Lib/test/test_csv.py

   1 # Copyright (C) 2001,2002 Python Software Foundation
   2 # csv package unit tests
   3
   4 import sys
   5 import unittest
   6 from StringIO import StringIO
   7 import csv
   8 import gc
   9 from test.test_support import verbose
  10
  11 class Test_Csv(unittest.TestCase):
  12     """
  13     Test the underlying C csv parser in ways that are not appropriate
  14     from the high level interface. Further tests of this nature are done
  15     in TestDialectRegistry.
  16     """
  17     def test_reader_arg_valid(self):
  18         self.assertRaises(TypeError, csv.reader)
  19         self.assertRaises(TypeError, csv.reader, None)
  20         self.assertRaises(AttributeError, csv.reader, [], bad_attr = 0)
  21         self.assertRaises(csv.Error, csv.reader, [], 'foo')
  22         class BadClass:
  23             def __init__(self):
  24                 raise IOError
  25         self.assertRaises(IOError, csv.reader, [], BadClass)
  26         self.assertRaises(TypeError, csv.reader, [], None)
  27         class BadDialect:
  28             bad_attr = 0
  29         self.assertRaises(AttributeError, csv.reader, [], BadDialect)
  30
  31     def test_writer_arg_valid(self):
  32         self.assertRaises(TypeError, csv.writer)
  33         self.assertRaises(TypeError, csv.writer, None)
  34         self.assertRaises(AttributeError, csv.writer, StringIO(), bad_attr = 0)
  35
  36     def _test_attrs(self, obj):
  37         self.assertEqual(obj.dialect.delimiter, ',')
  38         obj.dialect.delimiter = '\t'
  39         self.assertEqual(obj.dialect.delimiter, '\t')
  40         self.assertRaises(TypeError, delattr, obj.dialect, 'delimiter')
  41         self.assertRaises(TypeError, setattr, obj.dialect,
  42                           'lineterminator', None)
  43         obj.dialect.escapechar = None
  44         self.assertEqual(obj.dialect.escapechar, None)
  45         self.assertRaises(TypeError, delattr, obj.dialect, 'quoting')
  46         self.assertRaises(TypeError, setattr, obj.dialect, 'quoting', None)
  47         obj.dialect.quoting = csv.QUOTE_MINIMAL
  48         self.assertEqual(obj.dialect.quoting, csv.QUOTE_MINIMAL)
  49
  50     def test_reader_attrs(self):
  51         self._test_attrs(csv.reader([]))
  52
  53     def test_writer_attrs(self):
  54         self._test_attrs(csv.writer(StringIO()))
  55
  56     def _write_test(self, fields, expect, **kwargs):
  57         fileobj = StringIO()
  58         writer = csv.writer(fileobj, **kwargs)
  59         writer.writerow(fields)
  60         self.assertEqual(fileobj.getvalue(),
  61                          expect + writer.dialect.lineterminator)
  62
  63     def test_write_arg_valid(self):
  64         self.assertRaises(csv.Error, self._write_test, None, '')
  65         self._write_test((), '')
  66         self._write_test([None], '""')
  67         self.assertRaises(csv.Error, self._write_test,
  68                           [None], None, quoting = csv.QUOTE_NONE)
  69         # Check that exceptions are passed up the chain
  70         class BadList:
  71             def __len__(self):
  72                 return 10;
  73             def __getitem__(self, i):
  74                 if i > 2:
  75                     raise IOError
  76         self.assertRaises(IOError, self._write_test, BadList(), '')
  77         class BadItem:
  78             def __str__(self):
  79                 raise IOError
  80         self.assertRaises(IOError, self._write_test, [BadItem()], '')
  81
  82     def test_write_bigfield(self):
  83         # This exercises the buffer realloc functionality
  84         bigstring = 'X' * 50000
  85         self._write_test([bigstring,bigstring], '%s,%s' % \
  86                          (bigstring, bigstring))
  87
  88     def test_write_quoting(self):
  89         self._write_test(['a','1','p,q'], 'a,1,"p,q"')
  90         self.assertRaises(csv.Error,
