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1 //! Support code for rustc's built in unit-test and micro-benchmarking
2 //! framework.
3 //!
4 //! Almost all user code will only be interested in `Bencher` and
5 //! `black_box`. All other interactions (such as writing tests and
6 //! benchmarks themselves) should be done via the `#[test]` and
7 //! `#[bench]` attributes.
8 //!
9 //! See the [Testing Chapter](../book/ch11-00-testing.html) of the book for more
10 //! details.
11
12 // Currently, not much of this is meant for users. It is intended to
13 // support the simplest interface possible for representing and
14 // running tests while providing a base that other test frameworks may
15 // build off of.
16
17 #![unstable(feature = "test", issue = "50297")]
18 #![doc(test(attr(deny(warnings))))]
19 #![feature(internal_output_capture)]
20 #![feature(is_terminal)]
21 #![feature(staged_api)]
22 #![feature(process_exitcode_internals)]
23 #![feature(test)]
24
25 // Public reexports
26 pub use self::bench::{black_box, Bencher};
27 pub use self::console::run_tests_console;
28 pub use self::options::{ColorConfig, Options, OutputFormat, RunIgnored, ShouldPanic};
29 pub use self::types::TestName::*;
30 pub use self::types::*;
31 pub use self::ColorConfig::*;
32 pub use cli::TestOpts;
33
34 // Module to be used by rustc to compile tests in libtest
35 pub mod test {
36     pub use crate::{
37         assert_test_result,
38         bench::Bencher,
39         cli::{parse_opts, TestOpts},
40         filter_tests,
41         helpers::metrics::{Metric, MetricMap},
42         options::{Concurrent, Options, RunIgnored, RunStrategy, ShouldPanic},
43         run_test, test_main, test_main_static,
44         test_result::{TestResult, TrFailed, TrFailedMsg, TrIgnored, TrOk},
45         time::{TestExecTime, TestTimeOptions},
46         types::{
47             DynTestFn, DynTestName, StaticBenchFn, StaticTestFn, StaticTestName, TestDesc,
48             TestDescAndFn, TestId, TestName, TestType,
49         },
50     };
51 }
52
53 use std::{
54     collections::VecDeque,
55     env, io,
56     io::prelude::Write,
57     panic::{self, catch_unwind, AssertUnwindSafe, PanicInfo},
58     process::{self, Command, Termination},
59     sync::mpsc::{channel, Sender},
60     sync::{Arc, Mutex},
61     thread,
62     time::{Duration, Instant},
63 };
64
65 pub mod bench;
66 mod cli;
67 mod console;
68 mod event;
69 mod formatters;
70 mod helpers;
71 mod options;
72 pub mod stats;
73 mod term;
74 mod test_result;
75 mod time;
76 mod types;
77
78 #[cfg(test)]
79 mod tests;
80
81 use core::any::Any;
82 use event::{CompletedTest, TestEvent};
83 use helpers::concurrency::get_concurrency;
84 use helpers::exit_code::get_exit_code;
85 use helpers::shuffle::{get_shuffle_seed, shuffle_tests};
86 use options::{Concurrent, RunStrategy};
87 use test_result::*;
88 use time::TestExecTime;
89
90 // Process exit code to be used to indicate test failures.
91 const ERROR_EXIT_CODE: i32 = 101;
92
93 const SECONDARY_TEST_INVOKER_VAR: &str = "__RUST_TEST_INVOKE";
94
95 // The default console test runner. It accepts the command line
96 // arguments and a vector of test_descs.
97 pub fn test_main(args: &[String], tests: Vec<TestDescAndFn>, options: Option<Options>) {
98     let mut opts = match cli::parse_opts(args) {
99         Some(Ok(o)) => o,
100         Some(Err(msg)) => {
101             eprintln!("error: {msg}");
102             process::exit(ERROR_EXIT_CODE);
103         }
104         None => return,
105     };
106     if let Some(options) = options {
107         opts.options = options;
108     }
109     if opts.list {
110         if let Err(e) = console::list_tests_console(&opts, tests) {
111             eprintln!("error: io error when listing tests: {e:?}");
112             process::exit(ERROR_EXIT_CODE);
113         }
114     } else {
115         match console::run_tests_console(&opts, tests) {
116             Ok(true) => {}
117             Ok(false) => process::exit(ERROR_EXIT_CODE),
118             Err(e) => {
119                 eprintln!("error: io error when listing tests: {e:?}");
120                 process::exit(ERROR_EXIT_CODE);
121             }
122         }
123     }
124 }
125
126 /// A variant optimized for invocation with a static test vector.
