Enable pylint in horizon

tests.py files are excluded from targets checked by pylint
because it takes longer and longer time to check them somehow.

pylint 2.2.x is supported only in Python 3 and we already switched
our pep8 basepython to python3, so pylint and astroid are installed
only for python3. This seems the easiest way to ensure py27 env works.

literal-comparison error in openstack_dashboard/api/nova.py
is also fixed in this commit as it is simple enough.

Change-Id: Ic8868a44b296dba457be721716ca6f9d37ad9369

.pylintrc

@@ -2,15 +2,106 @@
 [MASTER]
 # Add <file or directory> to the black list. It should be a base name, not a
 # path. You may set this option multiple times.
-ignore=test
+ignore=test,tests,tests.py,local_settings.py
 
 [Messages Control]
-# NOTE(justinsb): We might want to have a 2nd strict pylintrc in future
-# C0111: Don't require docstrings on every method
-# W0511: TODOs in code comments are fine.
-# W0142: *args and **kwargs are fine.
-# W0622: Redefining id is fine.
-disable=C0111,W0511,W0142,W0622
+disable=
+# "F" Fatal errors that prevent further processing
+# "I" Informational noise
+ locally-disabled,
+# "E" Error for important programming issues (likely bugs)
+ access-member-before-definition,
+ assignment-from-no-return,
+ bad-super-call,
+ import-error,
+ logging-too-few-args,
+ method-hidden,
+ misplaced-bare-raise,
+ no-member,
+ no-name-in-module,
+ not-an-iterable,
+ not-callable,
+ raising-non-exception,
+ redundant-keyword-arg,
+ undefined-all-variable,
+ unexpected-keyword-arg,
+# "W" Warnings for stylistic problems or minor programming issues
+ arguments-differ,
+ attribute-defined-outside-init,
+ bad-indentation,
+ broad-except,
+ cell-var-from-loop,
+ dangerous-default-value,
+ deprecated-method,  # TODO
+ exec-used,
+ fixme,
+ keyword-arg-before-vararg,  # TODO
+ logging-not-lazy,
+ pointless-string-statement,
+ protected-access,
+ raising-format-tuple,
+ redefined-builtin,
+ redefined-outer-name,
+ reimported,
+ signature-differs,
+ super-init-not-called,
+ undefined-loop-variable,
+ unidiomatic-typecheck,
+ unnecessary-pass,
+ unused-argument,
+ unused-import,
+ unused-wildcard-import,
+ useless-else-on-loop,
+ useless-super-delegation,
+ using-constant-test,
+ wildcard-import,
+# "C" Coding convention violations
+ abstract-method,
+ anomalous-backslash-in-string,
+ bad-builtin,
+ bad-continuation,
+ bad-mcs-classmethod-argument,
+ deprecated-lambda,
+ expression-not-assigned,
+ global-statement,
+ invalid-name,
+ len-as-condition,
+ line-too-long,
+ misplaced-comparison-constant,
+ missing-docstring,
+ no-method-argument,
+ superfluous-parens,
+ too-many-lines,
+ try-except-raise,
+ ungrouped-imports,
+ unused-variable,
+ wrong-import-order,  # TODO
+# "R" Refactor recommendations
+ chained-comparison,
+ comparison-with-itself,
+ consider-using-dict-comprehension,
+ consider-using-in,
+ consider-using-set-comprehension,
+ cyclic-import,  # TODO
+ duplicate-code,
+ inconsistent-return-statements,  # TODO
+ interface-not-implemented,
+ no-else-return,
+ no-self-use,
+ redefined-argument-from-local,
+ simplifiable-if-expression,
+ simplifiable-if-statement,
+ too-many-ancestors,
+ too-many-arguments,
+ too-many-branches,
+ too-many-function-args,
+ too-many-instance-attributes,
+ too-many-locals,
+ too-many-nested-blocks,
+ too-many-return-statements,
+ too-many-statements,
+ trailing-comma-tuple,
+ useless-object-inheritance
 
 [Basic]
 # Variable names can be 1 to 31 characters long, with lowercase and underscores
@@ -29,6 +120,10 @@ module-rgx=(([a-z_][a-z0-9_]*)|([A-Z][a-zA-Z0-9]+)|(keystone-[a-z0-9_-]+))$
 # Don't require docstrings on tests.
 no-docstring-rgx=((__.*__)|([tT]est.*)|setUp|tearDown)$
 
+[Format]
+# Maximum number of characters on a single line.
+max-line-length=80
+
 [Design]
 max-public-methods=100
 min-public-methods=0
@@ -40,3 +135,11 @@ max-args=6
 # you should avoid to define new builtins when possible.
 # _ is used by our localization
 additional-builtins=_
+
+[typecheck]
+# List of module names for which member attributes should not be checked
+ignored-modules=six.moves,_MovedItems
+
+[reports]
+# Tells whether to display a full report or only the messages
+reports=no

openstack_dashboard/api/nova.py

@@ -590,7 +590,7 @@ def server_list_paged(request,
         search_opts['project_id'] = request.user.tenant_id
 
     if search_opts.pop('paginate', False):
-        reversed_order = sort_dir is "asc"
+        reversed_order = sort_dir == "asc"
         LOG.debug("Notify received on deleted server: %r",
                   ('server_deleted' in request.session))
         deleted = request.session.pop('server_deleted',

test-requirements.txt

@@ -9,6 +9,7 @@
 # Hacking should appear first in case something else depends on pep8
 hacking>=1.1.0 # Apache-2.0
 #
+astroid==2.1.0;python_version>='3.0' # LGPLv2.1
 bandit>=1.4.0 # Apache-2.0
 coverage!=4.4,>=4.0 # Apache-2.0
 doc8>=0.6.0 # Apache-2.0
@@ -16,6 +17,7 @@ flake8-import-order==0.12 # LGPLv3
 mock>=2.0.0 # BSD
 mox3>=0.20.0 # Apache-2.0
 nodeenv>=0.9.4 # BSD
+pylint==2.2.2;python_version>='3.0' # GPLv2
 selenium>=2.50.1 # Apache-2.0
 testscenarios>=0.4 # Apache-2.0/BSD
 testtools>=2.2.0 # MIT

tox.ini

@@ -65,6 +65,7 @@ commands =
   {envpython} {toxinidir}/manage.py extract_messages --verbosity 0 --check-only
   bash {toxinidir}/tools/find_executables.sh
   doc8 doc/source releasenotes/source releasenotes/notes
+  pylint -j 4 --verbose --rcfile=.pylintrc -f colorized openstack_dashboard openstack_auth horizon
 
 [testenv:cover]
 basepython = python3