Fix ModelViewSet Nested bug (#65)

* Add todo repro app
* Add explicit test against model named "Nested"
* Force serializers named NestedSerializer to be output as inline models
* Allow ref_name to rescue a NestedSerializer
* Add tests and documentation

src/drf_yasg/inspectors/base.py

@@ -234,7 +234,8 @@ class FieldInspector(BaseInspector):
                     if default is not None:
                         instance_kwargs['default'] = default
 
-            instance_kwargs.setdefault('title', title)
+            if instance_kwargs.get('type', None) != openapi.TYPE_ARRAY:
+                instance_kwargs.setdefault('title', title)
             instance_kwargs.setdefault('description', description)
             instance_kwargs.update(kwargs)
 

src/drf_yasg/inspectors/field.py

@@ -1,3 +1,4 @@
+import logging
 import operator
 from collections import OrderedDict
 from decimal import Decimal
@@ -12,6 +13,8 @@ from ..errors import SwaggerGenerationError
 from ..utils import decimal_as_float, filter_none
 from .base import FieldInspector, NotHandled, SerializerInspector
 
+logger = logging.getLogger(__name__)
+
 
 class InlineSerializerInspector(SerializerInspector):
     """Provides serializer conversions using :meth:`.FieldInspector.field_to_swagger_object`."""
@@ -54,10 +57,14 @@ class InlineSerializerInspector(SerializerInspector):
 
             serializer = field
             serializer_meta = getattr(serializer, 'Meta', None)
+            serializer_name = type(serializer).__name__
             if hasattr(serializer_meta, 'ref_name'):
                 ref_name = serializer_meta.ref_name
+            elif serializer_name == 'NestedSerializer' and isinstance(serializer, serializers.ModelSerializer):
+                logger.debug("Forcing inline output for ModelSerializer named 'NestedSerializer': " + str(serializer))
+                ref_name = None
             else:
-                ref_name = type(serializer).__name__
+                ref_name = serializer_name
                 if ref_name.endswith('Serializer'):
                     ref_name = ref_name[:-len('Serializer')]
 
@@ -77,11 +84,17 @@ class InlineSerializerInspector(SerializerInspector):
                     if child.required:
                         required.append(property_name)
 
-                return SwaggerType(
+                result = SwaggerType(
                     type=openapi.TYPE_OBJECT,
                     properties=properties,
                     required=required or None,
                 )
+                if not ref_name:
+                    # on an inline model, the title is derived from the field name
+                    # but is visually displayed like the model named, which is confusing
+                    # it is better to just remove title from inline models
+                    del result.title
+                return result
 
             if not ref_name or not use_references:
                 return make_schema_definition()