proxygen
gtest-death-test.h
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29 //
30 // Author: wan@google.com (Zhanyong Wan)
31 //
32 // The Google C++ Testing Framework (Google Test)
33 //
34 // This header file defines the public API for death tests. It is
35 // #included by gtest.h so a user doesn't need to include this
36 // directly.
37 
38 #ifndef GTEST_INCLUDE_GTEST_GTEST_DEATH_TEST_H_
39 #define GTEST_INCLUDE_GTEST_GTEST_DEATH_TEST_H_
40 
41 #include "gtest/internal/gtest-death-test-internal.h"
42 
43 namespace testing {
44 
45 // This flag controls the style of death tests. Valid values are "threadsafe",
46 // meaning that the death test child process will re-execute the test binary
47 // from the start, running only a single death test, or "fast",
48 // meaning that the child process will execute the test logic immediately
49 // after forking.
50 GTEST_DECLARE_string_(death_test_style);
51 
52 #if GTEST_HAS_DEATH_TEST
53 
54 namespace internal {
55 
56 // Returns a Boolean value indicating whether the caller is currently
57 // executing in the context of the death test child process. Tools such as
58 // Valgrind heap checkers may need this to modify their behavior in death
59 // tests. IMPORTANT: This is an internal utility. Using it may break the
60 // implementation of death tests. User code MUST NOT use it.
61 GTEST_API_ bool InDeathTestChild();
62 
63 } // namespace internal
64 
65 // The following macros are useful for writing death tests.
66 
67 // Here's what happens when an ASSERT_DEATH* or EXPECT_DEATH* is
68 // executed:
69 //
70 // 1. It generates a warning if there is more than one active
71 // thread. This is because it's safe to fork() or clone() only
72 // when there is a single thread.
73 //
74 // 2. The parent process clone()s a sub-process and runs the death
75 // test in it; the sub-process exits with code 0 at the end of the
76 // death test, if it hasn't exited already.
77 //
78 // 3. The parent process waits for the sub-process to terminate.
79 //
80 // 4. The parent process checks the exit code and error message of
81 // the sub-process.
82 //
83 // Examples:
84 //
85 // ASSERT_DEATH(server.SendMessage(56, "Hello"), "Invalid port number");
86 // for (int i = 0; i < 5; i++) {
87 // EXPECT_DEATH(server.ProcessRequest(i),
88 // "Invalid request .* in ProcessRequest()")
89 // << "Failed to die on request " << i;
90 // }
91 //
92 // ASSERT_EXIT(server.ExitNow(), ::testing::ExitedWithCode(0), "Exiting");
93 //
94 // bool KilledBySIGHUP(int exit_code) {
95 // return WIFSIGNALED(exit_code) && WTERMSIG(exit_code) == SIGHUP;
96 // }
97 //
98 // ASSERT_EXIT(client.HangUpServer(), KilledBySIGHUP, "Hanging up!");
99 //
100 // On the regular expressions used in death tests:
101 //
102 // On POSIX-compliant systems (*nix), we use the <regex.h> library,
103 // which uses the POSIX extended regex syntax.
104 //
105 // On other platforms (e.g. Windows), we only support a simple regex
106 // syntax implemented as part of Google Test. This limited
107 // implementation should be enough most of the time when writing
108 // death tests; though it lacks many features you can find in PCRE
109 // or POSIX extended regex syntax. For example, we don't support
110 // union ("x|y"), grouping ("(xy)"), brackets ("[xy]"), and
111 // repetition count ("x{5,7}"), among others.
112 //
113 // Below is the syntax that we do support. We chose it to be a
114 // subset of both PCRE and POSIX extended regex, so it's easy to
115 // learn wherever you come from. In the following: 'A' denotes a
116 // literal character, period (.), or a single \\ escape sequence;
117 // 'x' and 'y' denote regular expressions; 'm' and 'n' are for
118 // natural numbers.
