1 files changed, 102 insertions, 0 deletions
diff --git a/tests/test_regexopt.py b/tests/test_regexopt.py
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+++ b/tests/test_regexopt.py
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+"""
+    Tests for pygments.regexopt
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+    :copyright: Copyright 2006-2022 by the Pygments team, see AUTHORS.
+    :license: BSD, see LICENSE for details.
+"""
+
+import re
+import random
+from itertools import combinations_with_replacement
+
+from pygments.regexopt import regex_opt
+
+ALPHABET = ['a', 'b', 'c', 'd', 'e']
+
+N_TRIES = 15
+
+
+def generate_keywordlist(length):
+    return [''.join(p) for p in
+            combinations_with_replacement(ALPHABET, length)]
+
+
+def test_randomly():
+    # generate a list of all possible keywords of a certain length using
+    # a restricted alphabet, then choose some to match and make sure only
+    # those do
+    for n in range(3, N_TRIES):
+        kwlist = generate_keywordlist(n)
+        to_match = random.sample(kwlist,
+                                 random.randint(1, len(kwlist) - 1))
+        no_match = set(kwlist) - set(to_match)
+        rex = re.compile(regex_opt(to_match))
+        assert rex.groups == 1
+        for w in to_match:
+            assert rex.match(w)
+        for w in no_match:
+            assert not rex.match(w)
+
+
+def test_prefix():
+    opt = regex_opt(('a', 'b'), prefix=r':{1,2}')
+    print(opt)
+    rex = re.compile(opt)
+    assert not rex.match('a')
+    assert rex.match('::a')
+    assert not rex.match(':::')  # fullmatch
+
+
+def test_suffix():
+    opt = regex_opt(('a', 'b'), suffix=r':{1,2}')
+    print(opt)
+    rex = re.compile(opt)
+    assert not rex.match('a')
+    assert rex.match('a::')
+    assert not rex.match(':::')  # fullmatch
+
+
+def test_suffix_opt():
+    # test that detected suffixes remain sorted.
+    opt = regex_opt(('afoo', 'abfoo'))
+    print(opt)
+    rex = re.compile(opt)
+    m = rex.match('abfoo')
+    assert m.end() == 5
+
+
+def test_different_length_grouping():
+    opt = regex_opt(('a', 'xyz'))
+    print(opt)
+    rex = re.compile(opt)
+    assert rex.match('a')
+    assert rex.match('xyz')
+    assert not rex.match('b')
+    assert rex.groups == 1
+
+
+def test_same_length_grouping():
+    opt = regex_opt(('a', 'b'))
+    print(opt)
+    rex = re.compile(opt)
+    assert rex.match('a')
+    assert rex.match('b')
+    assert not rex.match('x')
+
+    assert rex.groups == 1
+    groups = rex.match('a').groups()
+    assert groups == ('a',)
+
+
+def test_same_length_suffix_grouping():
+    opt = regex_opt(('a', 'b'), suffix='(m)')
+    print(opt)
+    rex = re.compile(opt)
+    assert rex.match('am')
+    assert rex.match('bm')
+    assert not rex.match('xm')
+    assert not rex.match('ax')
+    assert rex.groups == 2
+    groups = rex.match('am').groups()
+    assert groups == ('a', 'm')