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 // N.B., this is also specified in this crate's Cargo.toml, but librustc_ast contains logic specific to
  17 // this crate, which relies on this attribute (rather than the value of `--crate-name` passed by
  18 // cargo) to detect this crate.
  19
  20 #![crate_name = "test"]
  21 #![unstable(feature = "test", issue = "50297")]
  22 #![doc(test(attr(deny(warnings))))]
  23 #![feature(libc)]
  24 #![feature(rustc_private)]
  25 #![feature(nll)]
  26 #![feature(available_parallelism)]
  27 #![feature(bench_black_box)]
  28 #![feature(internal_output_capture)]
  29 #![feature(panic_unwind)]
  30 #![feature(staged_api)]
  31 #![feature(termination_trait_lib)]
  32 #![feature(test)]
  33 #![feature(total_cmp)]
  34
  35 // Public reexports
  36 pub use self::bench::{black_box, Bencher};
  37 pub use self::console::run_tests_console;
  38 pub use self::options::{ColorConfig, Options, OutputFormat, RunIgnored, ShouldPanic};
  39 pub use self::types::TestName::*;
  40 pub use self::types::*;
  41 pub use self::ColorConfig::*;
  42 pub use cli::TestOpts;
  43
  44 // Module to be used by rustc to compile tests in libtest
  45 pub mod test {
  46     pub use crate::{
  47         assert_test_result,
  48         bench::Bencher,
  49         cli::{parse_opts, TestOpts},
  50         filter_tests,
  51         helpers::metrics::{Metric, MetricMap},
  52         options::{Concurrent, Options, RunIgnored, RunStrategy, ShouldPanic},
  53         run_test, test_main, test_main_static,
  54         test_result::{TestResult, TrFailed, TrFailedMsg, TrIgnored, TrOk},
  55         time::{TestExecTime, TestTimeOptions},
  56         types::{
  57             DynTestFn, DynTestName, StaticBenchFn, StaticTestFn, StaticTestName, TestDesc,
  58             TestDescAndFn, TestId, TestName, TestType,
  59         },
  60     };
  61 }
  62
  63 use std::{
  64     collections::VecDeque,
  65     env, io,
  66     io::prelude::Write,
  67     panic::{self, catch_unwind, AssertUnwindSafe, PanicInfo},
  68     process::{self, Command, Termination},
  69     sync::mpsc::{channel, Sender},
  70     sync::{Arc, Mutex},
  71     thread,
  72     time::{Duration, Instant},
  73 };
  74
  75 pub mod bench;
  76 mod cli;
  77 mod console;
  78 mod event;
  79 mod formatters;
  80 mod helpers;
  81 mod options;
  82 pub mod stats;
  83 mod term;
  84 mod test_result;
  85 mod time;
  86 mod types;
  87
  88 #[cfg(test)]
  89 mod tests;
  90
  91 use event::{CompletedTest, TestEvent};
  92 use helpers::concurrency::get_concurrency;
  93 use helpers::exit_code::get_exit_code;
  94 use helpers::shuffle::{get_shuffle_seed, shuffle_tests};
  95 use options::{Concurrent, RunStrategy};
  96 use test_result::*;
  97 use time::TestExecTime;
  98
  99 // Process exit code to be used to indicate test failures.
 100 const ERROR_EXIT_CODE: i32 = 101;
 101
 102 const SECONDARY_TEST_INVOKER_VAR: &str = "__RUST_TEST_INVOKE";
 103
 104 // The default console test runner. It accepts the command line
 105 // arguments and a vector of test_descs.