127 /// This will panic (intentionally) when fed any dynamic tests.
128 ///
129 /// This is the entry point for the main function generated by `rustc --test`
130 /// when panic=unwind.
131 pub fn test_main_static(tests: &[&TestDescAndFn]) {
132     let args = env::args().collect::<Vec<_>>();
133     let owned_tests: Vec<_> = tests.iter().map(make_owned_test).collect();
134     test_main(&args, owned_tests, None)
135 }
136
137 /// A variant optimized for invocation with a static test vector.
138 /// This will panic (intentionally) when fed any dynamic tests.
139 ///
140 /// Runs tests in panic=abort mode, which involves spawning subprocesses for
141 /// tests.
142 ///
143 /// This is the entry point for the main function generated by `rustc --test`
144 /// when panic=abort.
145 pub fn test_main_static_abort(tests: &[&TestDescAndFn]) {
146     // If we're being run in SpawnedSecondary mode, run the test here. run_test
147     // will then exit the process.
148     if let Ok(name) = env::var(SECONDARY_TEST_INVOKER_VAR) {
149         env::remove_var(SECONDARY_TEST_INVOKER_VAR);
150         let test = tests
151             .iter()
152             .filter(|test| test.desc.name.as_slice() == name)
153             .map(make_owned_test)
154             .next()
155             .unwrap_or_else(|| panic!("couldn't find a test with the provided name '{name}'"));
156         let TestDescAndFn { desc, testfn } = test;
157         let testfn = match testfn {
158             StaticTestFn(f) => f,
159             _ => panic!("only static tests are supported"),
160         };
161         run_test_in_spawned_subprocess(desc, Box::new(testfn));
162     }
163
164     let args = env::args().collect::<Vec<_>>();
165     let owned_tests: Vec<_> = tests.iter().map(make_owned_test).collect();
166     test_main(&args, owned_tests, Some(Options::new().panic_abort(true)))
167 }
168
169 /// Clones static values for putting into a dynamic vector, which test_main()
170 /// needs to hand out ownership of tests to parallel test runners.
171 ///
172 /// This will panic when fed any dynamic tests, because they cannot be cloned.
173 fn make_owned_test(test: &&TestDescAndFn) -> TestDescAndFn {
174     match test.testfn {
175         StaticTestFn(f) => TestDescAndFn { testfn: StaticTestFn(f), desc: test.desc.clone() },
176         StaticBenchFn(f) => TestDescAndFn { testfn: StaticBenchFn(f), desc: test.desc.clone() },
177         _ => panic!("non-static tests passed to test::test_main_static"),
178     }
179 }
180
181 /// Invoked when unit tests terminate. Returns `Result::Err` if the test is
182 /// considered a failure. By default, invokes `report() and checks for a `0`
183 /// result.
184 pub fn assert_test_result<T: Termination>(result: T) -> Result<(), String> {
185     let code = result.report().to_i32();
186     if code == 0 {
187         Ok(())
188     } else {
189         Err(format!(
190             "the test returned a termination value with a non-zero status code \
191              ({}) which indicates a failure",
192             code
193         ))
194     }
195 }
196
197 pub fn run_tests<F>(
198     opts: &TestOpts,
199     tests: Vec<TestDescAndFn>,
200     mut notify_about_test_event: F,
201 ) -> io::Result<()>
202 where
203     F: FnMut(TestEvent) -> io::Result<()>,
204 {
205     use std::collections::{self, HashMap};
206     use std::hash::BuildHasherDefault;
207     use std::sync::mpsc::RecvTimeoutError;
208
209     struct RunningTest {
210         join_handle: Option<thread::JoinHandle<()>>,
211     }
212
213     // Use a deterministic hasher
214     type TestMap =
215         HashMap<TestId, RunningTest, BuildHasherDefault<collections::hash_map::DefaultHasher>>;
216
217     struct TimeoutEntry {
218         id: TestId,
219         desc: TestDesc,
220         timeout: Instant,
221     }
222
223     let tests_len = tests.len();
224
225     let mut filtered_tests = filter_tests(opts, tests);
226     if !opts.bench_benchmarks {
227         filtered_tests = convert_benchmarks_to_tests(filtered_tests);
228     }
229
230     let filtered_tests = {
231         let mut filtered_tests = filtered_tests;
232         for test in filtered_tests.iter_mut() {
233             test.desc.name = test.desc.name.with_padding(test.testfn.padding());
234         }
235
236         filtered_tests
237     };
238
239     let filtered_out = tests_len - filtered_tests.len();
240     let event = TestEvent::TeFilteredOut(filtered_out);
241     notify_about_test_event(event)?;
242
243     let filtered_descs = filtered_tests.iter().map(|t| t.desc.clone()).collect();
244
245     let shuffle_seed = get_shuffle_seed(opts);
246
247     let event = TestEvent::TeFiltered(filtered_descs, shuffle_seed);
248     notify_about_test_event(event)?;
249
250     let (mut filtered_tests, filtered_benchs): (Vec<_>, _) = filtered_tests
251         .into_iter()
252         .enumerate()
253         .map(|(i, e)| (TestId(i), e))
254         .partition(|(_, e)| matches!(e.testfn, StaticTestFn(_) | DynTestFn(_)));
255
256     let concurrency = opts.test_threads.unwrap_or_else(get_concurrency);
257
258     if let Some(shuffle_seed) = shuffle_seed {
259         shuffle_tests(shuffle_seed, &mut filtered_tests);
260     }
261     // Store the tests in a VecDeque so we can efficiently remove the first element to run the
262     // tests in the order they were passed (unless shuffled).
