Lib/test/test_difflib.py

   1 import difflib
   2 from test.test_support import run_unittest, findfile
   3 import unittest
   4 import doctest
   5 import sys
   6
   7 class TestSFbugs(unittest.TestCase):
   8
   9     def test_ratio_for_null_seqn(self):
  10         # Check clearing of SF bug 763023
  11         s = difflib.SequenceMatcher(None, [], [])
  12         self.assertEqual(s.ratio(), 1)
  13         self.assertEqual(s.quick_ratio(), 1)
  14         self.assertEqual(s.real_quick_ratio(), 1)
  15
  16     def test_comparing_empty_lists(self):
  17         # Check fix for bug #979794
  18         group_gen = difflib.SequenceMatcher(None, [], []).get_grouped_opcodes()
  19         self.assertRaises(StopIteration, group_gen.next)
  20         diff_gen = difflib.unified_diff([], [])
  21         self.assertRaises(StopIteration, diff_gen.next)
  22
  23     def test_added_tab_hint(self):
  24         # Check fix for bug #1488943
  25         diff = list(difflib.Differ().compare(["\tI am a buggy"],["\t\tI am a bug"]))
  26         self.assertEqual("- \tI am a buggy", diff[0])
  27         self.assertEqual("?            --\n", diff[1])
  28         self.assertEqual("+ \t\tI am a bug", diff[2])
  29         self.assertEqual("? +\n", diff[3])
  30
  31 patch914575_from1 = """
  32    1. Beautiful is beTTer than ugly.
  33    2. Explicit is better than implicit.
  34    3. Simple is better than complex.
  35    4. Complex is better than complicated.
  36 """
  37
  38 patch914575_to1 = """
  39    1. Beautiful is better than ugly.
  40    3.   Simple is better than complex.
  41    4. Complicated is better than complex.
  42    5. Flat is better than nested.
  43 """
  44
  45 patch914575_from2 = """
  46 \t\tLine 1: preceeded by from:[tt] to:[ssss]
  47   \t\tLine 2: preceeded by from:[sstt] to:[sssst]
  48   \t \tLine 3: preceeded by from:[sstst] to:[ssssss]
  49 Line 4:  \thas from:[sst] to:[sss] after :
  50 Line 5: has from:[t] to:[ss] at end\t
  51 """
  52
  53 patch914575_to2 = """
  54     Line 1: preceeded by from:[tt] to:[ssss]
  55     \tLine 2: preceeded by from:[sstt] to:[sssst]
  56       Line 3: preceeded by from:[sstst] to:[ssssss]
  57 Line 4:   has from:[sst] to:[sss] after :
  58 Line 5: has from:[t] to:[ss] at end
  59 """
  60
  61 patch914575_from3 = """line 0
  62 1234567890123456789012345689012345
  63 line 1
  64 line 2
  65 line 3
  66 line 4   changed
  67 line 5   changed
  68 line 6   changed
  69 line 7
  70 line 8  subtracted
  71 line 9
  72 1234567890123456789012345689012345
  73 short line
  74 just fits in!!
  75 just fits in two lines yup!!
  76 the end"""
  77
  78 patch914575_to3 = """line 0
  79 1234567890123456789012345689012345
  80 line 1
  81 line 2    added
  82 line 3
  83 line 4   chanGEd
  84 line 5a  chanGed
  85 line 6a  changEd
  86 line 7
  87 line 8
  88 line 9
  89 1234567890
  90 another long line that needs to be wrapped
  91 just fitS in!!
  92 just fits in two lineS yup!!
