#! /usr/bin/env python
"""Test script for the gdbm module
   Roger E. Masse
"""

import gdbm
import unittest
import os
from test.test_support import verbose, TESTFN, run_unittest, unlink


filename = TESTFN

class TestGdbm(unittest.TestCase):
    
    def setUp(self):
        self.g = None
    
    def tearDown(self):
        if self.g is not None:
            self.g.close()
        unlink(filename)
    
    def test_key_methods(self):
        self.g = gdbm.open(filename, 'c')
        self.assertEqual(self.g.keys(), [])
        self.g['a'] = 'b'
        self.g['12345678910'] = '019237410982340912840198242'        
        self.assertEqual(self.g.keys(), ['a', '12345678910'])
        self.assert_(self.g.has_key('a'))
        self.assertEqual(self.g.firstkey(), 'a')
        self.assertEqual(self.g.nextkey('a'), '12345678910')
        self.assertEqual(self.g.nextkey('12345678910'), None)
        self.assertRaises(KeyError, lambda: self.g['xxx'])

    def test_error_conditions(self):
        # try open a non existing database
        unlink(filename)
        self.assertRaises(gdbm.error, gdbm.open, filename, 'r')
        self.assertRaises(gdbm.error, gdbm.open, filename, 'w')
        # try access a closed database
        self.g = gdbm.open(filename, 'c')
        self.g.close()
        self.assertRaises(gdbm.error, lambda: self.g['a'])
        # try pass an invalid open flag
        self.assertRaises(gdbm.error, lambda: gdbm.open(filename, 'rx').close())

    def test_flags(self):
        # test flag clause in the open statement by trying all
        # supported mode flags
        all = set(gdbm.open_flags)
        # test standard flags (presumably "crwn")
        modes = all - set('fsu')
        for mode in modes:
            self.g = gdbm.open(filename, mode)
            self.g.close()

        # test additional flags (presumably "fsu")
        flags = all - set('crwn')
        for mode in modes:
            for flag in flags:
                self.g = gdbm.open(filename, mode + flag)
                self.g.close()

    def test_reorganize(self):
        self.g = gdbm.open(filename, 'c')
        size0 = os.path.getsize(filename)

        self.g['x'] = 'x' * 10000
        size1 = os.path.getsize(filename)
        self.assert_(size0 < size1)

        del self.g['x']
        # size is supposed to be the same also after deleting the entry
        self.assertEqual(os.path.getsize(filename), size1)
     
        self.g.reorganize()
        size2 = os.path.getsize(filename)
        self.assert_(size1 > size2 >= size0)


def test_main():
    run_unittest(TestGdbm)
    
if __name__ == '__main__':
    test_main()