library/test/src/lib.rs

   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 details.
  10
  11 // Currently, not much of this is meant for users. It is intended to
  12 // support the simplest interface possible for representing and
  13 // running tests while providing a base that other test frameworks may
  14 // build off of.
  15
  16 #![unstable(feature = "test", issue = "50297")]
  17 #![doc(test(attr(deny(warnings))))]
  18 #![feature(nll)]
  19 #![feature(bench_black_box)]
  20 #![feature(internal_output_capture)]
  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 event::{CompletedTest, TestEvent};
  82 use helpers::concurrency::get_concurrency;
  83 use helpers::exit_code::get_exit_code;
  84 use helpers::shuffle::{get_shuffle_seed, shuffle_tests};
  85 use options::{Concurrent, RunStrategy};
  86 use test_result::*;
  87 use time::TestExecTime;
  88
  89 // Process exit code to be used to indicate test failures.
  90 const ERROR_EXIT_CODE: i32 = 101;
  91
  92 const SECONDARY_TEST_INVOKER_VAR: &str = "__RUST_TEST_INVOKE";
  93
  94 // The default console test runner. It accepts the command line
  95 // arguments and a vector of test_descs.
  96 pub fn test_main(args: &[String], tests: Vec<TestDescAndFn>, options: Option<Options>) {
  97     let mut opts = match cli::parse_opts(args) {
  98         Some(Ok(o)) => o,
  99         Some(Err(msg)) => {
 100             eprintln!("error: {msg}");
 101             process::exit(ERROR_EXIT_CODE);
 102         }
 103         None => return,
 104     };
 105     if let Some(options) = options {
 106         opts.options = options;
 107     }
 108     if opts.list {
 109         if let Err(e) = console::list_tests_console(&opts, tests) {
 110             eprintln!("error: io error when listing tests: {e:?}");
 111             process::exit(ERROR_EXIT_CODE);
 112         }
 113     } else {
 114         match console::run_tests_console(&opts, tests) {
 115             Ok(true) => {}
 116             Ok(false) => process::exit(ERROR_EXIT_CODE),
 117             Err(e) => {
 118                 eprintln!("error: io error when listing tests: {e:?}");
 119                 process::exit(ERROR_EXIT_CODE);
 120             }
 121         }
 122     }
 123 }
 124
 125 /// A variant optimized for invocation with a static test vector.
 126 /// This will panic (intentionally) when fed any dynamic tests.
 127 ///
 128 /// This is the entry point for the main function generated by `rustc --test`
 129 /// when panic=unwind.
 130 pub fn test_main_static(tests: &[&TestDescAndFn]) {
 131     let args = env::args().collect::<Vec<_>>();
 132     let owned_tests: Vec<_> = tests.iter().map(make_owned_test).collect();
 133     test_main(&args, owned_tests, None)
 134 }
 135
 136 /// A variant optimized for invocation with a static test vector.
 137 /// This will panic (intentionally) when fed any dynamic tests.
 138 ///
 139 /// Runs tests in panic=abort mode, which involves spawning subprocesses for
 140 /// tests.
 141 ///
 142 /// This is the entry point for the main function generated by `rustc --test`
 143 /// when panic=abort.
 144 pub fn test_main_static_abort(tests: &[&TestDescAndFn]) {
 145     // If we're being run in SpawnedSecondary mode, run the test here. run_test
 146     // will then exit the process.
 147     if let Ok(name) = env::var(SECONDARY_TEST_INVOKER_VAR) {
 148         env::remove_var(SECONDARY_TEST_INVOKER_VAR);
 149         let test = tests
 150             .iter()
 151             .filter(|test| test.desc.name.as_slice() == name)
 152             .map(make_owned_test)
 153             .next()
 154             .unwrap_or_else(|| panic!("couldn't find a test with the provided name '{name}'"));
 155         let TestDescAndFn { desc, testfn } = test;
 156         let testfn = match testfn {
 157             StaticTestFn(f) => f,
 158             _ => panic!("only static tests are supported"),
 159         };
 160         run_test_in_spawned_subprocess(desc, Box::new(testfn));
 161     }
 162
 163     let args = env::args().collect::<Vec<_>>();
 164     let owned_tests: Vec<_> = tests.iter().map(make_owned_test).collect();
 165     test_main(&args, owned_tests, Some(Options::new().panic_abort(true)))
 166 }
 167
 168 /// Clones static values for putting into a dynamic vector, which test_main()
 169 /// needs to hand out ownership of tests to parallel test runners.
