Make use of simplejson optional

simplejson doesnt provide any benefits on Python 3, and
isnt consistent on Python 2 between CPython and PyPy.
Use the standard library json if simplejson is not installed.

Use PyYaml for tests on Python 2 as it puts strings into str
on Python 2 whereas json uses type unicode, causing many test
failures due to u'..' prefix in error messages.

Add PyPy to build and support matrix.

.travis.yml

@@ -6,4 +6,6 @@ python:
     - "3.4"
     - "3.5"
     - "nightly"
+    - "pypy"
+    - "pypy3"
 script: python setup.py test

doc/installation.rst

@@ -6,7 +6,6 @@ Prerequisites
 
 This package has the following prerequisites:
 
-* simplejson 
 * versiontools
 
 To run the test suite you will also need:

json_schema_validator/shortcuts.py

@@ -20,16 +20,22 @@
 One liners that make the code shorter
 """
 
-import simplejson
+try:
+    import simplejson as json
+except ImportError:
+    import json
 
 from json_schema_validator.schema import Schema
 from json_schema_validator.validator import Validator
 
+_default_deserializer = json.loads
 
-def validate(schema_text, data_text):
+
+def validate(schema_text, data_text, deserializer=_default_deserializer):
     """
     Validate specified JSON text (data_text) with specified schema (schema
-    text). Both are converted to JSON objects with :func:`simplesjon.loads`.
+    text). Both are converted to JSON objects with :func:`simplejson.loads`
+    if present or :func:`json.loads`.
 
     :param schema_text:
         Text of the JSON schema to check against
@@ -39,11 +45,16 @@ def validate(schema_text, data_text):
         Text of the JSON object to check
     :type data_text:
         :class:`str`
+    :param deserializer:
+        Function to convert the schema and data to JSON objects
+    :type deserializer:
+        :class:`callable`
     :returns:
         Same as :meth:`json_schema_validator.validator.Validator.validate`
     :raises:
         Whatever may be raised by simplejson (in particular
         :class:`simplejson.decoder.JSONDecoderError`, a subclass of :class:`ValueError`)
+        or json
     :raises:
         Whatever may be raised by
         :meth:`json_schema_validator.validator.Validator.validate`. In particular
@@ -52,6 +63,6 @@ def validate(schema_text, data_text):
 
 
     """
-    schema = Schema(simplejson.loads(schema_text))
-    data = simplejson.loads(data_text)
+    schema = Schema(deserializer(schema_text))
+    data = deserializer(data_text)
     return Validator.validate(schema, data)

json_schema_validator/tests/test_schema.py

@@ -20,18 +20,24 @@
 Unit tests for JSON schema
 """
 
+import json
 import sys
 
-import simplejson
-
 from testscenarios import TestWithScenarios
 from testtools import TestCase
 
 from json_schema_validator.errors import SchemaError
 from json_schema_validator.schema import Schema
 
+PY2 = sys.version_info[0] == 2
 PY35 = sys.version_info[0:2] >= (3, 5)
 
+if PY2:
+    import yaml
+    deserializer = yaml.safe_load
+else:
+    deserializer = json.loads
+
 
 class SchemaTests(TestWithScenarios, TestCase):
 
@@ -775,7 +781,12 @@ class SchemaTests(TestWithScenarios, TestCase):
     ]
 
     def test_schema_attribute(self):
-        schema = Schema(simplejson.loads(self.schema))
+        if deserializer != json.loads:
+            # Always check the serialised JSON using the native JSON loader
+            # so that any error messages are consistent and appropriate.
+            json.loads(self.schema)
+
+        schema = Schema(deserializer(self.schema))
         if hasattr(self, 'expected'):
             for attr, expected_value in self.expected.items():
                 self.assertEqual(

json_schema_validator/tests/test_validator.py

@@ -20,6 +20,8 @@
 Unit tests for JSON schema
 """
 
+import functools
+import json
 import sys
 
 from testscenarios import TestWithScenarios
@@ -30,6 +32,16 @@
 from json_schema_validator.validator import Validator
 
 PY2 = sys.version_info[0] == 2
+if PY2:
+    import yaml
+
+    def deserializer(json_string):
+        # Always check the serialised JSON using the native JSON loader
+        # so that any error messages are consistent and appropriate.
+        json.loads(json_string)
+        return yaml.safe_load(json_string)
+
+    validate = functools.partial(validate, deserializer=deserializer)
 
 
 class ValidatorFailureTests(TestWithScenarios, TestCase):
@@ -111,7 +123,6 @@ class ValidatorFailureTests(TestWithScenarios, TestCase):
             'schema': '{"type": "boolean"}',
             'data': '""',
             'raises': ValidationError(
-                ('u' if PY2 else '') +
                 "'' does not match type 'boolean'",
                 "Object has incorrect type (expected boolean)"),
             'object_expr': 'object',
@@ -175,7 +186,6 @@ class ValidatorFailureTests(TestWithScenarios, TestCase):
             'schema': '{"type": "null"}',
             'data': '""',
             'raises': ValidationError(
-                ('u' if PY2 else '') +
                 "'' does not match type 'null'",
                 "Object has incorrect type (expected null)"),
             'object_expr': 'object',

setup.py

@@ -19,8 +19,17 @@
 # You should have received a copy of the GNU Lesser General Public License
 # along with json-schema-validator.  If not, see <http://www.gnu.org/licenses/>.
 
+import sys
+
 from setuptools import setup, find_packages
 
+test_dependencies = [
+    'testscenarios >= 0.1',
+    'testtools >= 0.9.2'
+]
+
+if sys.version_info[0] == 2:
+    test_dependencies.append('PyYaml')
 
 setup(
     name='json-schema-validator',
@@ -40,12 +49,10 @@
         "Programming Language :: Python :: 2.6",
         "Programming Language :: Python :: 2.7",
         "Programming Language :: Python :: 3",
+        "Programming Language :: Python :: Implementation :: CPython",
+        "Programming Language :: Python :: Implementation :: PyPy",
     ],
-    install_requires=[
-        'simplejson >= 2.0.9'],
     setup_requires=[
         'versiontools >= 1.3.1'],
-    tests_require=[
-        'testscenarios >= 0.1',
-        'testtools >= 0.9.2'],
+    tests_require=test_dependencies,
     zip_safe=True)

tox.ini

@@ -7,7 +7,7 @@ commands=
     sphinx-build -b doctest doc html
     sphinx-build doc html
 deps= 
-    simplejson
+    PyYAML
     sphinx
     testscenarios
     testtools