Fix references to IValidator; add protocol tests

Several remaining cases referred to `IValidator` which is now just
`Validtator`. Fix these.

Add a test which ensures that all valdiators pass
`isinstance(x, Validator)` using the runtime-checkable protocol.

7 files changed, 32 insertions, 10 deletions

diff --git a/README.rst b/README.rst
index fcb11f1..ee5f54b 100644
--- a/README.rst
+++ b/README.rst
@@ -74,7 +74,7 @@ Features
   and
   `Draft 3 <https://python-jsonschema.readthedocs.io/en/latest/validate/#jsonschema.Draft3Validator>`_
 
-* `Lazy validation <https://python-jsonschema.readthedocs.io/en/latest/validate/#jsonschema.IValidator.iter_errors>`_
+* `Lazy validation <https://python-jsonschema.readthedocs.io/en/latest/validate/#jsonschema.Validator.iter_errors>`_
   that can iteratively report *all* validation errors.
 
 * `Programmatic querying <https://python-jsonschema.readthedocs.io/en/latest/errors/>`_
diff --git a/docs/spelling-wordlist.txt b/docs/spelling-wordlist.txt
index 7a6627b..36805a1 100644
--- a/docs/spelling-wordlist.txt
+++ b/docs/spelling-wordlist.txt
@@ -1,5 +1,5 @@
 # this appears to be misinterpreting Napoleon types as prose, sigh...
-IValidator
+Validator
 TypeChecker
 UnknownType
 ValidationError
diff --git a/docs/validate.rst b/docs/validate.rst
index 576b0c5..6be8f9c 100644
--- a/docs/validate.rst
+++ b/docs/validate.rst
@@ -38,7 +38,7 @@ more information see `creating-validators`.
 Type Checking
 -------------
 
-To handle JSON Schema's :validator:`type` property, a `IValidator` uses
+To handle JSON Schema's :validator:`type` property, a `Validator` uses
 an associated `TypeChecker`. The type checker provides an immutable
 mapping between names of types and functions that can test if an instance is
 of that type. The defaults are suitable for most users - each of the
@@ -82,7 +82,7 @@ given how common validating these types are.
 If you *do* want the generality, or just want to add a few specific additional
 types as being acceptable for a validator object, then you should update an
 existing `TypeChecker` or create a new one. You may then create a new
-`IValidator` via `jsonschema.validators.extend`.
+`Validator` via `jsonschema.validators.extend`.
 
 .. code-block:: python
 
@@ -110,7 +110,7 @@ Versioned Validators
 
 `jsonschema` ships with validator classes for various versions of
 the JSON Schema specification. For details on the methods and attributes
-that each validator class provides see the `IValidator` interface,
+that each validator class provides see the `Validator` interface,
 which each included validator class implements.
 
 .. autoclass:: Draft202012Validator
@@ -155,7 +155,7 @@ JSON Schema defines the :validator:`format` property which can be used to check
 if primitive types (``string``\s, ``number``\s, ``boolean``\s) conform to
 well-defined formats. By default, no validation is enforced, but optionally,
 validation can be enabled by hooking in a format-checking object into an
-`IValidator`.
+`Validator`.
 
 .. doctest::
 
diff --git a/jsonschema/__init__.py b/jsonschema/__init__.py
index c7fa76b..cd2102a 100644
--- a/jsonschema/__init__.py
+++ b/jsonschema/__init__.py
@@ -26,6 +26,7 @@ from jsonschema.exceptions import (
     SchemaError,
     ValidationError,
 )
+from jsonschema.protocols import Validator
 from jsonschema.validators import (
     Draft3Validator,
     Draft4Validator,
diff --git a/jsonschema/_types.py b/jsonschema/_types.py
index 6ba2bad..f24e433 100644
--- a/jsonschema/_types.py
+++ b/jsonschema/_types.py
@@ -49,7 +49,7 @@ class TypeChecker(object):
     """
     A ``type`` property checker.
 
-    A `TypeChecker` performs type checking for an `IValidator`. Type
+    A `TypeChecker` performs type checking for a `Validator`. Type
     checks to perform are updated using `TypeChecker.redefine` or
     `TypeChecker.redefine_many` and removed via `TypeChecker.remove`.
     Each of these return a new `TypeChecker` object.
diff --git a/jsonschema/tests/test_validators.py b/jsonschema/tests/test_validators.py
index 429f868..9e52ce9 100644
--- a/jsonschema/tests/test_validators.py
+++ b/jsonschema/tests/test_validators.py
@@ -13,7 +13,13 @@ import warnings
 
 import attr
 
-from jsonschema import FormatChecker, TypeChecker, exceptions, validators
+from jsonschema import (
+    FormatChecker,
+    TypeChecker,
+    exceptions,
+    protocols,
+    validators,
+)
 from jsonschema.tests._helpers import bug
 
 
@@ -2128,6 +2134,21 @@ class TestRefResolver(TestCase):
         self.assertIn("Failed to pop the scope", str(exc.exception))
 
 
+class TestValidatorProtocol(TestCase):
+    def test_each_validator_is_instance_of_protocol(self):
+        schema = {}
+        for validator_cls in [
+            validators.Draft3Validator,
+            validators.Draft4Validator,
+            validators.Draft6Validator,
+            validators.Draft7Validator,
+            validators.Draft201909Validator,
+            validators.Draft202012Validator,
+        ]:
+            validator = validator_cls(schema)
+            assert isinstance(validator, protocols.Validator)
+
+
 def sorted_errors(errors):
     def key(error):
         return (
diff --git a/jsonschema/validators.py b/jsonschema/validators.py
index c229efc..e037c4b 100644
--- a/jsonschema/validators.py
+++ b/jsonschema/validators.py
@@ -917,7 +917,7 @@ def validate(instance, schema, cls=None, *args, **kwargs):
 
     If you know you have a valid schema already, especially if you
     intend to validate multiple instances with the same schema, you
-    likely would prefer using the `IValidator.validate` method directly
+    likely would prefer using the `Validator.validate` method directly
     on a specific validator (e.g. ``Draft7Validator.validate``).
 
 
@@ -931,7 +931,7 @@ def validate(instance, schema, cls=None, *args, **kwargs):
 
             The schema to validate with
 
-        cls (IValidator):
+        cls (Validator):
 
             The class that will be used to validate the instance.