 106 pub fn test_main(args: &[String], tests: Vec<TestDescAndFn>, options: Option<Options>) {
 107     let mut opts = match cli::parse_opts(args) {
 108         Some(Ok(o)) => o,
 109         Some(Err(msg)) => {
 110             eprintln!("error: {}", msg);
 111             process::exit(ERROR_EXIT_CODE);
 112         }
 113         None => return,
 114     };
 115     if let Some(options) = options {
 116         opts.options = options;
 117     }
 118     if opts.list {
 119         if let Err(e) = console::list_tests_console(&opts, tests) {
 120             eprintln!("error: io error when listing tests: {:?}", e);
 121             process::exit(ERROR_EXIT_CODE);
 122         }
 123     } else {
 124         match console::run_tests_console(&opts, tests) {
 125             Ok(true) => {}
 126             Ok(false) => process::exit(ERROR_EXIT_CODE),
 127             Err(e) => {
 128                 eprintln!("error: io error when listing tests: {:?}", e);
 129                 process::exit(ERROR_EXIT_CODE);
 130             }
 131         }
 132     }
 133 }
 134
 135 /// A variant optimized for invocation with a static test vector.
 136 /// This will panic (intentionally) when fed any dynamic tests.
 137 ///
 138 /// This is the entry point for the main function generated by `rustc --test`
 139 /// when panic=unwind.
 140 pub fn test_main_static(tests: &[&TestDescAndFn]) {
 141     let args = env::args().collect::<Vec<_>>();
 142     let owned_tests: Vec<_> = tests.iter().map(make_owned_test).collect();
 143     test_main(&args, owned_tests, None)
 144 }
 145
 146 /// A variant optimized for invocation with a static test vector.
 147 /// This will panic (intentionally) when fed any dynamic tests.
 148 ///
 149 /// Runs tests in panic=abort mode, which involves spawning subprocesses for
 150 /// tests.
 151 ///
 152 /// This is the entry point for the main function generated by `rustc --test`
 153 /// when panic=abort.
 154 pub fn test_main_static_abort(tests: &[&TestDescAndFn]) {
 155     // If we're being run in SpawnedSecondary mode, run the test here. run_test
 156     // will then exit the process.
 157     if let Ok(name) = env::var(SECONDARY_TEST_INVOKER_VAR) {
 158         env::remove_var(SECONDARY_TEST_INVOKER_VAR);
 159         let test = tests
 160             .iter()
 161             .filter(|test| test.desc.name.as_slice() == name)
 162             .map(make_owned_test)
 163             .next()
 164             .unwrap_or_else(|| panic!("couldn't find a test with the provided name '{}'", name));
 165         let TestDescAndFn { desc, testfn } = test;
 166         let testfn = match testfn {
 167             StaticTestFn(f) => f,
 168             _ => panic!("only static tests are supported"),
 169         };
 170         run_test_in_spawned_subprocess(desc, Box::new(testfn));
 171     }
 172
 173     let args = env::args().collect::<Vec<_>>();
 174     let owned_tests: Vec<_> = tests.iter().map(make_owned_test).collect();
 175     test_main(&args, owned_tests, Some(Options::new().panic_abort(true)))
 176 }
 177
 178 /// Clones static values for putting into a dynamic vector, which test_main()
 179 /// needs to hand out ownership of tests to parallel test runners.
 180 ///
 181 /// This will panic when fed any dynamic tests, because they cannot be cloned.
 182 fn make_owned_test(test: &&TestDescAndFn) -> TestDescAndFn {
 183     match test.testfn {
 184         StaticTestFn(f) => TestDescAndFn { testfn: StaticTestFn(f), desc: test.desc.clone() },
 185         StaticBenchFn(f) => TestDescAndFn { testfn: StaticBenchFn(f), desc: test.desc.clone() },
 186         _ => panic!("non-static tests passed to test::test_main_static"),
 187     }
 188 }
 189
 190 /// Invoked when unit tests terminate. Should panic if the unit
 191 /// Tests is considered a failure. By default, invokes `report()`
 192 /// and checks for a `0` result.
