Improve debugging info from view_config decorator

Backports #3483

CHANGES.rst

@@ -6,6 +6,8 @@
 - Fix docs build for Sphinx 2.0.
   See https://github.com/Pylons/pyramid/pull/3481
 
+- Improve debugging info from ``pyramid.view.view_config`` decorator.
+  See https://github.com/Pylons/pyramid/pull/3485
 
 1.10.2 (2019-01-30)
 ===================

docs/api/view.rst

@@ -14,8 +14,7 @@
   .. autoclass:: view_config
      :members:
 
-  .. autoclass:: view_defaults
-     :members:
+  .. autofunction:: view_defaults
 
   .. autoclass:: notfound_view_config
      :members:

src/pyramid/view.py

@@ -1,5 +1,6 @@
 import itertools
 import sys
+import inspect
 
 import venusian
 
@@ -218,6 +219,13 @@ def __init__(self, **settings):
             if settings.get('context') is None:
                 settings['context'] = settings['for_']
         self.__dict__.update(settings)
+        self._get_info()
+
+    def _get_info(self):
+        depth = self.__dict__.get('_depth', 0)
+        frameinfo = inspect.stack()[depth + 2]
+        sourceline = frameinfo[4][0].strip()
+        self._info = frameinfo[1], frameinfo[2], frameinfo[3], sourceline
 
     def __call__(self, wrapped):
         settings = self.__dict__.copy()
@@ -239,14 +247,13 @@ def callback(context, name, ob):
             if settings.get('attr') is None:
                 settings['attr'] = wrapped.__name__
 
-        settings['_info'] = info.codeinfo  # fbo "action_method"
         return wrapped
 
 
 bfg_view = view_config  # bw compat (forever)
 
 
-class view_defaults(view_config):
+def view_defaults(**settings):
     """ A class :term:`decorator` which, when applied to a class, will
     provide defaults for all view configurations that use the class.  This
     decorator accepts all the arguments accepted by
@@ -255,10 +262,12 @@ class view_defaults(view_config):
     See :ref:`view_defaults` for more information.
     """
 
-    def __call__(self, wrapped):
-        wrapped.__view_defaults__ = self.__dict__.copy()
+    def wrap(wrapped):
+        wrapped.__view_defaults__ = settings
         return wrapped
 
+    return wrap
+
 
 class AppendSlashNotFoundViewFactory(object):
     """ There can only be one :term:`Not Found view` in any

tests/test_view.py

@@ -508,7 +508,25 @@ def _makeOne(self, *arg, **kw):
 
     def test_create_defaults(self):
         decorator = self._makeOne()
-        self.assertEqual(decorator.__dict__, {})
+        self.assertEqual(list(decorator.__dict__.keys()), ['_info'])
+
+    def test_create_info(self):
+        target = self._getTargetClass()
+        decorator = target()
+        info = decorator._info
+        self.assertEqual(info[2], 'test_create_info')
+        self.assertEqual(info[3], 'decorator = target()')
+
+    def test_create_info_depth(self):
+        target = self._getTargetClass()
+
+        def make():
+            return target(_depth=1)
+
+        decorator = make()
+        info = decorator._info
+        self.assertEqual(info[2], 'test_create_info_depth')
+        self.assertEqual(info[3], 'decorator = make()')
 
     def test_create_context_trumps_for(self):
         decorator = self._makeOne(context='123', for_='456')
@@ -561,7 +579,6 @@ def foo():  # pragma: no cover
         self.assertEqual(len(settings[0]), 3)
         self.assertEqual(settings[0]['venusian'], venusian)
         self.assertEqual(settings[0]['view'], None)  # comes from call_venusian
-        self.assertEqual(settings[0]['_info'], 'codeinfo')
 
     def test_call_class(self):
         decorator = self._makeOne()
@@ -581,7 +598,6 @@ class foo(object):
         self.assertEqual(settings[0]['venusian'], venusian)
         self.assertEqual(settings[0]['view'], None)  # comes from call_venusian
         self.assertEqual(settings[0]['attr'], 'foo')
-        self.assertEqual(settings[0]['_info'], 'codeinfo')
 
     def test_call_class_attr_already_set(self):
         decorator = self._makeOne(attr='abc')
@@ -601,7 +617,6 @@ class foo(object):
         self.assertEqual(settings[0]['venusian'], venusian)
         self.assertEqual(settings[0]['view'], None)  # comes from call_venusian
         self.assertEqual(settings[0]['attr'], 'abc')
-        self.assertEqual(settings[0]['_info'], 'codeinfo')
 
     def test_stacking(self):
         decorator1 = self._makeOne(name='1')