 170 ///
 171 /// This will panic when fed any dynamic tests, because they cannot be cloned.
 172 fn make_owned_test(test: &&TestDescAndFn) -> TestDescAndFn {
 173     match test.testfn {
 174         StaticTestFn(f) => TestDescAndFn { testfn: StaticTestFn(f), desc: test.desc.clone() },
 175         StaticBenchFn(f) => TestDescAndFn { testfn: StaticBenchFn(f), desc: test.desc.clone() },
 176         _ => panic!("non-static tests passed to test::test_main_static"),
 177     }
 178 }
 179
 180 /// Invoked when unit tests terminate. Should panic if the unit
 181 /// Tests is considered a failure. By default, invokes `report()`
 182 /// and checks for a `0` result.
 183 pub fn assert_test_result<T: Termination>(result: T) {
 184     let code = result.report().to_i32();
 185     assert_eq!(
 186         code, 0,
 187         "the test returned a termination value with a non-zero status code ({}) \
 188          which indicates a failure",
 189         code
 190     );
 191 }
 192
 193 pub fn run_tests<F>(
 194     opts: &TestOpts,
 195     tests: Vec<TestDescAndFn>,
 196     mut notify_about_test_event: F,
 197 ) -> io::Result<()>
 198 where
 199     F: FnMut(TestEvent) -> io::Result<()>,
 200 {
 201     use std::collections::{self, HashMap};
 202     use std::hash::BuildHasherDefault;
 203     use std::sync::mpsc::RecvTimeoutError;
 204
 205     struct RunningTest {
 206         join_handle: Option<thread::JoinHandle<()>>,
 207     }
 208
 209     // Use a deterministic hasher
 210     type TestMap =
 211         HashMap<TestId, RunningTest, BuildHasherDefault<collections::hash_map::DefaultHasher>>;
 212
 213     struct TimeoutEntry {
 214         id: TestId,
 215         desc: TestDesc,
 216         timeout: Instant,
 217     }
 218
 219     let tests_len = tests.len();
 220
 221     let mut filtered_tests = filter_tests(opts, tests);
 222     if !opts.bench_benchmarks {
 223         filtered_tests = convert_benchmarks_to_tests(filtered_tests);
 224     }
 225
 226     let filtered_tests = {
 227         let mut filtered_tests = filtered_tests;
 228         for test in filtered_tests.iter_mut() {
 229             test.desc.name = test.desc.name.with_padding(test.testfn.padding());
 230         }
 231
 232         filtered_tests
 233     };
 234
 235     let filtered_out = tests_len - filtered_tests.len();
 236     let event = TestEvent::TeFilteredOut(filtered_out);
 237     notify_about_test_event(event)?;
 238
 239     let filtered_descs = filtered_tests.iter().map(|t| t.desc.clone()).collect();
 240
 241     let shuffle_seed = get_shuffle_seed(opts);
 242
 243     let event = TestEvent::TeFiltered(filtered_descs, shuffle_seed);
 244     notify_about_test_event(event)?;
 245
 246     let (filtered_tests, filtered_benchs): (Vec<_>, _) = filtered_tests
 247         .into_iter()
 248         .enumerate()
 249         .map(|(i, e)| (TestId(i), e))
 250         .partition(|(_, e)| matches!(e.testfn, StaticTestFn(_) | DynTestFn(_)));
 251
 252     let concurrency = opts.test_threads.unwrap_or_else(get_concurrency);
 253
 254     let mut remaining = filtered_tests;
 255     if let Some(shuffle_seed) = shuffle_seed {
 256         shuffle_tests(shuffle_seed, &mut remaining);
 257     } else {
 258         remaining.reverse();
 259     }
 260     let mut pending = 0;
 261
 262     let (tx, rx) = channel::<CompletedTest>();
 263     let run_strategy = if opts.options.panic_abort && !opts.force_run_in_process {
 264         RunStrategy::SpawnPrimary
 265     } else {
 266         RunStrategy::InProcess
 267     };
 268
 269     let mut running_tests: TestMap = HashMap::default();
 270     let mut timeout_queue: VecDeque<TimeoutEntry> = VecDeque::new();
 271
 272     fn get_timed_out_tests(
 273         running_tests: &TestMap,
 274         timeout_queue: &mut VecDeque<TimeoutEntry>,
 275     ) -> Vec<TestDesc> {
 276         let now = Instant::now();
 277         let mut timed_out = Vec::new();
 278         while let Some(timeout_entry) = timeout_queue.front() {
 279             if now < timeout_entry.timeout {
 280                 break;
 281             }
