")
         self.assertEqual(error.message, "13 was expected")
         self.assertEqual(error.path, deque([]))
-        self.assertEqual(error.json_path, '$')
+        self.assertEqual(error.json_path, "$")
         self.assertEqual(error.schema_path, deque(["else", "const"]))
 
     def test_boolean_schema_False(self):
@@ -916,7 +916,7 @@ class TestValidationErrorDetails(TestCase):
                 12,
                 False,
                 deque([]),
-                '$',
+                "$",
             ),
         )
 
@@ -947,7 +947,7 @@ class TestValidationErrorDetails(TestCase):
                 deque(["foo"]),
                 {"type": "integer"},
                 deque(["additionalProperties", "type"]),
-                '$.foo',
+                "$.foo",
             ),
         )
 
@@ -1129,7 +1129,7 @@ class ValidatorTestMixin(MetaSchemaTestsMixin, object):
         Allow array to validate against another defined sequence type
         """
         schema = {"type": "array", "uniqueItems": True}
-        MyMapping = namedtuple('MyMapping', 'a, b')
+        MyMapping = namedtuple("MyMapping", "a, b")
         Validator = validators.extend(
             self.Validator,
             type_checker=self.Validator.TYPE_CHECKER.redefine_many(
@@ -1146,20 +1146,20 @@ class ValidatorTestMixin(MetaSchemaTestsMixin, object):
         validator = Validator(schema)
 
         valid_instances = [
-            deque(['a', None, '1', '', True]),
+            deque(["a", None, "1", "", True]),
             deque([[False], [0]]),
             [deque([False]), deque([0])],
             [[deque([False])], [deque([0])]],
             [[[[[deque([False])]]]], [[[[deque([0])]]]]],
             [deque([deque([False])]), deque([deque([0])])],
-            [MyMapping('a', 0), MyMapping('a', False)],
+            [MyMapping("a", 0), MyMapping("a", False)],
             [
-                MyMapping('a', [deque([0])]),
-                MyMapping('a', [deque([False])]),
+                MyMapping("a", [deque([0])]),
+                MyMapping("a", [deque([False])]),
             ],
             [
-                MyMapping('a', [MyMapping('a', deque([0]))]),
-                MyMapping('a', [MyMapping('a', deque([False]))]),
+                MyMapping("a", [MyMapping("a", deque([0]))]),
+                MyMapping("a", [MyMapping("a", deque([False]))]),
             ],
             [deque(deque(deque([False]))), deque(deque(deque([0])))],
         ]
@@ -1168,20 +1168,20 @@ class ValidatorTestMixin(MetaSchemaTestsMixin, object):
             validator.validate(instance)
 
         invalid_instances = [
-            deque(['a', 'b', 'a']),
+            deque(["a", "b", "a"]),
             deque([[False], [False]]),
             [deque([False]), deque([False])],
             [[deque([False])], [deque([False])]],
             [[[[[deque([False])]]]], [[[[deque([False])]]]]],
             [deque([deque([False])]), deque([deque([False])])],
-            [MyMapping('a', False), MyMapping('a', False)],
+            [MyMapping("a", False), MyMapping("a", False)],
             [
-                MyMapping('a', [deque([False])]),
-                MyMapping('a', [deque([False])]),
+                MyMapping("a", [deque([False])]),
+                MyMapping("a", [deque([False])]),
             ],
             [
-                MyMapping('a', [MyMapping('a', deque([False]))]),
-                MyMapping('a', [MyMapping('a', deque([False]))]),
+                MyMapping("a", [MyMapping("a", deque([False]))]),
+                MyMapping("a", [MyMapping("a", deque([False]))]),
             ],
             [deque(deque(deque([False]))), deque(deque(deque([False])))],
         ]
diff --git a/jsonschema/validators.py b/jsonschema/validators.py
index 295cf6f..c3f7ff9 100644
--- a/jsonschema/validators.py
+++ b/jsonschema/validators.py
@@ -733,7 +733,7 @@ class RefResolver(object):
 
         for subschema in self._finditem(schema, "$id"):
             target_uri = self._urljoin_cache(
-                self.resolution_scope, subschema['$id'],
+                self.resolution_scope, subschema["$id"],
             )
             if target_uri.rstrip("/") == uri.rstrip("/"):
                 if fragment:
diff --git a/setup.cfg b/setup.cfg
index 4c45668..1d002e3 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -61,7 +61,7 @@ jsonschema = schemas/*.json, schemas/*/*.json
 universal = 1
 
 [flake8]
-builtins = unicode
+inline-quotes = "
 exclude =
     jsonschema/__init__.py
     jsonschema/_reflect.py
diff --git a/tox.ini b/tox.ini
index 33de1aa..3098b5f 100644
--- a/tox.ini
+++ b/tox.ini
@@ -84,6 +84,7 @@ commands = {envbindir}/detect-secrets scan {toxinidir}
 deps =
     flake8
     flake8-commas
+    flake8-quotes
 commands =
     {envpython} -m flake8 {posargs} {toxinidir}/jsonschema {toxinidir}/docs