  91                           self._write_test,
  92                           ['a','1','p,q'], 'a,1,"p,q"',
  93                           quoting = csv.QUOTE_NONE)
  94         self._write_test(['a','1','p,q'], 'a,1,"p,q"',
  95                          quoting = csv.QUOTE_MINIMAL)
  96         self._write_test(['a','1','p,q'], '"a",1,"p,q"',
  97                          quoting = csv.QUOTE_NONNUMERIC)
  98         self._write_test(['a','1','p,q'], '"a","1","p,q"',
  99                          quoting = csv.QUOTE_ALL)
 100
 101     def test_write_escape(self):
 102         self._write_test(['a','1','p,q'], 'a,1,"p,q"',
 103                          escapechar='\\')
 104 # FAILED - needs to be fixed [am]:
 105 #        self._write_test(['a','1','p,"q"'], 'a,1,"p,\\"q\\"',
 106 #                         escapechar='\\', doublequote = 0)
 107         self._write_test(['a','1','p,q'], 'a,1,p\\,q',
 108                          escapechar='\\', quoting = csv.QUOTE_NONE)
 109
 110     def test_writerows(self):
 111         class BrokenFile:
 112             def write(self, buf):
 113                 raise IOError
 114         writer = csv.writer(BrokenFile())
 115         self.assertRaises(IOError, writer.writerows, [['a']])
 116         fileobj = StringIO()
 117         writer = csv.writer(fileobj)
 118         self.assertRaises(TypeError, writer.writerows, None)
 119         writer.writerows([['a','b'],['c','d']])
 120         self.assertEqual(fileobj.getvalue(), "a,b\r\nc,d\r\n")
 121
 122     def _read_test(self, input, expect, **kwargs):
 123         reader = csv.reader(input, **kwargs)
 124         result = list(reader)
 125         self.assertEqual(result, expect)
 126
 127     def test_read_oddinputs(self):
 128         self._read_test([], [])
 129         self._read_test([''], [[]])
 130         self.assertRaises(csv.Error, self._read_test,
 131                           ['"ab"c'], None, strict = 1)
 132         # cannot handle null bytes for the moment
 133         self.assertRaises(csv.Error, self._read_test,
 134                           ['ab\0c'], None, strict = 1)
 135         self._read_test(['"ab"c'], [['abc']], doublequote = 0)
 136
 137     def test_read_eol(self):
 138         self._read_test(['a,b'], [['a','b']])
 139         self._read_test(['a,b\n'], [['a','b']])
 140         self._read_test(['a,b\r\n'], [['a','b']])
 141         self._read_test(['a,b\r'], [['a','b']])
 142         self.assertRaises(csv.Error, self._read_test, ['a,b\rc,d'], [])
 143         self.assertRaises(csv.Error, self._read_test, ['a,b\nc,d'], [])
 144         self.assertRaises(csv.Error, self._read_test, ['a,b\r\nc,d'], [])
 145
 146     def test_read_escape(self):
 147         self._read_test(['a,\\b,c'], [['a', '\\b', 'c']], escapechar='\\')
 148         self._read_test(['a,b\\,c'], [['a', 'b,c']], escapechar='\\')
 149         self._read_test(['a,"b\\,c"'], [['a', 'b,c']], escapechar='\\')
 150         self._read_test(['a,"b,\\c"'], [['a', 'b,\\c']], escapechar='\\')
 151         self._read_test(['a,"b,c\\""'], [['a', 'b,c"']], escapechar='\\')
 152         self._read_test(['a,"b,c"\\'], [['a', 'b,c\\']], escapechar='\\')
 153
 154     def test_read_bigfield(self):
 155         # This exercises the buffer realloc functionality
 156         bigstring = 'X' * 50000
 157         bigline = '%s,%s' % (bigstring, bigstring)
 158         self._read_test([bigline], [[bigstring, bigstring]])
 159
 160 class TestDialectRegistry(unittest.TestCase):
 161     def test_registry_badargs(self):
 162         self.assertRaises(TypeError, csv.list_dialects, None)
 163         self.assertRaises(TypeError, csv.get_dialect)
 164         self.assertRaises(csv.Error, csv.get_dialect, None)
 165         self.assertRaises(csv.Error, csv.get_dialect, "nonesuch")
 166         self.assertRaises(TypeError, csv.unregister_dialect)
 167         self.assertRaises(csv.Error, csv.unregister_dialect, None)