 193 pub fn assert_test_result<T: Termination>(result: T) {
 194     let code = result.report();
 195     assert_eq!(
 196         code, 0,
 197         "the test returned a termination value with a non-zero status code ({}) \
 198          which indicates a failure",
 199         code
 200     );
 201 }
 202
 203 pub fn run_tests<F>(
 204     opts: &TestOpts,
 205     tests: Vec<TestDescAndFn>,
 206     mut notify_about_test_event: F,
 207 ) -> io::Result<()>
 208 where
 209     F: FnMut(TestEvent) -> io::Result<()>,
 210 {
 211     use std::collections::{self, HashMap};
 212     use std::hash::BuildHasherDefault;
 213     use std::sync::mpsc::RecvTimeoutError;
 214
 215     struct RunningTest {
 216         join_handle: Option<thread::JoinHandle<()>>,
 217     }
 218
 219     // Use a deterministic hasher
 220     type TestMap =
 221         HashMap<TestId, RunningTest, BuildHasherDefault<collections::hash_map::DefaultHasher>>;
 222
 223     struct TimeoutEntry {
 224         id: TestId,
 225         desc: TestDesc,
 226         timeout: Instant,
 227     }
 228
 229     let tests_len = tests.len();
 230
 231     let mut filtered_tests = filter_tests(opts, tests);
 232     if !opts.bench_benchmarks {
 233         filtered_tests = convert_benchmarks_to_tests(filtered_tests);
 234     }
 235
 236     let filtered_tests = {
 237         let mut filtered_tests = filtered_tests;
 238         for test in filtered_tests.iter_mut() {
 239             test.desc.name = test.desc.name.with_padding(test.testfn.padding());
 240         }
 241
 242         filtered_tests
 243     };
 244
 245     let filtered_out = tests_len - filtered_tests.len();
 246     let event = TestEvent::TeFilteredOut(filtered_out);
 247     notify_about_test_event(event)?;
 248
 249     let filtered_descs = filtered_tests.iter().map(|t| t.desc.clone()).collect();
 250
 251     let shuffle_seed = get_shuffle_seed(opts);
 252
 253     let event = TestEvent::TeFiltered(filtered_descs, shuffle_seed);
 254     notify_about_test_event(event)?;
 255
 256     let (filtered_tests, filtered_benchs): (Vec<_>, _) = filtered_tests
 257         .into_iter()
 258         .enumerate()
 259         .map(|(i, e)| (TestId(i), e))
 260         .partition(|(_, e)| matches!(e.testfn, StaticTestFn(_) | DynTestFn(_)));
 261
 262     let concurrency = opts.test_threads.unwrap_or_else(get_concurrency);
 263
 264     let mut remaining = filtered_tests;
 265     if let Some(shuffle_seed) = shuffle_seed {
 266         shuffle_tests(shuffle_seed, &mut remaining);
 267     } else {
 268         remaining.reverse();
 269     }
 270     let mut pending = 0;
 271
 272     let (tx, rx) = channel::<CompletedTest>();
 273     let run_strategy = if opts.options.panic_abort && !opts.force_run_in_process {
 274         RunStrategy::SpawnPrimary
 275     } else {
 276         RunStrategy::InProcess
 277     };
 278
 279     let mut running_tests: TestMap = HashMap::default();
 280     let mut timeout_queue: VecDeque<TimeoutEntry> = VecDeque::new();
 281
 282     fn get_timed_out_tests(
 283         running_tests: &TestMap,
 284         timeout_queue: &mut VecDeque<TimeoutEntry>,
 285     ) -> Vec<TestDesc> {
 286         let now = Instant::now();
 287         let mut timed_out = Vec::new();
 288         while let Some(timeout_entry) = timeout_queue.front() {
 289             if now < timeout_entry.timeout {
 290                 break;
 291             }
 292             let timeout_entry = timeout_queue.pop_front().unwrap();
 293             if running_tests.contains_key(&timeout_entry.id) {
 294                 timed_out.push(timeout_entry.desc);
 295             }
 296         }
 297         timed_out
 298     }
 299
 300     fn calc_timeout(timeout_queue: &VecDeque<TimeoutEntry>) -> Option<Duration> {