 282             let timeout_entry = timeout_queue.pop_front().unwrap();
 283             if running_tests.contains_key(&timeout_entry.id) {
 284                 timed_out.push(timeout_entry.desc);
 285             }
 286         }
 287         timed_out
 288     }
 289
 290     fn calc_timeout(timeout_queue: &VecDeque<TimeoutEntry>) -> Option<Duration> {
 291         timeout_queue.front().map(|&TimeoutEntry { timeout: next_timeout, .. }| {
 292             let now = Instant::now();
 293             if next_timeout >= now { next_timeout - now } else { Duration::new(0, 0) }
 294         })
 295     }
 296
 297     if concurrency == 1 {
 298         while !remaining.is_empty() {
 299             let (id, test) = remaining.pop().unwrap();
 300             let event = TestEvent::TeWait(test.desc.clone());
 301             notify_about_test_event(event)?;
 302             let join_handle =
 303                 run_test(opts, !opts.run_tests, id, test, run_strategy, tx.clone(), Concurrent::No);
 304             assert!(join_handle.is_none());
 305             let completed_test = rx.recv().unwrap();
 306
 307             let event = TestEvent::TeResult(completed_test);
 308             notify_about_test_event(event)?;
 309         }
 310     } else {
 311         while pending > 0 || !remaining.is_empty() {
 312             while pending < concurrency && !remaining.is_empty() {
 313                 let (id, test) = remaining.pop().unwrap();
 314                 let timeout = time::get_default_test_timeout();
 315                 let desc = test.desc.clone();
 316
 317                 let event = TestEvent::TeWait(desc.clone());
 318                 notify_about_test_event(event)?; //here no pad
 319                 let join_handle = run_test(
 320                     opts,
 321                     !opts.run_tests,
 322                     id,
 323                     test,
 324                     run_strategy,
 325                     tx.clone(),
 326                     Concurrent::Yes,
 327                 );
 328                 running_tests.insert(id, RunningTest { join_handle });
 329                 timeout_queue.push_back(TimeoutEntry { id, desc, timeout });
 330                 pending += 1;
 331             }
 332
 333             let mut res;
 334             loop {
 335                 if let Some(timeout) = calc_timeout(&timeout_queue) {
 336                     res = rx.recv_timeout(timeout);
 337                     for test in get_timed_out_tests(&running_tests, &mut timeout_queue) {
 338                         let event = TestEvent::TeTimeout(test);
 339                         notify_about_test_event(event)?;
 340                     }
 341
 342                     match res {
 343                         Err(RecvTimeoutError::Timeout) => {
 344                             // Result is not yet ready, continue waiting.
 345                         }
 346                         _ => {
 347                             // We've got a result, stop the loop.
 348                             break;
 349                         }
 350                     }
 351                 } else {
 352                     res = rx.recv().map_err(|_| RecvTimeoutError::Disconnected);
 353                     break;
 354                 }
 355             }
 356
 357             let mut completed_test = res.unwrap();
 358             let running_test = running_tests.remove(&completed_test.id).unwrap();
 359             if let Some(join_handle) = running_test.join_handle {
 360                 if let Err(_) = join_handle.join() {
 361                     if let TrOk = completed_test.result {
 362                         completed_test.result =
 363                             TrFailedMsg("panicked after reporting success".to_string());
 364                     }
 365                 }
 366             }
 367
 368             let event = TestEvent::TeResult(completed_test);
 369             notify_about_test_event(event)?;
 370             pending -= 1;
 371         }
 372     }
 373
 374     if opts.bench_benchmarks {
 375         // All benchmarks run at the end, in serial.