119 //
120 // c matches any literal character c
121 // \\d matches any decimal digit
122 // \\D matches any character that's not a decimal digit
123 // \\f matches \f
124 // \\n matches \n
125 // \\r matches \r
126 // \\s matches any ASCII whitespace, including \n
127 // \\S matches any character that's not a whitespace
128 // \\t matches \t
129 // \\v matches \v
130 // \\w matches any letter, _, or decimal digit
131 // \\W matches any character that \\w doesn't match
132 // \\c matches any literal character c, which must be a punctuation
133 // . matches any single character except \n
134 // A? matches 0 or 1 occurrences of A
135 // A* matches 0 or many occurrences of A
136 // A+ matches 1 or many occurrences of A
137 // ^ matches the beginning of a string (not that of each line)
138 // $ matches the end of a string (not that of each line)
139 // xy matches x followed by y
140 //
141 // If you accidentally use PCRE or POSIX extended regex features
142 // not implemented by us, you will get a run-time failure. In that
143 // case, please try to rewrite your regular expression within the
144 // above syntax.
145 //
146 // This implementation is *not* meant to be as highly tuned or robust
147 // as a compiled regex library, but should perform well enough for a
148 // death test, which already incurs significant overhead by launching
149 // a child process.
150 //
151 // Known caveats:
152 //
153 // A "threadsafe" style death test obtains the path to the test
154 // program from argv[0] and re-executes it in the sub-process. For
155 // simplicity, the current implementation doesn't search the PATH
156 // when launching the sub-process. This means that the user must
157 // invoke the test program via a path that contains at least one
158 // path separator (e.g. path/to/foo_test and
159 // /absolute/path/to/bar_test are fine, but foo_test is not). This
160 // is rarely a problem as people usually don't put the test binary
161 // directory in PATH.
162 //
163 // TODO(wan@google.com): make thread-safe death tests search the PATH.
164 
165 // Asserts that a given statement causes the program to exit, with an
166 // integer exit status that satisfies predicate, and emitting error output
167 // that matches regex.
168 # define ASSERT_EXIT(statement, predicate, regex) \
169  GTEST_DEATH_TEST_(statement, predicate, regex, GTEST_FATAL_FAILURE_)
170 
171 // Like ASSERT_EXIT, but continues on to successive tests in the
172 // test case, if any:
173 # define EXPECT_EXIT(statement, predicate, regex) \
174  GTEST_DEATH_TEST_(statement, predicate, regex, GTEST_NONFATAL_FAILURE_)
175 
176 // Asserts that a given statement causes the program to exit, either by
177 // explicitly exiting with a nonzero exit code or being killed by a
178 // signal, and emitting error output that matches regex.
179 # define ASSERT_DEATH(statement, regex) \
180  ASSERT_EXIT(statement, ::testing::internal::ExitedUnsuccessfully, regex)
181 
182 // Like ASSERT_DEATH, but continues on to successive tests in the
183 // test case, if any:
184 # define EXPECT_DEATH(statement, regex) \
185  EXPECT_EXIT(statement, ::testing::internal::ExitedUnsuccessfully, regex)
186 
187 // Two predicate classes that can be used in {ASSERT,EXPECT}_EXIT*:
188 
189 // Tests that an exit code describes a normal exit with a given exit code.
190 class GTEST_API_ ExitedWithCode {
191  public:
192  explicit ExitedWithCode(int exit_code);
193  bool operator()(int exit_status) const;
194  private:
195  // No implementation - assignment is unsupported.
196  void operator=(const ExitedWithCode& other);
197 
198  const int exit_code_;
199 };
200 
201 # if !GTEST_OS_WINDOWS
202 // Tests that an exit code describes an exit due to termination by a
203 // given signal.
204 class GTEST_API_ KilledBySignal {
205  public:
206  explicit KilledBySignal(int signum);
207  bool operator()(int exit_status) const;
208  private:
209  const int signum_;
210 };
211 # endif // !GTEST_OS_WINDOWS
212 
213 // EXPECT_DEBUG_DEATH asserts that the given statements die in debug mode.