 168         self.assertRaises(csv.Error, csv.unregister_dialect, "nonesuch")
 169         self.assertRaises(TypeError, csv.register_dialect, None)
 170         self.assertRaises(TypeError, csv.register_dialect, None, None)
 171         self.assertRaises(TypeError, csv.register_dialect, "nonesuch", None)
 172         class bogus:
 173             def __init__(self):
 174                 raise KeyError
 175         self.assertRaises(KeyError, csv.register_dialect, "nonesuch", bogus)
 176
 177     def test_registry(self):
 178         class myexceltsv(csv.excel):
 179             delimiter = "\t"
 180         name = "myexceltsv"
 181         expected_dialects = csv.list_dialects() + [name]
 182         expected_dialects.sort()
 183         csv.register_dialect(name, myexceltsv)
 184         try:
 185             self.failUnless(isinstance(csv.get_dialect(name), myexceltsv))
 186             got_dialects = csv.list_dialects()
 187             got_dialects.sort()
 188             self.assertEqual(expected_dialects, got_dialects)
 189         finally:
 190             csv.unregister_dialect(name)
 191
 192     def test_incomplete_dialect(self):
 193         class myexceltsv(csv.Dialect):
 194             delimiter = "\t"
 195         self.assertRaises(csv.Error, myexceltsv)
 196
 197     def test_space_dialect(self):
 198         class space(csv.excel):
 199             delimiter = " "
 200             quoting = csv.QUOTE_NONE
 201             escapechar = "\\"
 202
 203         s = StringIO("abc def\nc1ccccc1 benzene\n")
 204         rdr = csv.reader(s, dialect=space())
 205         self.assertEqual(rdr.next(), ["abc", "def"])
 206         self.assertEqual(rdr.next(), ["c1ccccc1", "benzene"])
 207
 208     def test_dialect_apply(self):
 209         class testA(csv.excel):
 210             delimiter = "\t"
 211         class testB(csv.excel):
 212             delimiter = ":"
 213         class testC(csv.excel):
 214             delimiter = "|"
 215
 216         csv.register_dialect('testC', testC)
 217         try:
 218             fileobj = StringIO()
 219             writer = csv.writer(fileobj)
 220             writer.writerow([1,2,3])
 221             self.assertEqual(fileobj.getvalue(), "1,2,3\r\n")
 222
 223             fileobj = StringIO()
 224             writer = csv.writer(fileobj, testA)
 225             writer.writerow([1,2,3])
 226             self.assertEqual(fileobj.getvalue(), "1\t2\t3\r\n")
 227
 228             fileobj = StringIO()
 229             writer = csv.writer(fileobj, dialect=testB())
 230             writer.writerow([1,2,3])
 231             self.assertEqual(fileobj.getvalue(), "1:2:3\r\n")
 232
 233             fileobj = StringIO()
 234             writer = csv.writer(fileobj, dialect='testC')
 235             writer.writerow([1,2,3])
 236             self.assertEqual(fileobj.getvalue(), "1|2|3\r\n")
 237
 238             fileobj = StringIO()
 239             writer = csv.writer(fileobj, dialect=testA, delimiter=';')
 240             writer.writerow([1,2,3])
 241             self.assertEqual(fileobj.getvalue(), "1;2;3\r\n")
 242         finally:
 243             csv.unregister_dialect('testC')
 244
 245     def test_bad_dialect(self):
 246         # Unknown parameter
 247         self.assertRaises(AttributeError, csv.reader, [], bad_attr = 0)
 248         # Bad values
 249         self.assertRaises(TypeError, csv.reader, [], delimiter = None)
 250         self.assertRaises(TypeError, csv.reader, [], quoting = -1)
 251         self.assertRaises(TypeError, csv.reader, [], quoting = 100)
 252
 253 class TestCsvBase(unittest.TestCase):
 254     def readerAssertEqual(self, input, expected_result):
 255         reader = csv.reader(StringIO(input), dialect = self.dialect)
 256         fields = list(reader)
 257         self.assertEqual(fields, expected_result)
 258
 259     def writerAssertEqual(self, input, expected_result):