263     let mut remaining = VecDeque::from(filtered_tests);
264     let mut pending = 0;
265
266     let (tx, rx) = channel::<CompletedTest>();
267     let run_strategy = if opts.options.panic_abort && !opts.force_run_in_process {
268         RunStrategy::SpawnPrimary
269     } else {
270         RunStrategy::InProcess
271     };
272
273     let mut running_tests: TestMap = HashMap::default();
274     let mut timeout_queue: VecDeque<TimeoutEntry> = VecDeque::new();
275
276     fn get_timed_out_tests(
277         running_tests: &TestMap,
278         timeout_queue: &mut VecDeque<TimeoutEntry>,
279     ) -> Vec<TestDesc> {
280         let now = Instant::now();
281         let mut timed_out = Vec::new();
282         while let Some(timeout_entry) = timeout_queue.front() {
283             if now < timeout_entry.timeout {
284                 break;
285             }
286             let timeout_entry = timeout_queue.pop_front().unwrap();
287             if running_tests.contains_key(&timeout_entry.id) {
288                 timed_out.push(timeout_entry.desc);
289             }
290         }
291         timed_out
292     }
293
294     fn calc_timeout(timeout_queue: &VecDeque<TimeoutEntry>) -> Option<Duration> {
295         timeout_queue.front().map(|&TimeoutEntry { timeout: next_timeout, .. }| {
296             let now = Instant::now();
297             if next_timeout >= now { next_timeout - now } else { Duration::new(0, 0) }
298         })
299     }
300
301     if concurrency == 1 {
302         while !remaining.is_empty() {
303             let (id, test) = remaining.pop_front().unwrap();
304             let event = TestEvent::TeWait(test.desc.clone());
305             notify_about_test_event(event)?;
306             let join_handle =
307                 run_test(opts, !opts.run_tests, id, test, run_strategy, tx.clone(), Concurrent::No);
308             assert!(join_handle.is_none());
309             let completed_test = rx.recv().unwrap();
310
311             let event = TestEvent::TeResult(completed_test);
312             notify_about_test_event(event)?;
313         }
314     } else {
315         while pending > 0 || !remaining.is_empty() {
316             while pending < concurrency && !remaining.is_empty() {
317                 let (id, test) = remaining.pop_front().unwrap();
318                 let timeout = time::get_default_test_timeout();
319                 let desc = test.desc.clone();
320
321                 let event = TestEvent::TeWait(desc.clone());
322                 notify_about_test_event(event)?; //here no pad
323                 let join_handle = run_test(
324                     opts,
325                     !opts.run_tests,
326                     id,
327                     test,
328                     run_strategy,
329                     tx.clone(),
330                     Concurrent::Yes,
331                 );
332                 running_tests.insert(id, RunningTest { join_handle });
333                 timeout_queue.push_back(TimeoutEntry { id, desc, timeout });
334                 pending += 1;
335             }
336
337             let mut res;
338             loop {
339                 if let Some(timeout) = calc_timeout(&timeout_queue) {
340                     res = rx.recv_timeout(timeout);
341                     for test in get_timed_out_tests(&running_tests, &mut timeout_queue) {
342                         let event = TestEvent::TeTimeout(test);
343                         notify_about_test_event(event)?;
344                     }
345
346                     match res {
347                         Err(RecvTimeoutError::Timeout) => {
348                             // Result is not yet ready, continue waiting.