 376         for (id, b) in filtered_benchs {
 377             let event = TestEvent::TeWait(b.desc.clone());
 378             notify_about_test_event(event)?;
 379             run_test(opts, false, id, b, run_strategy, tx.clone(), Concurrent::No);
 380             let completed_test = rx.recv().unwrap();
 381
 382             let event = TestEvent::TeResult(completed_test);
 383             notify_about_test_event(event)?;
 384         }
 385     }
 386     Ok(())
 387 }
 388
 389 pub fn filter_tests(opts: &TestOpts, tests: Vec<TestDescAndFn>) -> Vec<TestDescAndFn> {
 390     let mut filtered = tests;
 391     let matches_filter = |test: &TestDescAndFn, filter: &str| {
 392         let test_name = test.desc.name.as_slice();
 393
 394         match opts.filter_exact {
 395             true => test_name == filter,
 396             false => test_name.contains(filter),
 397         }
 398     };
 399
 400     // Remove tests that don't match the test filter
 401     if !opts.filters.is_empty() {
 402         filtered.retain(|test| opts.filters.iter().any(|filter| matches_filter(test, filter)));
 403     }
 404
 405     // Skip tests that match any of the skip filters
 406     filtered.retain(|test| !opts.skip.iter().any(|sf| matches_filter(test, sf)));
 407
 408     // Excludes #[should_panic] tests
 409     if opts.exclude_should_panic {
 410         filtered.retain(|test| test.desc.should_panic == ShouldPanic::No);
 411     }
 412
 413     // maybe unignore tests
 414     match opts.run_ignored {
 415         RunIgnored::Yes => {
 416             filtered.iter_mut().for_each(|test| test.desc.ignore = false);
 417         }
 418         RunIgnored::Only => {
 419             filtered.retain(|test| test.desc.ignore);
 420             filtered.iter_mut().for_each(|test| test.desc.ignore = false);
 421         }
 422         RunIgnored::No => {}
 423     }
 424
 425     // Sort the tests alphabetically
 426     filtered.sort_by(|t1, t2| t1.desc.name.as_slice().cmp(t2.desc.name.as_slice()));
 427
 428     filtered
 429 }
 430
 431 pub fn convert_benchmarks_to_tests(tests: Vec<TestDescAndFn>) -> Vec<TestDescAndFn> {
 432     // convert benchmarks to tests, if we're not benchmarking them
 433     tests
 434         .into_iter()
 435         .map(|x| {
 436             let testfn = match x.testfn {
 437                 DynBenchFn(benchfn) => DynTestFn(Box::new(move || {
 438                     bench::run_once(|b| __rust_begin_short_backtrace(|| benchfn(b)))
 439                 })),
 440                 StaticBenchFn(benchfn) => DynTestFn(Box::new(move || {
 441                     bench::run_once(|b| __rust_begin_short_backtrace(|| benchfn(b)))
 442                 })),
 443                 f => f,
 444             };
 445             TestDescAndFn { desc: x.desc, testfn }
 446         })
 447         .collect()
 448 }
 449
 450 pub fn run_test(
 451     opts: &TestOpts,
 452     force_ignore: bool,
 453     id: TestId,
 454     test: TestDescAndFn,
 455     strategy: RunStrategy,
 456     monitor_ch: Sender<CompletedTest>,
 457     concurrency: Concurrent,
 458 ) -> Option<thread::JoinHandle<()>> {
 459     let TestDescAndFn { desc, testfn } = test;
 460
 461     // Emscripten can catch panics but other wasm targets cannot
 462     let ignore_because_no_process_support = desc.should_panic != ShouldPanic::No
 463         && cfg!(target_family = "wasm")
 464         && !cfg!(target_os = "emscripten");
 465
 466     if force_ignore || desc.ignore || ignore_because_no_process_support {
 467         let message = CompletedTest::new(id, desc, TrIgnored, None, Vec::new());
 468         monitor_ch.send(message).unwrap();
 469         return None;
 470     }
 471
 472     struct TestRunOpts {
 473         pub strategy: RunStrategy,
 474         pub nocapture: bool,
 475         pub concurrency: Concurrent,
 476         pub time: Option<time::TestTimeOptions>,
 477     }
 478
 479     fn run_test_inner(
 480         id: TestId,
 481         desc: TestDesc,
 482         monitor_ch: Sender<CompletedTest>,
 483         testfn: Box<dyn FnOnce() + Send>,
 484         opts: TestRunOpts,
 485     ) -> Option<thread::JoinHandle<()>> {
 486         let concurrency = opts.concurrency;
 487         let name = desc.name.clone();
 488
 489         let runtest = move || match opts.strategy {
 490             RunStrategy::InProcess => run_test_in_process(
 491                 id,
 492                 desc,
 493                 opts.nocapture,
 494                 opts.time.is_some(),
 495                 testfn,
 496                 monitor_ch,
 497                 opts.time,
 498             ),
 499             RunStrategy::SpawnPrimary => spawn_test_subprocess(
 500                 id,
 501                 desc,
 502                 opts.nocapture,
 503                 opts.time.is_some(),
 504                 monitor_ch,
 505                 opts.time,
 506             ),
 507         };
 508
 509         // If the platform is single-threaded we're just going to run
 510         // the test synchronously, regardless of the concurrency
 511         // level.