 301         timeout_queue.front().map(|&TimeoutEntry { timeout: next_timeout, .. }| {
 302             let now = Instant::now();
 303             if next_timeout >= now { next_timeout - now } else { Duration::new(0, 0) }
 304         })
 305     }
 306
 307     if concurrency == 1 {
 308         while !remaining.is_empty() {
 309             let (id, test) = remaining.pop().unwrap();
 310             let event = TestEvent::TeWait(test.desc.clone());
 311             notify_about_test_event(event)?;
 312             let join_handle =
 313                 run_test(opts, !opts.run_tests, id, test, run_strategy, tx.clone(), Concurrent::No);
 314             assert!(join_handle.is_none());
 315             let completed_test = rx.recv().unwrap();
 316
 317             let event = TestEvent::TeResult(completed_test);
 318             notify_about_test_event(event)?;
 319         }
 320     } else {
 321         while pending > 0 || !remaining.is_empty() {
 322             while pending < concurrency && !remaining.is_empty() {
 323                 let (id, test) = remaining.pop().unwrap();
 324                 let timeout = time::get_default_test_timeout();
 325                 let desc = test.desc.clone();
 326
 327                 let event = TestEvent::TeWait(desc.clone());
 328                 notify_about_test_event(event)?; //here no pad
 329                 let join_handle = run_test(
 330                     opts,
 331                     !opts.run_tests,
 332                     id,
 333                     test,
 334                     run_strategy,
 335                     tx.clone(),
 336                     Concurrent::Yes,
 337                 );
 338                 running_tests.insert(id, RunningTest { join_handle });
 339                 timeout_queue.push_back(TimeoutEntry { id, desc, timeout });
 340                 pending += 1;
 341             }
 342
 343             let mut res;
 344             loop {
 345                 if let Some(timeout) = calc_timeout(&timeout_queue) {
 346                     res = rx.recv_timeout(timeout);
 347                     for test in get_timed_out_tests(&running_tests, &mut timeout_queue) {
 348                         let event = TestEvent::TeTimeout(test);
 349                         notify_about_test_event(event)?;
 350                     }
 351
 352                     match res {
 353                         Err(RecvTimeoutError::Timeout) => {
 354                             // Result is not yet ready, continue waiting.
 355                         }
 356                         _ => {
 357                             // We've got a result, stop the loop.
 358                             break;
 359                         }
 360                     }
 361                 } else {
 362                     res = rx.recv().map_err(|_| RecvTimeoutError::Disconnected);
 363                     break;
 364                 }
 365             }
 366
 367             let mut completed_test = res.unwrap();
 368             let running_test = running_tests.remove(&completed_test.id).unwrap();
 369             if let Some(join_handle) = running_test.join_handle {
 370                 if let Err(_) = join_handle.join() {
 371                     if let TrOk = completed_test.result {
 372                         completed_test.result =
 373                             TrFailedMsg("panicked after reporting success".to_string());
 374                     }
 375                 }
 376             }
 377
 378             let event = TestEvent::TeResult(completed_test);
 379             notify_about_test_event(event)?;
 380             pending -= 1;
 381         }
 382     }
 383
 384     if opts.bench_benchmarks {
 385         // All benchmarks run at the end, in serial.