349                         }
350                         _ => {
351                             // We've got a result, stop the loop.
352                             break;
353                         }
354                     }
355                 } else {
356                     res = rx.recv().map_err(|_| RecvTimeoutError::Disconnected);
357                     break;
358                 }
359             }
360
361             let mut completed_test = res.unwrap();
362             let running_test = running_tests.remove(&completed_test.id).unwrap();
363             if let Some(join_handle) = running_test.join_handle {
364                 if let Err(_) = join_handle.join() {
365                     if let TrOk = completed_test.result {
366                         completed_test.result =
367                             TrFailedMsg("panicked after reporting success".to_string());
368                     }
369                 }
370             }
371
372             let event = TestEvent::TeResult(completed_test);
373             notify_about_test_event(event)?;
374             pending -= 1;
375         }
376     }
377
378     if opts.bench_benchmarks {
379         // All benchmarks run at the end, in serial.
380         for (id, b) in filtered_benchs {
381             let event = TestEvent::TeWait(b.desc.clone());
382             notify_about_test_event(event)?;
383             run_test(opts, false, id, b, run_strategy, tx.clone(), Concurrent::No);
384             let completed_test = rx.recv().unwrap();
385
386             let event = TestEvent::TeResult(completed_test);
387             notify_about_test_event(event)?;
388         }
389     }
390     Ok(())
391 }
392
393 pub fn filter_tests(opts: &TestOpts, tests: Vec<TestDescAndFn>) -> Vec<TestDescAndFn> {
394     let mut filtered = tests;
395     let matches_filter = |test: &TestDescAndFn, filter: &str| {
396         let test_name = test.desc.name.as_slice();
397
398         match opts.filter_exact {
399             true => test_name == filter,
400             false => test_name.contains(filter),
401         }
402     };
403
404     // Remove tests that don't match the test filter
405     if !opts.filters.is_empty() {
406         filtered.retain(|test| opts.filters.iter().any(|filter| matches_filter(test, filter)));
407     }
408
409     // Skip tests that match any of the skip filters
410     filtered.retain(|test| !opts.skip.iter().any(|sf| matches_filter(test, sf)));
411
412     // Excludes #[should_panic] tests
413     if opts.exclude_should_panic {
414         filtered.retain(|test| test.desc.should_panic == ShouldPanic::No);
415     }
416
417     // maybe unignore tests
418     match opts.run_ignored {
419         RunIgnored::Yes => {
420             filtered.iter_mut().for_each(|test| test.desc.ignore = false);
421         }
422         RunIgnored::Only => {
423             filtered.retain(|test| test.desc.ignore);
424             filtered.iter_mut().for_each(|test| test.desc.ignore = false);
425         }
426         RunIgnored::No => {}
427     }
428
429     filtered
430 }
431
432 pub fn convert_benchmarks_to_tests(tests: Vec<TestDescAndFn>) -> Vec<TestDescAndFn> {
433     // convert benchmarks to tests, if we're not benchmarking them
434     tests
435         .into_iter()
436         .map(|x| {
437             let testfn = match x.testfn {
438                 DynBenchFn(benchfn) => DynTestFn(Box::new(move || {
439                     bench::run_once(|b| __rust_begin_short_backtrace(|| benchfn(b)))
440                 })),
441                 StaticBenchFn(benchfn) => DynTestFn(Box::new(move || {
442                     bench::run_once(|b| __rust_begin_short_backtrace(|| benchfn(b)))
443                 })),
444                 f => f,
445             };
446             TestDescAndFn { desc: x.desc, testfn }
447         })
448         .collect()
449 }
450
451 pub fn run_test(
452     opts: &TestOpts,
453     force_ignore: bool,
454     id: TestId,
455     test: TestDescAndFn,
456     strategy: RunStrategy,
457     monitor_ch: Sender<CompletedTest>,
458     concurrency: Concurrent,
459 ) -> Option<thread::JoinHandle<()>> {
460     let TestDescAndFn { desc, testfn } = test;
461
462     // Emscripten can catch panics but other wasm targets cannot
