Improve debugging info from view_config decorator.

Grab a frame when instanciating view_config, rather than pulling info from
venusian's AttachInfo.  See discussion at
https://github.com/Pylons/pyramid/issues/3471

This fixes the build for Python 3.8.

2 files changed, 21 insertions, 8 deletions

diff --git a/src/pyramid/view.py b/src/pyramid/view.py
index 944ad93ea..524e06fb2 100644
--- a/src/pyramid/view.py
+++ b/src/pyramid/view.py
@@ -1,5 +1,6 @@
 import itertools
 import sys
+import inspect
 
 import venusian
 
@@ -216,6 +217,13 @@ class view_config(object):
             if settings.get('context') is None:
                 settings['context'] = settings['for_']
         self.__dict__.update(settings)
+        self._get_info()
+
+    def _get_info(self):
+        frame = sys._getframe(2)
+        frameinfo = inspect.getframeinfo(frame)
+        sourceline = frameinfo[3][0].strip()
+        self._info = frameinfo[0], frameinfo[1], frameinfo[2], sourceline
 
     def __call__(self, wrapped):
         settings = self.__dict__.copy()
@@ -237,14 +245,13 @@ class view_config(object):
             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
@@ -253,10 +260,12 @@ 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
diff --git a/tests/test_view.py b/tests/test_view.py
index de40df1d5..e182c28ad 100644
--- a/tests/test_view.py
+++ b/tests/test_view.py
@@ -507,7 +507,14 @@ class TestViewConfigDecorator(unittest.TestCase):
 
     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_context_trumps_for(self):
         decorator = self._makeOne(context='123', for_='456')
@@ -560,7 +567,6 @@ class TestViewConfigDecorator(unittest.TestCase):
         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()
@@ -580,7 +586,6 @@ class TestViewConfigDecorator(unittest.TestCase):
         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')
@@ -600,7 +605,6 @@ class TestViewConfigDecorator(unittest.TestCase):
         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')