 386         for (id, b) in filtered_benchs {
 387             let event = TestEvent::TeWait(b.desc.clone());
 388             notify_about_test_event(event)?;
 389             run_test(opts, false, id, b, run_strategy, tx.clone(), Concurrent::No);
 390             let completed_test = rx.recv().unwrap();
 391
 392             let event = TestEvent::TeResult(completed_test);
 393             notify_about_test_event(event)?;
 394         }
 395     }
 396     Ok(())
 397 }
 398
 399 pub fn filter_tests(opts: &TestOpts, tests: Vec<TestDescAndFn>) -> Vec<TestDescAndFn> {
 400     let mut filtered = tests;
 401     let matches_filter = |test: &TestDescAndFn, filter: &str| {
 402         let test_name = test.desc.name.as_slice();
 403
 404         match opts.filter_exact {
 405             true => test_name == filter,
 406             false => test_name.contains(filter),
 407         }
 408     };
 409
 410     // Remove tests that don't match the test filter
 411     if !opts.filters.is_empty() {
 412         filtered.retain(|test| opts.filters.iter().any(|filter| matches_filter(test, filter)));
 413     }
 414
 415     // Skip tests that match any of the skip filters
 416     filtered.retain(|test| !opts.skip.iter().any(|sf| matches_filter(test, sf)));
 417
 418     // Excludes #[should_panic] tests
 419     if opts.exclude_should_panic {
 420         filtered.retain(|test| test.desc.should_panic == ShouldPanic::No);
 421     }
 422
 423     // maybe unignore tests
 424     match opts.run_ignored {
 425         RunIgnored::Yes => {
 426             filtered.iter_mut().for_each(|test| test.desc.ignore = false);
 427         }
 428         RunIgnored::Only => {
 429             filtered.retain(|test| test.desc.ignore);
 430             filtered.iter_mut().for_each(|test| test.desc.ignore = false);
 431         }
 432         RunIgnored::No => {}
 433     }
 434
 435     // Sort the tests alphabetically
 436     filtered.sort_by(|t1, t2| t1.desc.name.as_slice().cmp(t2.desc.name.as_slice()));
 437
 438     filtered
 439 }
 440
 441 pub fn convert_benchmarks_to_tests(tests: Vec<TestDescAndFn>) -> Vec<TestDescAndFn> {
 442     // convert benchmarks to tests, if we're not benchmarking them
 443     tests
 444         .into_iter()
 445         .map(|x| {
 446             let testfn = match x.testfn {
 447                 DynBenchFn(bench) => DynTestFn(Box::new(move || {
 448                     bench::run_once(|b| __rust_begin_short_backtrace(|| bench.run(b)))
 449                 })),
 450                 StaticBenchFn(benchfn) => DynTestFn(Box::new(move || {
 451                     bench::run_once(|b| __rust_begin_short_backtrace(|| benchfn(b)))
 452                 })),
 453                 f => f,
 454             };
 455             TestDescAndFn { desc: x.desc, testfn }
 456         })
 457         .collect()
 458 }
 459
 460 pub fn run_test(
 461     opts: &TestOpts,
 462     force_ignore: bool,
 463     id: TestId,
 464     test: TestDescAndFn,
 465     strategy: RunStrategy,
 466     monitor_ch: Sender<CompletedTest>,
 467     concurrency: Concurrent,
 468 ) -> Option<thread::JoinHandle<()>> {
 469     let TestDescAndFn { desc, testfn } = test;
 470
 471     // Emscripten can catch panics but other wasm targets cannot
 472     let ignore_because_no_process_support = desc.should_panic != ShouldPanic::No
 473         && cfg!(target_family = "wasm")
 474         && !cfg!(target_os = "emscripten");
 475
 476     if force_ignore || desc.ignore || ignore_because_no_process_support {
 477         let message = CompletedTest::new(id, desc, TrIgnored, None, Vec::new());
 478         monitor_ch.send(message).unwrap();
 479         return None;
 480     }
 481
 482     struct TestRunOpts {
 483         pub strategy: RunStrategy,
 484         pub nocapture: bool,
 485         pub concurrency: Concurrent,
 486         pub time: Option<time::TestTimeOptions>,
 487     }
 488
 489     fn run_test_inner(
 490         id: TestId,
 491         desc: TestDesc,
 492         monitor_ch: Sender<CompletedTest>,
 493         testfn: Box<dyn FnOnce() + Send>,
 494         opts: TestRunOpts,
 495     ) -> Option<thread::JoinHandle<()>> {
 496         let concurrency = opts.concurrency;
 497         let name = desc.name.clone();
 498
 499         let runtest = move || match opts.strategy {
 500             RunStrategy::InProcess => run_test_in_process(
 501                 id,
 502                 desc,
 503                 opts.nocapture,
 504                 opts.time.is_some(),
 505                 testfn,
 506                 monitor_ch,
 507                 opts.time,
 508             ),
 509             RunStrategy::SpawnPrimary => spawn_test_subprocess(
 510                 id,
 511                 desc,
 512                 opts.nocapture,
 513                 opts.time.is_some(),
 514                 monitor_ch,
 515                 opts.time,
 516             ),
 517         };
 518
 519         // If the platform is single-threaded we're just going to run
 520         // the test synchronously, regardless of the concurrency
 521         // level.