 260         fileobj = StringIO()
 261         writer = csv.writer(fileobj, dialect = self.dialect)
 262         writer.writerows(input)
 263         self.assertEqual(fileobj.getvalue(), expected_result)
 264
 265 class TestDialectExcel(TestCsvBase):
 266     dialect = 'excel'
 267
 268     def test_single(self):
 269         self.readerAssertEqual('abc', [['abc']])
 270
 271     def test_simple(self):
 272         self.readerAssertEqual('1,2,3,4,5', [['1','2','3','4','5']])
 273
 274     def test_blankline(self):
 275         self.readerAssertEqual('', [])
 276
 277     def test_empty_fields(self):
 278         self.readerAssertEqual(',', [['', '']])
 279
 280     def test_singlequoted(self):
 281         self.readerAssertEqual('""', [['']])
 282
 283     def test_singlequoted_left_empty(self):
 284         self.readerAssertEqual('"",', [['','']])
 285
 286     def test_singlequoted_right_empty(self):
 287         self.readerAssertEqual(',""', [['','']])
 288
 289     def test_single_quoted_quote(self):
 290         self.readerAssertEqual('""""', [['"']])
 291
 292     def test_quoted_quotes(self):
 293         self.readerAssertEqual('""""""', [['""']])
 294
 295     def test_inline_quote(self):
 296         self.readerAssertEqual('a""b', [['a""b']])
 297
 298     def test_inline_quotes(self):
 299         self.readerAssertEqual('a"b"c', [['a"b"c']])
 300
 301     def test_quotes_and_more(self):
 302         self.readerAssertEqual('"a"b', [['ab']])
 303
 304     def test_lone_quote(self):
 305         self.readerAssertEqual('a"b', [['a"b']])
 306
 307     def test_quote_and_quote(self):
 308         self.readerAssertEqual('"a" "b"', [['a "b"']])
 309
 310     def test_space_and_quote(self):
 311         self.readerAssertEqual(' "a"', [[' "a"']])
 312
 313     def test_quoted(self):
 314         self.readerAssertEqual('1,2,3,"I think, therefore I am",5,6',
 315                                [['1', '2', '3',
 316                                  'I think, therefore I am',
 317                                  '5', '6']])
 318
 319     def test_quoted_quote(self):
 320         self.readerAssertEqual('1,2,3,"""I see,"" said the blind man","as he picked up his hammer and saw"',
 321                                [['1', '2', '3',
 322                                  '"I see," said the blind man',
 323                                  'as he picked up his hammer and saw']])
 324
 325     def test_quoted_nl(self):
 326         input = '''\
 327 1,2,3,"""I see,""
 328 said the blind man","as he picked up his
 329 hammer and saw"
 330 9,8,7,6'''
 331         self.readerAssertEqual(input,
 332                                [['1', '2', '3',
 333                                    '"I see,"\nsaid the blind man',
 334                                    'as he picked up his\nhammer and saw'],
 335                                 ['9','8','7','6']])
 336
 337     def test_dubious_quote(self):
 338         self.readerAssertEqual('12,12,1",', [['12', '12', '1"', '']])
 339
 340     def test_null(self):
 341         self.writerAssertEqual([], '')
 342
 343     def test_single(self):
 344         self.writerAssertEqual([['abc']], 'abc\r\n')
 345
 346     def test_simple(self):
 347         self.writerAssertEqual([[1, 2, 'abc', 3, 4]], '1,2,abc,3,4\r\n')
 348
 349     def test_quotes(self):
 350         self.writerAssertEqual([[1, 2, 'a"bc"', 3, 4]], '1,2,"a""bc""",3,4\r\n')
 351
 352     def test_quote_fieldsep(self):
 353         self.writerAssertEqual([['abc,def']], '"abc,def"\r\n')
 354
 355     def test_newlines(self):
 356         self.writerAssertEqual([[1, 2, 'a\nbc', 3, 4]], '1,2,"a\nbc",3,4\r\n')
 357
 358 class EscapedExcel(csv.excel):
 359     quoting = csv.QUOTE_NONE
 360     escapechar = '\\'
 361
 362 class TestEscapedExcel(TestCsvBase):
 363     dialect = EscapedExcel()
 364
 365     def test_escape_fieldsep(self):
 366         self.writerAssertEqual([['abc,def']], 'abc\\,def\r\n')
