`deprecated_call` detects pending warnings again

`deprecated_call` now looks for PendingDeprecationWarnings,
as it did previously but was broken by #897. Fixes #1037.

Also added a test so this does not happen again.

_pytest/recwarn.py

@@ -36,7 +36,8 @@ def deprecated_call(func, *args, **kwargs):
         warnings.simplefilter('always')  # ensure all warnings are triggered
         ret = func(*args, **kwargs)
 
-    if not any(r.category is DeprecationWarning for r in wrec):
+    depwarnings = (DeprecationWarning, PendingDeprecationWarning)
+    if not any(r.category in depwarnings for r in wrec):
         __tracebackhide__ = True
         raise AssertionError("%r did not produce DeprecationWarning" % (func,))
 

testing/test_recwarn.py

@@ -111,6 +111,10 @@ class TestDeprecatedCall(object):
         pytest.deprecated_call(dep_explicit, 0)
         pytest.deprecated_call(dep_explicit, 0)
 
+    def test_deprecated_call_pending(self):
+        f = lambda: py.std.warnings.warn(PendingDeprecationWarning("hi"))
+        pytest.deprecated_call(f)
+
 
 class TestWarns(object):
     def test_strings(self):
@@ -181,4 +185,3 @@ class TestWarns(object):
         ''')
         result = testdir.runpytest()
         result.stdout.fnmatch_lines(['*2 passed in*'])
-