214 // The death testing framework causes this to have interesting semantics,
215 // since the sideeffects of the call are only visible in opt mode, and not
216 // in debug mode.
217 //
218 // In practice, this can be used to test functions that utilize the
219 // LOG(DFATAL) macro using the following style:
220 //
221 // int DieInDebugOr12(int* sideeffect) {
222 // if (sideeffect) {
223 // *sideeffect = 12;
224 // }
225 // LOG(DFATAL) << "death";
226 // return 12;
227 // }
228 //
229 // TEST(TestCase, TestDieOr12WorksInDgbAndOpt) {
230 // int sideeffect = 0;
231 // // Only asserts in dbg.
232 // EXPECT_DEBUG_DEATH(DieInDebugOr12(&sideeffect), "death");
233 //
234 // #ifdef NDEBUG
235 // // opt-mode has sideeffect visible.
236 // EXPECT_EQ(12, sideeffect);
237 // #else
238 // // dbg-mode no visible sideeffect.
239 // EXPECT_EQ(0, sideeffect);
240 // #endif
241 // }
242 //
243 // This will assert that DieInDebugReturn12InOpt() crashes in debug
244 // mode, usually due to a DCHECK or LOG(DFATAL), but returns the
245 // appropriate fallback value (12 in this case) in opt mode. If you
246 // need to test that a function has appropriate side-effects in opt
247 // mode, include assertions against the side-effects. A general
248 // pattern for this is:
249 //
250 // EXPECT_DEBUG_DEATH({
251 // // Side-effects here will have an effect after this statement in
252 // // opt mode, but none in debug mode.
253 // EXPECT_EQ(12, DieInDebugOr12(&sideeffect));
254 // }, "death");
255 //
256 # ifdef NDEBUG
257 
258 # define EXPECT_DEBUG_DEATH(statement, regex) \
259  GTEST_EXECUTE_STATEMENT_(statement, regex)
260 
261 # define ASSERT_DEBUG_DEATH(statement, regex) \
262  GTEST_EXECUTE_STATEMENT_(statement, regex)
263 
264 # else
265 
266 # define EXPECT_DEBUG_DEATH(statement, regex) \
267  EXPECT_DEATH(statement, regex)
268 
269 # define ASSERT_DEBUG_DEATH(statement, regex) \
270  ASSERT_DEATH(statement, regex)
271 
272 # endif // NDEBUG for EXPECT_DEBUG_DEATH
273 #endif // GTEST_HAS_DEATH_TEST
274 
275 // EXPECT_DEATH_IF_SUPPORTED(statement, regex) and
276 // ASSERT_DEATH_IF_SUPPORTED(statement, regex) expand to real death tests if
277 // death tests are supported; otherwise they just issue a warning. This is
278 // useful when you are combining death test assertions with normal test
279 // assertions in one test.
280 #if GTEST_HAS_DEATH_TEST
281 # define EXPECT_DEATH_IF_SUPPORTED(statement, regex) \
282  EXPECT_DEATH(statement, regex)
283 # define ASSERT_DEATH_IF_SUPPORTED(statement, regex) \
284  ASSERT_DEATH(statement, regex)
285 #else
286 # define EXPECT_DEATH_IF_SUPPORTED(statement, regex) \
287  GTEST_UNSUPPORTED_DEATH_TEST_(statement, regex, )
288 # define ASSERT_DEATH_IF_SUPPORTED(statement, regex) \
289  GTEST_UNSUPPORTED_DEATH_TEST_(statement, regex, return)
290 #endif
291 
292 } // namespace testing
293 
294 #endif // GTEST_INCLUDE_GTEST_GTEST_DEATH_TEST_H_
#define GTEST_API_
Definition: gtest-port.h:934
GTEST_DECLARE_string_(death_test_style)