Added checking for no expected warning

Details:

* So far, when a testcase using 'simplified_test_function' did not specify
  expected warnings, warnings that occurred were tolerated..
  This change fixes that by raising an AssertionError in that case.

* Adjusted a testcase to accomodate the new check.

Signed-off-by: Andreas Maier <andreas.r.maier@gmx.de>

docs/changes.rst

@@ -23,6 +23,9 @@ Released: not yet
 
 **Enhancements:**
 
+* Added checking for no expected warning. Adjusted a testcase to accomodate
+  the new check. (see issue #65)
+
 **Cleanup:**
 
 **Known issues:**

tests/unittest/test_nocasedict.py

@@ -46,8 +46,9 @@
 TESTDICT_SUPPORTS_COMPARISON = \
     TEST_AGAINST_DICT and sys.version_info[0:2] == (2, 7)
 
-# Indicates the dict being tested issues UserWarning about unordered kwargs
-TESTDICT_WARNS_KWARGS = \
+# Indicates the dict being tested issues UserWarning about not preserving order
+# of items in kwargs or in standard dict
+TESTDICT_WARNS_ORDER = \
     not TEST_AGAINST_DICT and sys.version_info[0:2] < (3, 7)
 
 # Indicates the dict supports the iter..() and view..() methods
@@ -177,7 +178,7 @@ def __ne__(self, other):
             exp_dict=OrderedDict([('Dog', 'Cat'), ('Budgie', 'Fish')]),
             verify_order=False,
         ),
-        None, None, True
+        None, UserWarning if TESTDICT_WARNS_ORDER else None, True
     ),
     (
         "Dict from keyword args",
@@ -187,7 +188,7 @@ def __ne__(self, other):
             exp_dict=OrderedDict([('Dog', 'Cat'), ('Budgie', 'Fish')]),
             verify_order=False,
         ),
-        None, UserWarning if TESTDICT_WARNS_KWARGS else None, True
+        None, UserWarning if TESTDICT_WARNS_ORDER else None, True
     ),
     (
         "Dict from list as positional arg and keyword args",

tests/utils/simplified_test_function.py

@@ -149,21 +149,35 @@ def wrapper_func(desc, kwargs, exp_exc_types, exp_warn_types, condition):
                     ret = None  # Debugging hint
                     assert len(rec_warnings) >= 1
         else:
-            if exp_exc_types:
-                with pytest.raises(exp_exc_types):
+            with pytest.warns(None) as rec_warnings:
+                if exp_exc_types:
+                    with pytest.raises(exp_exc_types):
+                        if condition == 'pdb':
+                            pdb.set_trace()
+
+                        test_func(testcase, **kwargs)  # expecting an exception
+
+                    ret = None  # Debugging hint
+                else:
                     if condition == 'pdb':
                         pdb.set_trace()
 
-                    test_func(testcase, **kwargs)  # expecting an exception
-
-                ret = None  # Debugging hint
-            else:
-                if condition == 'pdb':
-                    pdb.set_trace()
+                    test_func(testcase, **kwargs)  # not expecting an exception
 
-                test_func(testcase, **kwargs)  # not expecting an exception
+                    ret = None  # Debugging hint
 
-                ret = None  # Debugging hint
+                    # Verify that no warnings have occurred
+                    if exp_warn_types is None and rec_warnings:
+                        lines = []
+                        for w in rec_warnings.list:
+                            tup = (w.filename, w.lineno, w.category.__name__,
+                                   str(w.message))
+                            line = "{t[0]}:{t[1]}: {t[2]}: {t[3]}".format(t=tup)
+                            if line not in lines:
+                                lines.append(line)
+                        msg = "Unexpected warnings:\n{}".format(
+                            '\n'.join(lines))
+                        raise AssertionError(msg)
         return ret
 
     # Needed because the decorator is signature-changin