Fix a bug that broke `default_renderer = json`.

Change-Id: Ie57feadb6efe664c1bc3c39debcb21c3355f210c
Fixes bug 1332501

2 files changed, 16 insertions, 1 deletions

diff --git a/pecan/core.py b/pecan/core.py
index 44bad0e..eb3fe69 100644
--- a/pecan/core.py
+++ b/pecan/core.py
@@ -526,7 +526,9 @@ class PecanBase(object):
         template = content_types.get(pecan_state['content_type'])
 
         # check if for controller override of template
-        template = pecan_state.get('override_template', template)
+        template = pecan_state.get('override_template', template) or (
+            'json' if self.default_renderer == 'json' else None
+        )
         pecan_state['content_type'] = pecan_state.get(
             'override_content_type',
             pecan_state['content_type']
diff --git a/pecan/tests/test_base.py b/pecan/tests/test_base.py
index 81471ec..c076139 100644
--- a/pecan/tests/test_base.py
+++ b/pecan/tests/test_base.py
@@ -1520,6 +1520,19 @@ class TestEngines(PecanTestCase):
         assert r.status_int == 200
         assert b_("<h1>Hello, Jonathan!</h1>") in r.body
 
+    def test_default_json_renderer(self):
+
+        class RootController(object):
+            @expose()
+            def index(self, name='Bill'):
+                return dict(name=name)
+
+        app = TestApp(Pecan(RootController(), default_renderer='json'))
+        r = app.get('/')
+        assert r.status_int == 200
+        result = dict(json.loads(r.body.decode()))
+        assert result == {'name': 'Bill'}
+
 
 class TestDeprecatedRouteMethod(PecanTestCase):