463     let ignore_because_no_process_support = desc.should_panic != ShouldPanic::No
464         && cfg!(target_family = "wasm")
465         && !cfg!(target_os = "emscripten");
466
467     if force_ignore || desc.ignore || ignore_because_no_process_support {
468         let message = CompletedTest::new(id, desc, TrIgnored, None, Vec::new());
469         monitor_ch.send(message).unwrap();
470         return None;
471     }
472
473     struct TestRunOpts {
474         pub strategy: RunStrategy,
475         pub nocapture: bool,
476         pub concurrency: Concurrent,
477         pub time: Option<time::TestTimeOptions>,
478     }
479
480     fn run_test_inner(
481         id: TestId,
482         desc: TestDesc,
483         monitor_ch: Sender<CompletedTest>,
484         testfn: Box<dyn FnOnce() -> Result<(), String> + Send>,
485         opts: TestRunOpts,
486     ) -> Option<thread::JoinHandle<()>> {
487         let concurrency = opts.concurrency;
488         let name = desc.name.clone();
489
490         let runtest = move || match opts.strategy {
491             RunStrategy::InProcess => run_test_in_process(
492                 id,
493                 desc,
494                 opts.nocapture,
495                 opts.time.is_some(),
496                 testfn,
497                 monitor_ch,
498                 opts.time,
499             ),
500             RunStrategy::SpawnPrimary => spawn_test_subprocess(
501                 id,
502                 desc,
503                 opts.nocapture,
504                 opts.time.is_some(),
505                 monitor_ch,
506                 opts.time,
507             ),
508         };
509
510         // If the platform is single-threaded we're just going to run
511         // the test synchronously, regardless of the concurrency
512         // level.
513         let supports_threads = !cfg!(target_os = "emscripten") && !cfg!(target_family = "wasm");
514         if concurrency == Concurrent::Yes && supports_threads {
515             let cfg = thread::Builder::new().name(name.as_slice().to_owned());
516             let mut runtest = Arc::new(Mutex::new(Some(runtest)));
517             let runtest2 = runtest.clone();
518             match cfg.spawn(move || runtest2.lock().unwrap().take().unwrap()()) {
519                 Ok(handle) => Some(handle),
520                 Err(e) if e.kind() == io::ErrorKind::WouldBlock => {
521                     // `ErrorKind::WouldBlock` means hitting the thread limit on some
522                     // platforms, so run the test synchronously here instead.
523                     Arc::get_mut(&mut runtest).unwrap().get_mut().unwrap().take().unwrap()();
524                     None
525                 }
526                 Err(e) => panic!("failed to spawn thread to run test: {e}"),
527             }
528         } else {
529             runtest();
530             None
531         }
532     }
533
534     let test_run_opts =
535         TestRunOpts { strategy, nocapture: opts.nocapture, concurrency, time: opts.time_options };
536
537     match testfn {
538         DynBenchFn(benchfn) => {
539             // Benchmarks aren't expected to panic, so we run them all in-process.
540             crate::bench::benchmark(id, desc, monitor_ch, opts.nocapture, benchfn);
541             None
542         }
543         StaticBenchFn(benchfn) => {
544             // Benchmarks aren't expected to panic, so we run them all in-process.
545             crate::bench::benchmark(id, desc, monitor_ch, opts.nocapture, benchfn);
546             None
547         }
548         DynTestFn(f) => {
549             match strategy {
550                 RunStrategy::InProcess => (),
551                 _ => panic!("Cannot run dynamic test fn out-of-process"),
552             };
553             run_test_inner(
554                 id,
555                 desc,
556                 monitor_ch,
557                 Box::new(move || __rust_begin_short_backtrace(f)),
558                 test_run_opts,
559             )
560         }
561         StaticTestFn(f) => run_test_inner(
562             id,
563             desc,
564             monitor_ch,
565             Box::new(move || __rust_begin_short_backtrace(f)),
566             test_run_opts,
567         ),
568     }
569 }
570
571 /// Fixed frame used to clean the backtrace with `RUST_BACKTRACE=1`.