  93 the end"""
  94
  95 class TestSFpatches(unittest.TestCase):
  96
  97     def test_html_diff(self):
  98         # Check SF patch 914575 for generating HTML differences
  99         f1a = ((patch914575_from1 + '123\n'*10)*3)
 100         t1a = (patch914575_to1 + '123\n'*10)*3
 101         f1b = '456\n'*10 + f1a
 102         t1b = '456\n'*10 + t1a
 103         f1a = f1a.splitlines()
 104         t1a = t1a.splitlines()
 105         f1b = f1b.splitlines()
 106         t1b = t1b.splitlines()
 107         f2 = patch914575_from2.splitlines()
 108         t2 = patch914575_to2.splitlines()
 109         f3 = patch914575_from3
 110         t3 = patch914575_to3
 111         i = difflib.HtmlDiff()
 112         j = difflib.HtmlDiff(tabsize=2)
 113         k = difflib.HtmlDiff(wrapcolumn=14)
 114
 115         full = i.make_file(f1a,t1a,'from','to',context=False,numlines=5)
 116         tables = '\n'.join(
 117             [
 118              '<h2>Context (first diff within numlines=5(default))</h2>',
 119              i.make_table(f1a,t1a,'from','to',context=True),
 120              '<h2>Context (first diff after numlines=5(default))</h2>',
 121              i.make_table(f1b,t1b,'from','to',context=True),
 122              '<h2>Context (numlines=6)</h2>',
 123              i.make_table(f1a,t1a,'from','to',context=True,numlines=6),
 124              '<h2>Context (numlines=0)</h2>',
 125              i.make_table(f1a,t1a,'from','to',context=True,numlines=0),
 126              '<h2>Same Context</h2>',
 127              i.make_table(f1a,f1a,'from','to',context=True),
 128              '<h2>Same Full</h2>',
 129              i.make_table(f1a,f1a,'from','to',context=False),
 130              '<h2>Empty Context</h2>',
 131              i.make_table([],[],'from','to',context=True),
 132              '<h2>Empty Full</h2>',
 133              i.make_table([],[],'from','to',context=False),
 134              '<h2>tabsize=2</h2>',
 135              j.make_table(f2,t2),
 136              '<h2>tabsize=default</h2>',
 137              i.make_table(f2,t2),
 138              '<h2>Context (wrapcolumn=14,numlines=0)</h2>',
 139              k.make_table(f3.splitlines(),t3.splitlines(),context=True,numlines=0),
 140              '<h2>wrapcolumn=14,splitlines()</h2>',
 141              k.make_table(f3.splitlines(),t3.splitlines()),
 142              '<h2>wrapcolumn=14,splitlines(True)</h2>',
 143              k.make_table(f3.splitlines(True),t3.splitlines(True)),
 144              ])
 145         actual = full.replace('</body>','\n%s\n</body>' % tables)
 146
 147         # temporarily uncomment next two lines to baseline this test
 148         #with open('test_difflib_expect.html','w') as fp:
 149         #    fp.write(actual)
 150
 151         with open(findfile('test_difflib_expect.html')) as fp:
 152             self.assertEqual(actual, fp.read())
 153
 154     def test_recursion_limit(self):
 155         # Check if the problem described in patch #1413711 exists.
 156         limit = sys.getrecursionlimit()
 157         old = [(i%2 and "K:%d" or "V:A:%d") % i for i in range(limit*2)]
 158         new = [(i%2 and "K:%d" or "V:B:%d") % i for i in range(limit*2)]
 159         difflib.SequenceMatcher(None, old, new).get_opcodes()
 160
 161
 162 class TestOutputFormat(unittest.TestCase):
 163     def test_tab_delimiter(self):
 164         args = ['one', 'two', 'Original', 'Current',
 165             '2005-01-26 23:30:50', '2010-04-02 10:20:52']
 166         ud = difflib.unified_diff(*args, lineterm='')
 167         self.assertEqual(list(ud)[0:2], [
 168                            "--- Original\t2005-01-26 23:30:50",
 169                            "+++ Current\t2010-04-02 10:20:52"])
 170         cd = difflib.context_diff(*args, lineterm='')
 171         self.assertEqual(list(cd)[0:2], [
 172                            "*** Original\t2005-01-26 23:30:50",
 173                            "--- Current\t2010-04-02 10:20:52"])
 174
 175     def test_no_trailing_tab_on_empty_filedate(self):
 176         args = ['one', 'two', 'Original', 'Current']
 177         ud = difflib.unified_diff(*args, lineterm='')
 178         self.assertEqual(list(ud)[0:2], ["--- Original", "+++ Current"])
 179
 180         cd = difflib.context_diff(*args, lineterm='')
 181         self.assertEqual(list(cd)[0:2], ["*** Original", "--- Current"])
 182
 183
 184 def test_main():
 185     difflib.HtmlDiff._default_prefix = 0
 186     Doctests = doctest.DocTestSuite(difflib)
 187     run_unittest(TestSFpatches, TestSFbugs, TestOutputFormat, Doctests)
 188
 189 if __name__ == '__main__':
 190     test_main()