Hacking checks for not using dict iteration calls

Add 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.

Trivial Fix

Change-Id: Id7f0c8b963cfd5739ed3e2ecec2c0feebc290af4

HACKING.rst

@@ -25,3 +25,6 @@ glance Specific Commandments
 - [G327] Prevent use of deprecated contextlib.nested
 - [G328] Must use a dict comprehension instead of a dict constructor with a sequence of key-value pairs
 - [G329] Python 3: Do not use xrange.
+- [G330] Python 3: do not use dict.iteritems.
+- [G331] Python 3: do not use dict.iterkeys.
+- [G332] Python 3: do not use dict.itervalues.

glance/hacking/checks.py

@@ -162,6 +162,27 @@ def check_python3_xrange(logical_line):
                  "large loops.")
 
 
+def check_python3_no_iteritems(logical_line):
+    msg = ("G330: Use six.iteritems() or dict.items() instead of "
+           "dict.iteritems().")
+    if re.search(r".*\.iteritems\(\)", logical_line):
+        yield(0, msg)
+
+
+def check_python3_no_iterkeys(logical_line):
+    msg = ("G331: Use six.iterkeys() or dict.keys() instead of "
+           "dict.iterkeys().")
+    if re.search(r".*\.iterkeys\(\)", logical_line):
+        yield(0, msg)
+
+
+def check_python3_no_itervalues(logical_line):
+    msg = ("G332: Use six.itervalues() or dict.values instead of "
+           "dict.itervalues().")
+    if re.search(r".*\.itervalues\(\)", logical_line):
+        yield(0, msg)
+
+
 def factory(register):
     register(assert_true_instance)
     register(assert_equal_type)
@@ -172,3 +193,6 @@ def factory(register):
     register(check_no_contextlib_nested)
     register(dict_constructor_with_list_copy)
     register(check_python3_xrange)
+    register(check_python3_no_iteritems)
+    register(check_python3_no_iterkeys)
+    register(check_python3_no_itervalues)

glance/tests/test_hacking.py

@@ -108,3 +108,33 @@ class HackingTestCase(utils.BaseTestCase):
         self.assertEqual(0, len(list(func('for i in range(10)'))))
         self.assertEqual(0, len(list(func('for i in six.moves.range(10)'))))
         self.assertEqual(0, len(list(func('testxrange(10)'))))
+
+    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(
+            "six.iteritems(obj)"))))
+
+        self.assertEqual(0, len(list(checks.check_python3_no_iteritems(
+            "obj.items()"))))
+
+    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(
+            "six.iterkeys(obj)"))))
+
+        self.assertEqual(0, len(list(checks.check_python3_no_iterkeys(
+            "obj.keys()"))))
+
+    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(
+            "six.itervalues(ob)"))))
+
+        self.assertEqual(0, len(list(checks.check_python3_no_itervalues(
+            "obj.values()"))))