 367
 368     def test_read_escape_fieldsep(self):
 369         self.readerAssertEqual('abc\\,def\r\n', [['abc,def']])
 370
 371 class QuotedEscapedExcel(csv.excel):
 372     quoting = csv.QUOTE_NONNUMERIC
 373     escapechar = '\\'
 374
 375 class TestQuotedEscapedExcel(TestCsvBase):
 376     dialect = QuotedEscapedExcel()
 377
 378     def test_write_escape_fieldsep(self):
 379         self.writerAssertEqual([['abc,def']], '"abc,def"\r\n')
 380
 381     def test_read_escape_fieldsep(self):
 382         self.readerAssertEqual('"abc\\,def"\r\n', [['abc,def']])
 383
 384 # Disabled, pending support in csv.utils module
 385 class TestDictFields(unittest.TestCase):
 386     ### "long" means the row is longer than the number of fieldnames
 387     ### "short" means there are fewer elements in the row than fieldnames
 388     def test_write_simple_dict(self):
 389         fileobj = StringIO()
 390         writer = csv.DictWriter(fileobj, fieldnames = ["f1", "f2", "f3"])
 391         writer.writerow({"f1": 10, "f3": "abc"})
 392         self.assertEqual(fileobj.getvalue(), "10,,abc\r\n")
 393
 394     def test_write_no_fields(self):
 395         fileobj = StringIO()
 396         self.assertRaises(TypeError, csv.DictWriter, fileobj)
 397
 398     def test_read_dict_fields(self):
 399         reader = csv.DictReader(StringIO("1,2,abc\r\n"),
 400                                 fieldnames=["f1", "f2", "f3"])
 401         self.assertEqual(reader.next(), {"f1": '1', "f2": '2', "f3": 'abc'})
 402
 403     def test_read_long(self):
 404         reader = csv.DictReader(StringIO("1,2,abc,4,5,6\r\n"),
 405                                 fieldnames=["f1", "f2"])
 406         self.assertEqual(reader.next(), {"f1": '1', "f2": '2',
 407                                          None: ["abc", "4", "5", "6"]})
 408
 409     def test_read_long_with_rest(self):
 410         reader = csv.DictReader(StringIO("1,2,abc,4,5,6\r\n"),
 411                                 fieldnames=["f1", "f2"], restkey="_rest")
 412         self.assertEqual(reader.next(), {"f1": '1', "f2": '2',
 413                                          "_rest": ["abc", "4", "5", "6"]})
 414
 415     def test_read_short(self):
 416         reader = csv.DictReader(["1,2,abc,4,5,6\r\n","1,2,abc\r\n"],
 417                                 fieldnames="1 2 3 4 5 6".split(),
 418                                 restval="DEFAULT")
 419         self.assertEqual(reader.next(), {"1": '1', "2": '2', "3": 'abc',
 420                                          "4": '4', "5": '5', "6": '6'})
 421         self.assertEqual(reader.next(), {"1": '1', "2": '2', "3": 'abc',
 422                                          "4": 'DEFAULT', "5": 'DEFAULT',
 423                                          "6": 'DEFAULT'})
 424
 425     def test_read_with_blanks(self):
 426         reader = csv.DictReader(["1,2,abc,4,5,6\r\n","\r\n",
 427                                  "1,2,abc,4,5,6\r\n"],
 428                                 fieldnames="1 2 3 4 5 6".split())
 429         self.assertEqual(reader.next(), {"1": '1', "2": '2', "3": 'abc',
 430                                          "4": '4', "5": '5', "6": '6'})
 431         self.assertEqual(reader.next(), {"1": '1', "2": '2', "3": 'abc',
 432                                          "4": '4', "5": '5', "6": '6'})
 433
 434 class TestArrayWrites(unittest.TestCase):
 435     def test_int_write(self):
 436         import array
 437         contents = [(20-i) for i in range(20)]
 438         a = array.array('i', contents)
 439         fileobj = StringIO()
 440         writer = csv.writer(fileobj, dialect="excel")
 441         writer.writerow(a)
 442         expected = ",".join([str(i) for i in a])+"\r\n"
 443         self.assertEqual(fileobj.getvalue(), expected)
 444
 445     def test_double_write(self):
 446         import array
 447         contents = [(20-i)*0.1 for i in range(20)]
