1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
|
// Copyright 2008 The RE2 Authors. All Rights Reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Exhaustive testing of regular expression matching.
// Each test picks an alphabet (e.g., "abc"), a maximum string length,
// a maximum regular expression length, and a maximum number of letters
// that can appear in the regular expression. Given these parameters,
// it tries every possible regular expression and string, verifying that
// the NFA, DFA, and a trivial backtracking implementation agree about
// the location of the match.
#include <stdio.h>
#include "absl/base/macros.h"
#include "absl/flags/flag.h"
#include "absl/strings/str_format.h"
#include "gtest/gtest.h"
#include "util/logging.h"
#include "re2/testing/exhaustive_tester.h"
#include "re2/testing/tester.h"
// For target `log' in the Makefile.
#ifndef LOGGING
#define LOGGING 0
#endif
ABSL_FLAG(bool, show_regexps, false, "show regexps during testing");
ABSL_FLAG(int, max_bad_regexp_inputs, 1,
"Stop testing a regular expression after finding this many "
"strings that break it.");
namespace re2 {
static char* escape(absl::string_view sp) {
static char buf[512];
char* p = buf;
*p++ = '\"';
for (size_t i = 0; i < sp.size(); i++) {
if(p+5 >= buf+sizeof buf)
LOG(FATAL) << "ExhaustiveTester escape: too long";
if(sp[i] == '\\' || sp[i] == '\"') {
*p++ = '\\';
*p++ = sp[i];
} else if(sp[i] == '\n') {
*p++ = '\\';
*p++ = 'n';
} else {
*p++ = sp[i];
}
}
*p++ = '\"';
*p = '\0';
return buf;
}
static void PrintResult(const RE2& re, absl::string_view input,
RE2::Anchor anchor, absl::string_view* m, int n) {
if (!re.Match(input, 0, input.size(), anchor, m, n)) {
absl::PrintF("-");
return;
}
for (int i = 0; i < n; i++) {
if (i > 0)
absl::PrintF(" ");
if (m[i].data() == NULL)
absl::PrintF("-");
else
absl::PrintF("%d-%d",
BeginPtr(m[i]) - BeginPtr(input),
EndPtr(m[i]) - BeginPtr(input));
}
}
// Processes a single generated regexp.
// Compiles it using Regexp interface and PCRE, and then
// checks that NFA, DFA, and PCRE all return the same results.
void ExhaustiveTester::HandleRegexp(const std::string& const_regexp) {
regexps_++;
std::string regexp = const_regexp;
if (!topwrapper_.empty()) {
auto fmt = absl::ParsedFormat<'s'>::New(topwrapper_);
CHECK(fmt != nullptr);
regexp = absl::StrFormat(*fmt, regexp);
}
if (absl::GetFlag(FLAGS_show_regexps)) {
absl::PrintF("\r%s", regexp);
fflush(stdout);
}
if (LOGGING) {
// Write out test cases and answers for use in testing
// other implementations, such as Go's regexp package.
if (randomstrings_)
LOG(ERROR) << "Cannot log with random strings.";
if (regexps_ == 1) { // first
absl::PrintF("strings\n");
strgen_.Reset();
while (strgen_.HasNext())
absl::PrintF("%s\n", escape(strgen_.Next()));
absl::PrintF("regexps\n");
}
absl::PrintF("%s\n", escape(regexp));
RE2 re(regexp);
RE2::Options longest;
longest.set_longest_match(true);
RE2 relongest(regexp, longest);
int ngroup = re.NumberOfCapturingGroups()+1;
absl::string_view* group = new absl::string_view[ngroup];
strgen_.Reset();
while (strgen_.HasNext()) {
absl::string_view input = strgen_.Next();
PrintResult(re, input, RE2::ANCHOR_BOTH, group, ngroup);
absl::PrintF(";");
PrintResult(re, input, RE2::UNANCHORED, group, ngroup);
absl::PrintF(";");
PrintResult(relongest, input, RE2::ANCHOR_BOTH, group, ngroup);
absl::PrintF(";");
PrintResult(relongest, input, RE2::UNANCHORED, group, ngroup);
absl::PrintF("\n");
}
delete[] group;
return;
}
Tester tester(regexp);
if (tester.error())
return;
strgen_.Reset();
strgen_.GenerateNULL();
if (randomstrings_)
strgen_.Random(stringseed_, stringcount_);
int bad_inputs = 0;
while (strgen_.HasNext()) {
tests_++;
if (!tester.TestInput(strgen_.Next())) {
failures_++;
if (++bad_inputs >= absl::GetFlag(FLAGS_max_bad_regexp_inputs))
break;
}
}
}
// Runs an exhaustive test on the given parameters.
void ExhaustiveTest(int maxatoms, int maxops,
const std::vector<std::string>& alphabet,
const std::vector<std::string>& ops,
int maxstrlen,
const std::vector<std::string>& stralphabet,
const std::string& wrapper,
const std::string& topwrapper) {
if (RE2_DEBUG_MODE) {
if (maxatoms > 1)
maxatoms--;
if (maxops > 1)
maxops--;
if (maxstrlen > 1)
maxstrlen--;
}
ExhaustiveTester t(maxatoms, maxops, alphabet, ops,
maxstrlen, stralphabet, wrapper,
topwrapper);
t.Generate();
if (!LOGGING) {
absl::PrintF("%d regexps, %d tests, %d failures [%d/%d str]\n",
t.regexps(), t.tests(), t.failures(), maxstrlen, stralphabet.size());
}
EXPECT_EQ(0, t.failures());
}
// Runs an exhaustive test using the given parameters and
// the basic egrep operators.
void EgrepTest(int maxatoms, int maxops, const std::string& alphabet,
int maxstrlen, const std::string& stralphabet,
const std::string& wrapper) {
const char* tops[] = { "", "^(?:%s)", "(?:%s)$", "^(?:%s)$" };
for (size_t i = 0; i < ABSL_ARRAYSIZE(tops); i++) {
ExhaustiveTest(maxatoms, maxops,
Split("", alphabet),
RegexpGenerator::EgrepOps(),
maxstrlen,
Split("", stralphabet),
wrapper,
tops[i]);
}
}
} // namespace re2
|
