Restrict use of iteritems, iterkeys and itervalues

Enabled hacking checks to check dict.iteritems, dict.itervalues and
dict.iterkeys should not be used in the future and raise error while
running pep8 using tox.

Change-Id: I1239bb5c651d0193141d5bb830872caf172ec561

HACKING.rst

@@ -41,3 +41,12 @@ run --parallel` will run it in parallel (this is the default incantation tox
 uses.) More information about testr can be found at:
 http://wiki.openstack.org/testr
 
+
+Heat Specific Commandments
+--------------------------
+
+- [Heat301] Use LOG.warning() rather than LOG.warn().
+- [Heat302] Python 3: do not use dict.iteritems.
+- [Heat303] Python 3: do not use dict.iterkeys.
+- [Heat304] Python 3: do not use dict.itervalues.
+

heat/hacking/checks.py

@@ -13,17 +13,58 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
+import re
+
+
+"""
+Guidelines for writing new hacking checks
+
+- Use only for Heat specific tests. OpenStack general tests
+  should be submitted to the common 'hacking' module.
+- Pick numbers in the range H3xx. Find the current test with
+  the highest allocated number and then pick the next value.
+- Keep the test method code in the source file ordered based
+  on the Heat3xx value.
+- List the new rule in the top level HACKING.rst file
+- Add test cases for each new rule to heat/tests/test_hacking.py
+
+"""
+
 
 def no_log_warn(logical_line):
     """Disallow 'LOG.warn('
 
     https://bugs.launchpad.net/tempest/+bug/1508442
 
-    H001
+    Heat301
     """
     if logical_line.startswith('LOG.warn('):
-        yield(0, 'H001 Use LOG.warning() rather than LOG.warn()')
+        yield(0, 'Heat301 Use LOG.warning() rather than LOG.warn()')
+
+
+def check_python3_no_iteritems(logical_line):
+    msg = ("Heat302: Use dict.items() instead of dict.iteritems().")
+
+    if re.search(r".*\.iteritems\(\)", logical_line):
+        yield(0, msg)
+
+
+def check_python3_no_iterkeys(logical_line):
+    msg = ("Heat303: Use dict.keys() instead of dict.iterkeys().")
+
+    if re.search(r".*\.iterkeys\(\)", logical_line):
+        yield(0, msg)
+
+
+def check_python3_no_itervalues(logical_line):
+    msg = ("Heat304: Use dict.values() instead of dict.itervalues().")
+
+    if re.search(r".*\.itervalues\(\)", logical_line):
+        yield(0, msg)
 
 
 def factory(register):
     register(no_log_warn)
+    register(check_python3_no_iteritems)
+    register(check_python3_no_iterkeys)
+    register(check_python3_no_itervalues)

heat/tests/test_hacking.py

@@ -0,0 +1,48 @@
+#    Copyright 2016 NTT DATA.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from heat.hacking import checks
+from heat.tests import common
+
+
+class HackingTestCase(common.HeatTestCase):
+    def test_dict_iteritems(self):
+        self.assertEqual(1, len(list(checks.check_python3_no_iteritems(
+            "obj.iteritems()"))))
+
+        self.assertEqual(0, len(list(checks.check_python3_no_iteritems(
+            "obj.items()"))))
+
+        self.assertEqual(0, len(list(checks.check_python3_no_iteritems(
+            "six.iteritems(ob))"))))
+
+    def test_dict_iterkeys(self):
+        self.assertEqual(1, len(list(checks.check_python3_no_iterkeys(
+            "obj.iterkeys()"))))
+
+        self.assertEqual(0, len(list(checks.check_python3_no_iterkeys(
+            "obj.keys()"))))
+
+        self.assertEqual(0, len(list(checks.check_python3_no_iterkeys(
+            "six.iterkeys(ob))"))))
+
+    def test_dict_itervalues(self):
+        self.assertEqual(1, len(list(checks.check_python3_no_itervalues(
+            "obj.itervalues()"))))
+
+        self.assertEqual(0, len(list(checks.check_python3_no_itervalues(
+            "obj.values()"))))
+
+        self.assertEqual(0, len(list(checks.check_python3_no_itervalues(
+            "six.itervalues(ob))"))))