 448         a = array.array('d', contents)
 449         fileobj = StringIO()
 450         writer = csv.writer(fileobj, dialect="excel")
 451         writer.writerow(a)
 452         expected = ",".join([str(i) for i in a])+"\r\n"
 453         self.assertEqual(fileobj.getvalue(), expected)
 454
 455     def test_float_write(self):
 456         import array
 457         contents = [(20-i)*0.1 for i in range(20)]
 458         a = array.array('f', contents)
 459         fileobj = StringIO()
 460         writer = csv.writer(fileobj, dialect="excel")
 461         writer.writerow(a)
 462         expected = ",".join([str(i) for i in a])+"\r\n"
 463         self.assertEqual(fileobj.getvalue(), expected)
 464
 465     def test_char_write(self):
 466         import array, string
 467         a = array.array('c', string.letters)
 468         fileobj = StringIO()
 469         writer = csv.writer(fileobj, dialect="excel")
 470         writer.writerow(a)
 471         expected = ",".join(a)+"\r\n"
 472         self.assertEqual(fileobj.getvalue(), expected)
 473
 474 class TestDialectValidity(unittest.TestCase):
 475     def test_quoting(self):
 476         class mydialect(csv.Dialect):
 477             delimiter = ";"
 478             escapechar = '\\'
 479             doublequote = False
 480             skipinitialspace = True
 481             lineterminator = '\r\n'
 482             quoting = csv.QUOTE_NONE
 483         d = mydialect()
 484
 485         mydialect.quoting = None
 486         self.assertRaises(csv.Error, mydialect)
 487
 488         mydialect.quoting = csv.QUOTE_NONE
 489         mydialect.escapechar = None
 490         self.assertRaises(csv.Error, mydialect)
 491
 492         mydialect.doublequote = True
 493         mydialect.quoting = csv.QUOTE_ALL
 494         mydialect.quotechar = '"'
 495         d = mydialect()
 496
 497         mydialect.quotechar = "''"
 498         self.assertRaises(csv.Error, mydialect)
 499
 500         mydialect.quotechar = 4
 501         self.assertRaises(csv.Error, mydialect)
 502
 503     def test_delimiter(self):
 504         class mydialect(csv.Dialect):
 505             delimiter = ";"
 506             escapechar = '\\'
 507             doublequote = False
 508             skipinitialspace = True
 509             lineterminator = '\r\n'
 510             quoting = csv.QUOTE_NONE
 511         d = mydialect()
 512
 513         mydialect.delimiter = ":::"
 514         self.assertRaises(csv.Error, mydialect)
 515
 516         mydialect.delimiter = 4
 517         self.assertRaises(csv.Error, mydialect)
 518
 519     def test_lineterminator(self):
 520         class mydialect(csv.Dialect):
 521             delimiter = ";"
 522             escapechar = '\\'
 523             doublequote = False
 524             skipinitialspace = True
 525             lineterminator = '\r\n'
 526             quoting = csv.QUOTE_NONE
 527         d = mydialect()
 528
 529         mydialect.lineterminator = ":::"
 530         d = mydialect()
 531
 532         mydialect.lineterminator = 4
 533         self.assertRaises(csv.Error, mydialect)
 534
 535
 536 class TestSniffer(unittest.TestCase):
 537     sample1 = """\
 538 Harry's, Arlington Heights, IL, 2/1/03, Kimi Hayes
 539 Shark City, Glendale Heights, IL, 12/28/02, Prezence
 540 Tommy's Place, Blue Island, IL, 12/28/02, Blue Sunday/White Crow
 541 Stonecutters Seafood and Chop House, Lemont, IL, 12/19/02, Week Back
 542 """
 543     sample2 = """\
 544 'Harry''s':'Arlington Heights':'IL':'2/1/03':'Kimi Hayes'
 545 'Shark City':'Glendale Heights':'IL':'12/28/02':'Prezence'
 546 'Tommy''s Place':'Blue Island':'IL':'12/28/02':'Blue Sunday/White Crow'
 547 'Stonecutters Seafood and Chop House':'Lemont':'IL':'12/19/02':'Week Back'
 548 """
 549
 550     header = '''\
 551 "venue","city","state","date","performers"
 552 '''
 553     def test_has_header(self):
 554         sniffer = csv.Sniffer()
