python-jsonschema#708 - limit JSON formatting

Only use JSON formatting for exception messages when explicitly requested.

Author: sloanlance

jsonschema/cli.py

@@ -3,14 +3,14 @@
 """
 
 from __future__ import absolute_import
-from textwrap import dedent
+
 import argparse
-import errno
 import json
-import sys
 import traceback
 
 import attr
+import errno
+import sys
 
 from jsonschema import __version__
 from jsonschema._reflect import namedAny
@@ -105,7 +105,7 @@ def validation_error(self, instance_path, error):
         return self._error_msg(
             path=instance_path,
             type=error.__class__.__name__,
-            body=error,
+            body=error.formatted_message(pretty=True),
         )
 
     def validation_success(self, instance_path):

jsonschema/exceptions.py

@@ -62,14 +62,18 @@ def __init__(
     def __repr__(self):
         return "<%s: %r>" % (self.__class__.__name__, self.message)
 
-    def __unicode__(self):
+    def formatted_message(self, pretty=False):
         essential_for_verbose = (
             self.validator, self.validator_value, self.instance, self.schema,
         )
         if any(m is _unset for m in essential_for_verbose):
             return self.message
 
-        pschema = json.dumps(self.schema, separators=(',\n', ': '), sort_keys=True)
+        if (pretty is True):
+            pschema = json.dumps(self.schema, separators=(',\n', ': '), sort_keys=True)
+        else:
+            pschema = pprint.pformat(self.schema, width=72)
+
         pinstance = pprint.pformat(self.instance, width=72)
         return self.message + textwrap.dedent("""
 
@@ -89,6 +93,9 @@ def __unicode__(self):
             _utils.indent(pinstance),
         )
 
+    def __unicode__(self):
+        return self.formatted_message(pretty=False)
+
     if PY3:
         __str__ = __unicode__
     else:
@@ -201,7 +208,7 @@ def __init__(self, type, instance, schema):
         self.schema = schema
 
     def __unicode__(self):
-        pschema = json.dumps(self.schema, separators=(',\n', ': '), sort_keys=True)
+        pschema = pprint.pformat(self.schema, width=72)
         pinstance = pprint.pformat(self.instance, width=72)
         return textwrap.dedent("""
             Unknown type %r for validator with schema: