Test with a context manager to create directory/file structure

gistfile1.py

import unittest
import os
import tempfile
import re
import shutil

from mock import patch

from reports import diskSpaceReport

TEMP_DIR = tempfile.gettempdir() + '/nightly/units'

@patch('files.DATA_DIR', tempfile.gettempdir())
class TestReports(unittest.TestCase):

    @classmethod
    def setUpClass(cls):
        # handle creation of master directory structure
        os.makedirs(TEMP_DIR)

    @classmethod
    def tearDownClass(cls):
        # remove all created directories and files
        shutil.rmtree(tempfile.gettempdir() + '/nightly')

    def test_disk_space_report(self):
        """
            disk space report should by default report mills that are over 80
            percent disk usage
        """
        data = [{"name": 3002,
                 "diskSpace-Unit3002": "Filesystem            Size  Used Avail Use%% Mounted on\n/dev/hda3             950M  804M  147M  85% /\n/dev/hda1             9.2M  2.6M  6.2M  30% /boot\ntmpfs                  61M  5.8M   55M  10% /dev/shm\n"},
                {"name": 3003,
                 "diskSpace-Unit3003": "Filesystem            Size  Used Avail Use%% Mounted on\n/dev/hda3             950M  804M  147M  75% /\n/dev/hda1             9.2M  2.6M  6.2M  30% /boot\ntmpfs                  61M  5.8M   55M  10% /dev/shm\n"}]
        with Mills(data):
            results = diskSpaceReport()

            self.assertEqual(len(results), 1)
            for result in results:
                self.assertEqual(result['mill'], '3002')

    def test_disk_space_report_custom(self):
        """
            disk space report should show only mills over a certain threshold
            of usage when passed show_usage_over=xx
        """
        data = [{"name": 3002,
                 "diskSpace-Unit3002": "Filesystem            Size  Used Avail Use%% Mounted on\n/dev/hda3             950M  804M  147M  85% /\n/dev/hda1             9.2M  2.6M  6.2M  30% /boot\ntmpfs                  61M  5.8M   55M  10% /dev/shm\n"},
                {"name": 3003,
                 "diskSpace-Unit3003": "Filesystem            Size  Used Avail Use%% Mounted on\n/dev/hda3             950M  804M  147M  50% /\n/dev/hda1             9.2M  2.6M  6.2M  30% /boot\ntmpfs                  61M  5.8M   55M  10% /dev/shm\n"}]
        with Mills(data):
            results = diskSpaceReport(show_usage_over=60)

            self.assertEqual(len(results), 1)
            for result in results:
                self.assertEqual(result['mill'], '3002')

    def test_disk_space_report_many_results(self):
        """
            disk space report should return a list of all mills that are
            over the threshold of disk usage
        """
        data = [{"name": 3002,
                 "diskSpace-Unit3002": "Filesystem            Size  Used Avail Use%% Mounted on\n/dev/hda3             950M  804M  147M  85% /\n/dev/hda1             9.2M  2.6M  6.2M  30% /boot\ntmpfs                  61M  5.8M   55M  10% /dev/shm\n"},
                {"name": 3003,
                 "diskSpace-Unit3003": "Filesystem            Size  Used Avail Use%% Mounted on\n/dev/hda3             950M  804M  147M  90% /\n/dev/hda1             9.2M  2.6M  6.2M  30% /boot\ntmpfs                  61M  5.8M   55M  10% /dev/shm\n"},
                {"name": 3004,
                 "diskSpace-Unit3003": "Filesystem            Size  Used Avail Use%% Mounted on\n/dev/hda3             950M  804M  147M  30% /\n/dev/hda1             9.2M  2.6M  6.2M  30% /boot\ntmpfs                  61M  5.8M   55M  10% /dev/shm\n"}]
        with Mills(data):
            results = diskSpaceReport()

            self.assertEqual(len(results), 2)
            for result in results:
                self.assertIn(result['mill'], ['3002', '3003'])


class Mills(object):
    """ context manager to create mill directory and files as needed for tests """
    def __init__(self, data):
        self.mill_dirs = []
        for mill in data:
            new_mill_dir = ''
            if 'name' in mill.keys():
                new_mill_dir = os.path.join(TEMP_DIR, str(mill['name']))
                os.makedirs(new_mill_dir)
                self.mill_dirs.append(new_mill_dir)
                mill.pop("name", None) # we are done with this key
            else:
                continue # invalid test data
            for key in mill:
                filename = os.path.join(new_mill_dir, key)
                f = open(filename, "w")
                f.write(mill[key])
                f.close()

    def __enter__(self):
        pass

    def __exit__(self, *args):
        """ remove all mill directories related to this context """
        for mill in self.mill_dirs:
            shutil.rmtree(mill)

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

removed chdir mumbo jumbo

and now its an actual test!

Added more tests to check scailability. Seems good.

So Mills is a Mock class?