 555         self.assertEqual(sniffer.has_header(self.sample1), False)
 556         self.assertEqual(sniffer.has_header(self.header+self.sample1), True)
 557
 558     def test_sniff(self):
 559         sniffer = csv.Sniffer()
 560         dialect = sniffer.sniff(self.sample1)
 561         self.assertEqual(dialect.delimiter, ",")
 562         self.assertEqual(dialect.quotechar, '"')
 563         self.assertEqual(dialect.skipinitialspace, True)
 564
 565         dialect = sniffer.sniff(self.sample2)
 566         self.assertEqual(dialect.delimiter, ":")
 567         self.assertEqual(dialect.quotechar, "'")
 568         self.assertEqual(dialect.skipinitialspace, False)
 569
 570 if not hasattr(sys, "gettotalrefcount"):
 571     if verbose: print "*** skipping leakage tests ***"
 572 else:
 573     class NUL:
 574         def write(s, *args):
 575             pass
 576         writelines = write
 577
 578     class TestLeaks(unittest.TestCase):
 579         def test_create_read(self):
 580             delta = 0
 581             lastrc = sys.gettotalrefcount()
 582             for i in xrange(20):
 583                 gc.collect()
 584                 self.assertEqual(gc.garbage, [])
 585                 rc = sys.gettotalrefcount()
 586                 csv.reader(["a,b,c\r\n"])
 587                 csv.reader(["a,b,c\r\n"])
 588                 csv.reader(["a,b,c\r\n"])
 589                 delta = rc-lastrc
 590                 lastrc = rc
 591             # if csv.reader() leaks, last delta should be 3 or more
 592             self.assertEqual(delta < 3, True)
 593
 594         def test_create_write(self):
 595             delta = 0
 596             lastrc = sys.gettotalrefcount()
 597             s = NUL()
 598             for i in xrange(20):
 599                 gc.collect()
 600                 self.assertEqual(gc.garbage, [])
 601                 rc = sys.gettotalrefcount()
 602                 csv.writer(s)
 603                 csv.writer(s)
 604                 csv.writer(s)
 605                 delta = rc-lastrc
 606                 lastrc = rc
 607             # if csv.writer() leaks, last delta should be 3 or more
 608             self.assertEqual(delta < 3, True)
 609
 610         def test_read(self):
 611             delta = 0
 612             rows = ["a,b,c\r\n"]*5
 613             lastrc = sys.gettotalrefcount()
 614             for i in xrange(20):
 615                 gc.collect()
 616                 self.assertEqual(gc.garbage, [])
 617                 rc = sys.gettotalrefcount()
 618                 rdr = csv.reader(rows)
 619                 for row in rdr:
 620                     pass
 621                 delta = rc-lastrc
 622                 lastrc = rc
 623             # if reader leaks during read, delta should be 5 or more
 624             self.assertEqual(delta < 5, True)
 625
 626         def test_write(self):
 627             delta = 0
 628             rows = [[1,2,3]]*5
 629             s = NUL()
 630             lastrc = sys.gettotalrefcount()
 631             for i in xrange(20):
 632                 gc.collect()
 633                 self.assertEqual(gc.garbage, [])
 634                 rc = sys.gettotalrefcount()
 635                 writer = csv.writer(s)
 636                 for row in rows:
 637                     writer.writerow(row)
 638                 delta = rc-lastrc
 639                 lastrc = rc
 640             # if writer leaks during write, last delta should be 5 or more
 641             self.assertEqual(delta < 5, True)
 642
 643 def _testclasses():
 644     mod = sys.modules[__name__]
 645     return [getattr(mod, name) for name in dir(mod) if name.startswith('Test')]
 646
 647 def suite():
 648     suite = unittest.TestSuite()
 649     for testclass in _testclasses():
 650         suite.addTest(unittest.makeSuite(testclass))
 651     return suite
 652
 653 if __name__ == '__main__':
 654     unittest.main(defaultTest='suite')