 512         let supports_threads = !cfg!(target_os = "emscripten") && !cfg!(target_family = "wasm");
 513         if concurrency == Concurrent::Yes && supports_threads {
 514             let cfg = thread::Builder::new().name(name.as_slice().to_owned());
 515             let mut runtest = Arc::new(Mutex::new(Some(runtest)));
 516             let runtest2 = runtest.clone();
 517             match cfg.spawn(move || runtest2.lock().unwrap().take().unwrap()()) {
 518                 Ok(handle) => Some(handle),
 519                 Err(e) if e.kind() == io::ErrorKind::WouldBlock => {
 520                     // `ErrorKind::WouldBlock` means hitting the thread limit on some
 521                     // platforms, so run the test synchronously here instead.
 522                     Arc::get_mut(&mut runtest).unwrap().get_mut().unwrap().take().unwrap()();
 523                     None
 524                 }
 525                 Err(e) => panic!("failed to spawn thread to run test: {e}"),
 526             }
 527         } else {
 528             runtest();
 529             None
 530         }
 531     }
 532
 533     let test_run_opts =
 534         TestRunOpts { strategy, nocapture: opts.nocapture, concurrency, time: opts.time_options };
 535
 536     match testfn {
 537         DynBenchFn(benchfn) => {
 538             // Benchmarks aren't expected to panic, so we run them all in-process.
 539             crate::bench::benchmark(id, desc, monitor_ch, opts.nocapture, benchfn);
 540             None
 541         }
 542         StaticBenchFn(benchfn) => {
 543             // Benchmarks aren't expected to panic, so we run them all in-process.
 544             crate::bench::benchmark(id, desc, monitor_ch, opts.nocapture, benchfn);
 545             None
 546         }
 547         DynTestFn(f) => {
 548             match strategy {
 549                 RunStrategy::InProcess => (),
 550                 _ => panic!("Cannot run dynamic test fn out-of-process"),
 551             };
 552             run_test_inner(
 553                 id,
 554                 desc,
 555                 monitor_ch,
 556                 Box::new(move || __rust_begin_short_backtrace(f)),
 557                 test_run_opts,
 558             )
 559         }
 560         StaticTestFn(f) => run_test_inner(
 561             id,
 562             desc,
 563             monitor_ch,
 564             Box::new(move || __rust_begin_short_backtrace(f)),
 565             test_run_opts,
 566         ),
 567     }
 568 }
 569
 570 /// Fixed frame used to clean the backtrace with `RUST_BACKTRACE=1`.
