cros/commands/lint_unittest.py

#!/usr/bin/python
# Copyright (c) 2013 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""Test the lint module."""

import collections
import os
import sys

sys.path.insert(0, os.path.abspath('%s/../../..' % os.path.dirname(__file__)))

from chromite.lib import cros_test_lib
import lint


class TestNode(object):
  """Object good enough to stand in for lint funcs"""

  Args = collections.namedtuple('Args', ('args', 'vararg', 'kwarg'))

  def __init__(self, doc='', fromlineno=0, path='foo.py', args=(), vararg='',
               kwarg=''):
    self.doc = doc
    self.lines = doc.split('\n')
    self.fromlineno = fromlineno
    self.file = path
    self.args = self.Args(args=args, vararg=vararg, kwarg=kwarg)

  def argnames(self):
    return self.args


class DocStringCheckerTest(cros_test_lib.TestCase):
  """Tests for DocStringChecker module"""

  GOOD_FUNC_DOCSTRINGS = (
      'Some string',
      """Short summary

      Body of text.
      """,
      """line o text

      Body and comments on
      more than one line.

      Args:
        moo: cow

      Returns:
        some value

      Raises:
        something else
      """
  )

  BAD_FUNC_DOCSTRINGS = (
      """
      bad first line
      """,
      """ whitespace is wrong""",
      """whitespace is wrong	""",
      """Should be no trailing blank lines

      Returns:
        a value

      """
      """ok line

      cuddled end""",
      """we want Args/Returns not Arguments/Return

      Arguments:
      Return:
      """,
      """section order is wrong here

      Raises:
      Returns:
      """,
      """sections lack whitespace between them

      Args:
        foo: bar
      Returns:
        yeah
      """,
  )

  # The current linter isn't good enough yet to detect these.
  TODO_BAD_FUNC_DOCSTRINGS = (
      """The returns section isn't a proper section

      Args:
        bloop: de

      returns something
      """,
      """the indentation is incorrect

        Args:
          some: day
      """,
      """too many spaces after the colon

      Args:
        some:    day
      """,
  )

  def add_message(self, msg_id, node=None, line=None, args=None):
    """Capture lint checks"""
    # We include node.doc here explicitly so the pretty assert message
    # inclues it in the output automatically.
    self.results.append((msg_id, node.doc, line, args))

  def setUp(self):
    self.results = []
    self.checker = lint.DocStringChecker()
    self.checker.add_message = self.add_message

  def testGood_visit_function(self):
    """Allow known good docstrings"""
    for dc in self.GOOD_FUNC_DOCSTRINGS:
      self.results = []
      node = TestNode(doc=dc)
      self.checker.visit_function(node)
      self.assertEqual(self.results, [],
                       msg='docstring was not accepted:\n"""%s"""' % dc)

  def testBad_visit_function(self):
    """Reject known bad docstrings"""
    for dc in self.BAD_FUNC_DOCSTRINGS:
      self.results = []
      node = TestNode(doc=dc)
      self.checker.visit_function(node)
      self.assertNotEqual(self.results, [],
                          msg='docstring was not rejected:\n"""%s"""' % dc)

  def testSmoke_visit_module(self):
    """Smoke test for modules"""
    self.checker.visit_module(TestNode(doc='foo'))
    self.assertEqual(self.results, [])
    self.checker.visit_module(TestNode(doc='', path='/foo/__init__.py'))
    self.assertEqual(self.results, [])

  def testSmoke_visit_class(self):
    """Smoke test for classes"""
    self.checker.visit_class(TestNode(doc='bar'))

  def testGood_check_first_line(self):
    """Verify _check_first_line accepts good inputs"""
    # pylint: disable=W0212
    docstrings = (
        'Some string',
    )
    for dc in docstrings:
      self.results = []
      node = TestNode(doc=dc)
      self.checker._check_first_line(node, node.lines)
      self.assertEqual(self.results, [],
                       msg='docstring was not accepted:\n"""%s"""' % dc)

  def testBad_check_first_line(self):
    """Verify _check_first_line rejects bad inputs"""
    # pylint: disable=W0212
    docstrings = (
        '\nSome string\n',
    )
    for dc in docstrings:
      self.results = []
      node = TestNode(doc=dc)
      self.checker._check_first_line(node, node.lines)
      self.assertEqual(len(self.results), 1)


if __name__ == '__main__':
  cros_test_lib.main()