572 #[inline(never)]
573 fn __rust_begin_short_backtrace<T, F: FnOnce() -> T>(f: F) -> T {
574     let result = f();
575
576     // prevent this frame from being tail-call optimised away
577     black_box(result)
578 }
579
580 fn run_test_in_process(
581     id: TestId,
582     desc: TestDesc,
583     nocapture: bool,
584     report_time: bool,
585     testfn: Box<dyn FnOnce() -> Result<(), String> + Send>,
586     monitor_ch: Sender<CompletedTest>,
587     time_opts: Option<time::TestTimeOptions>,
588 ) {
589     // Buffer for capturing standard I/O
590     let data = Arc::new(Mutex::new(Vec::new()));
591
592     if !nocapture {
593         io::set_output_capture(Some(data.clone()));
594     }
595
596     let start = report_time.then(Instant::now);
597     let result = fold_err(catch_unwind(AssertUnwindSafe(testfn)));
598     let exec_time = start.map(|start| {
599         let duration = start.elapsed();
600         TestExecTime(duration)
601     });
602
603     io::set_output_capture(None);
604
605     let test_result = match result {
606         Ok(()) => calc_result(&desc, Ok(()), &time_opts, &exec_time),
607         Err(e) => calc_result(&desc, Err(e.as_ref()), &time_opts, &exec_time),
608     };
609     let stdout = data.lock().unwrap_or_else(|e| e.into_inner()).to_vec();
610     let message = CompletedTest::new(id, desc, test_result, exec_time, stdout);
611     monitor_ch.send(message).unwrap();
612 }
613
614 fn fold_err<T, E>(
615     result: Result<Result<T, E>, Box<dyn Any + Send>>,
616 ) -> Result<T, Box<dyn Any + Send>>
617 where
618     E: Send + 'static,
619 {
620     match result {
621         Ok(Err(e)) => Err(Box::new(e)),
622         Ok(Ok(v)) => Ok(v),
623         Err(e) => Err(e),
624     }
625 }
626
627 fn spawn_test_subprocess(
628     id: TestId,
629     desc: TestDesc,
630     nocapture: bool,
631     report_time: bool,
632     monitor_ch: Sender<CompletedTest>,
633     time_opts: Option<time::TestTimeOptions>,
634 ) {
635     let (result, test_output, exec_time) = (|| {
636         let args = env::args().collect::<Vec<_>>();
637         let current_exe = &args[0];
638
639         let mut command = Command::new(current_exe);
640         command.env(SECONDARY_TEST_INVOKER_VAR, desc.name.as_slice());
641         if nocapture {
642             command.stdout(process::Stdio::inherit());
643             command.stderr(process::Stdio::inherit());
644         }
645
646         let start = report_time.then(Instant::now);
647         let output = match command.output() {
648             Ok(out) => out,
649             Err(e) => {
650                 let err = format!("Failed to spawn {} as child for test: {:?}", args[0], e);
651                 return (TrFailed, err.into_bytes(), None);
652             }
653         };
654         let exec_time = start.map(|start| {
655             let duration = start.elapsed();
656             TestExecTime(duration)
657         });
658
659         let std::process::Output { stdout, stderr, status } = output;
660         let mut test_output = stdout;
661         formatters::write_stderr_delimiter(&mut test_output, &desc.name);
662         test_output.extend_from_slice(&stderr);
663
664         let result = match (|| -> Result<TestResult, String> {
665             let exit_code = get_exit_code(status)?;
666             Ok(get_result_from_exit_code(&desc, exit_code, &time_opts, &exec_time))
667         })() {
668             Ok(r) => r,
669             Err(e) => {
670                 write!(&mut test_output, "Unexpected error: {}", e).unwrap();
671                 TrFailed
672             }
673         };
674
675         (result, test_output, exec_time)
676     })();
677
678     let message = CompletedTest::new(id, desc, result, exec_time, test_output);
679     monitor_ch.send(message).unwrap();
680 }
681
682 fn run_test_in_spawned_subprocess(
683     desc: TestDesc,
684     testfn: Box<dyn FnOnce() -> Result<(), String> + Send>,
685 ) -> ! {
686     let builtin_panic_hook = panic::take_hook();
687     let record_result = Arc::new(move |panic_info: Option<&'_ PanicInfo<'_>>| {
688         let test_result = match panic_info {
689             Some(info) => calc_result(&desc, Err(info.payload()), &None, &None),
690             None => calc_result(&desc, Ok(()), &None, &None),
691         };
692
693         // We don't support serializing TrFailedMsg, so just
694         // print the message out to stderr.
695         if let TrFailedMsg(msg) = &test_result {
696             eprintln!("{msg}");
697         }
698
699         if let Some(info) = panic_info {
700             builtin_panic_hook(info);
701         }
702
703         if let TrOk = test_result {
704             process::exit(test_result::TR_OK);
705         } else {
706             process::exit(test_result::TR_FAILED);
707         }
708     });
709     let record_result2 = record_result.clone();
710     panic::set_hook(Box::new(move |info| record_result2(Some(&info))));
711     if let Err(message) = testfn() {
712         panic!("{}", message);
713     }
714     record_result(None);
715     unreachable!("panic=abort callback should have exited the process")
716 }