 522         let supports_threads = !cfg!(target_os = "emscripten") && !cfg!(target_family = "wasm");
 523         if concurrency == Concurrent::Yes && supports_threads {
 524             let cfg = thread::Builder::new().name(name.as_slice().to_owned());
 525             let mut runtest = Arc::new(Mutex::new(Some(runtest)));
 526             let runtest2 = runtest.clone();
 527             match cfg.spawn(move || runtest2.lock().unwrap().take().unwrap()()) {
 528                 Ok(handle) => Some(handle),
 529                 Err(e) if e.kind() == io::ErrorKind::WouldBlock => {
 530                     // `ErrorKind::WouldBlock` means hitting the thread limit on some
 531                     // platforms, so run the test synchronously here instead.
 532                     Arc::get_mut(&mut runtest).unwrap().get_mut().unwrap().take().unwrap()();
 533                     None
 534                 }
 535                 Err(e) => panic!("failed to spawn thread to run test: {}", e),
 536             }
 537         } else {
 538             runtest();
 539             None
 540         }
 541     }
 542
 543     let test_run_opts =
 544         TestRunOpts { strategy, nocapture: opts.nocapture, concurrency, time: opts.time_options };
 545
 546     match testfn {
 547         DynBenchFn(bencher) => {
 548             // Benchmarks aren't expected to panic, so we run them all in-process.
 549             crate::bench::benchmark(id, desc, monitor_ch, opts.nocapture, |harness| {
 550                 bencher.run(harness)
 551             });
 552             None
 553         }
 554         StaticBenchFn(benchfn) => {
 555             // Benchmarks aren't expected to panic, so we run them all in-process.
 556             crate::bench::benchmark(id, desc, monitor_ch, opts.nocapture, benchfn);
 557             None
 558         }
 559         DynTestFn(f) => {
 560             match strategy {
 561                 RunStrategy::InProcess => (),
 562                 _ => panic!("Cannot run dynamic test fn out-of-process"),
 563             };
 564             run_test_inner(
 565                 id,
 566                 desc,
 567                 monitor_ch,
 568                 Box::new(move || __rust_begin_short_backtrace(f)),
 569                 test_run_opts,
 570             )
 571         }
 572         StaticTestFn(f) => run_test_inner(
 573             id,
 574             desc,
 575             monitor_ch,
 576             Box::new(move || __rust_begin_short_backtrace(f)),
 577             test_run_opts,
 578         ),
 579     }
 580 }
 581
 582 /// Fixed frame used to clean the backtrace with `RUST_BACKTRACE=1`.