 571 #[inline(never)]
 572 fn __rust_begin_short_backtrace<F: FnOnce()>(f: F) {
 573     f();
 574
 575     // prevent this frame from being tail-call optimised away
 576     black_box(());
 577 }
 578
 579 fn run_test_in_process(
 580     id: TestId,
 581     desc: TestDesc,
 582     nocapture: bool,
 583     report_time: bool,
 584     testfn: Box<dyn FnOnce() + Send>,
 585     monitor_ch: Sender<CompletedTest>,
 586     time_opts: Option<time::TestTimeOptions>,
 587 ) {
 588     // Buffer for capturing standard I/O
 589     let data = Arc::new(Mutex::new(Vec::new()));
 590
 591     if !nocapture {
 592         io::set_output_capture(Some(data.clone()));
 593     }
 594
 595     let start = report_time.then(Instant::now);
 596     let result = catch_unwind(AssertUnwindSafe(testfn));
 597     let exec_time = start.map(|start| {
 598         let duration = start.elapsed();
 599         TestExecTime(duration)
 600     });
 601
 602     io::set_output_capture(None);
 603
 604     let test_result = match result {
 605         Ok(()) => calc_result(&desc, Ok(()), &time_opts, &exec_time),
 606         Err(e) => calc_result(&desc, Err(e.as_ref()), &time_opts, &exec_time),
 607     };
 608     let stdout = data.lock().unwrap_or_else(|e| e.into_inner()).to_vec();
 609     let message = CompletedTest::new(id, desc, test_result, exec_time, stdout);
 610     monitor_ch.send(message).unwrap();
 611 }
 612
 613 fn spawn_test_subprocess(
 614     id: TestId,
 615     desc: TestDesc,
 616     nocapture: bool,
 617     report_time: bool,
 618     monitor_ch: Sender<CompletedTest>,
 619     time_opts: Option<time::TestTimeOptions>,
 620 ) {
 621     let (result, test_output, exec_time) = (|| {
 622         let args = env::args().collect::<Vec<_>>();
 623         let current_exe = &args[0];
 624
 625         let mut command = Command::new(current_exe);
 626         command.env(SECONDARY_TEST_INVOKER_VAR, desc.name.as_slice());
 627         if nocapture {
 628             command.stdout(process::Stdio::inherit());
 629             command.stderr(process::Stdio::inherit());
 630         }
 631
 632         let start = report_time.then(Instant::now);
 633         let output = match command.output() {
 634             Ok(out) => out,
 635             Err(e) => {
 636                 let err = format!("Failed to spawn {} as child for test: {:?}", args[0], e);
 637                 return (TrFailed, err.into_bytes(), None);
 638             }
 639         };
 640         let exec_time = start.map(|start| {
 641             let duration = start.elapsed();
 642             TestExecTime(duration)
 643         });
 644
 645         let std::process::Output { stdout, stderr, status } = output;
 646         let mut test_output = stdout;
 647         formatters::write_stderr_delimiter(&mut test_output, &desc.name);
 648         test_output.extend_from_slice(&stderr);
 649
 650         let result = match (|| -> Result<TestResult, String> {
 651             let exit_code = get_exit_code(status)?;
 652             Ok(get_result_from_exit_code(&desc, exit_code, &time_opts, &exec_time))
 653         })() {
 654             Ok(r) => r,
 655             Err(e) => {
 656                 write!(&mut test_output, "Unexpected error: {}", e).unwrap();
 657                 TrFailed
 658             }
 659         };
 660
 661         (result, test_output, exec_time)
 662     })();
 663
 664     let message = CompletedTest::new(id, desc, result, exec_time, test_output);
 665     monitor_ch.send(message).unwrap();
 666 }
 667
 668 fn run_test_in_spawned_subprocess(desc: TestDesc, testfn: Box<dyn FnOnce() + Send>) -> ! {
 669     let builtin_panic_hook = panic::take_hook();
 670     let record_result = Arc::new(move |panic_info: Option<&'_ PanicInfo<'_>>| {
 671         let test_result = match panic_info {
 672             Some(info) => calc_result(&desc, Err(info.payload()), &None, &None),
 673             None => calc_result(&desc, Ok(()), &None, &None),
 674         };
 675
 676         // We don't support serializing TrFailedMsg, so just
 677         // print the message out to stderr.
 678         if let TrFailedMsg(msg) = &test_result {
 679             eprintln!("{msg}");
 680         }
 681
 682         if let Some(info) = panic_info {
 683             builtin_panic_hook(info);
 684         }
 685
 686         if let TrOk = test_result {
 687             process::exit(test_result::TR_OK);
 688         } else {
 689             process::exit(test_result::TR_FAILED);
 690         }
 691     });
 692     let record_result2 = record_result.clone();
 693     panic::set_hook(Box::new(move |info| record_result2(Some(&info))));
 694     testfn();
 695     record_result(None);
 696     unreachable!("panic=abort callback should have exited the process")
 697 }