 583 #[inline(never)]
 584 fn __rust_begin_short_backtrace<F: FnOnce()>(f: F) {
 585     f();
 586
 587     // prevent this frame from being tail-call optimised away
 588     black_box(());
 589 }
 590
 591 fn run_test_in_process(
 592     id: TestId,
 593     desc: TestDesc,
 594     nocapture: bool,
 595     report_time: bool,
 596     testfn: Box<dyn FnOnce() + Send>,
 597     monitor_ch: Sender<CompletedTest>,
 598     time_opts: Option<time::TestTimeOptions>,
 599 ) {
 600     // Buffer for capturing standard I/O
 601     let data = Arc::new(Mutex::new(Vec::new()));
 602
 603     if !nocapture {
 604         io::set_output_capture(Some(data.clone()));
 605     }
 606
 607     let start = report_time.then(Instant::now);
 608     let result = catch_unwind(AssertUnwindSafe(testfn));
 609     let exec_time = start.map(|start| {
 610         let duration = start.elapsed();
 611         TestExecTime(duration)
 612     });
 613
 614     io::set_output_capture(None);
 615
 616     let test_result = match result {
 617         Ok(()) => calc_result(&desc, Ok(()), &time_opts, &exec_time),
 618         Err(e) => calc_result(&desc, Err(e.as_ref()), &time_opts, &exec_time),
 619     };
 620     let stdout = data.lock().unwrap_or_else(|e| e.into_inner()).to_vec();
 621     let message = CompletedTest::new(id, desc, test_result, exec_time, stdout);
 622     monitor_ch.send(message).unwrap();
 623 }
 624
 625 fn spawn_test_subprocess(
 626     id: TestId,
 627     desc: TestDesc,
 628     nocapture: bool,
 629     report_time: bool,
 630     monitor_ch: Sender<CompletedTest>,
 631     time_opts: Option<time::TestTimeOptions>,
 632 ) {
 633     let (result, test_output, exec_time) = (|| {
 634         let args = env::args().collect::<Vec<_>>();
 635         let current_exe = &args[0];
 636
 637         let mut command = Command::new(current_exe);
 638         command.env(SECONDARY_TEST_INVOKER_VAR, desc.name.as_slice());
 639         if nocapture {
 640             command.stdout(process::Stdio::inherit());
 641             command.stderr(process::Stdio::inherit());
 642         }
 643
 644         let start = report_time.then(Instant::now);
 645         let output = match command.output() {
 646             Ok(out) => out,
 647             Err(e) => {
 648                 let err = format!("Failed to spawn {} as child for test: {:?}", args[0], e);
 649                 return (TrFailed, err.into_bytes(), None);
 650             }
 651         };
 652         let exec_time = start.map(|start| {
 653             let duration = start.elapsed();
 654             TestExecTime(duration)
 655         });
 656
 657         let std::process::Output { stdout, stderr, status } = output;
 658         let mut test_output = stdout;
 659         formatters::write_stderr_delimiter(&mut test_output, &desc.name);
 660         test_output.extend_from_slice(&stderr);
 661
 662         let result = match (|| -> Result<TestResult, String> {
 663             let exit_code = get_exit_code(status)?;
 664             Ok(get_result_from_exit_code(&desc, exit_code, &time_opts, &exec_time))
 665         })() {
 666             Ok(r) => r,
 667             Err(e) => {
 668                 write!(&mut test_output, "Unexpected error: {}", e).unwrap();
 669                 TrFailed
 670             }
 671         };
 672
 673         (result, test_output, exec_time)
 674     })();
 675
 676     let message = CompletedTest::new(id, desc, result, exec_time, test_output);
 677     monitor_ch.send(message).unwrap();
 678 }
 679
 680 fn run_test_in_spawned_subprocess(desc: TestDesc, testfn: Box<dyn FnOnce() + Send>) -> ! {
 681     let builtin_panic_hook = panic::take_hook();
 682     let record_result = Arc::new(move |panic_info: Option<&'_ PanicInfo<'_>>| {
 683         let test_result = match panic_info {
 684             Some(info) => calc_result(&desc, Err(info.payload()), &None, &None),
 685             None => calc_result(&desc, Ok(()), &None, &None),
 686         };
 687
 688         // We don't support serializing TrFailedMsg, so just
 689         // print the message out to stderr.
 690         if let TrFailedMsg(msg) = &test_result {
 691             eprintln!("{}", msg);
 692         }
 693
 694         if let Some(info) = panic_info {
 695             builtin_panic_hook(info);
 696         }
 697
 698         if let TrOk = test_result {
 699             process::exit(test_result::TR_OK);
 700         } else {
 701             process::exit(test_result::TR_FAILED);
 702         }
 703     });
 704     let record_result2 = record_result.clone();
 705     panic::set_hook(Box::new(move |info| record_result2(Some(&info))));
 706     testfn();
 707     record_result(None);
 708     unreachable!("panic=abort callback should have exited the process")
 709 }