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
  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(panic_can_unwind)]
  24 #![feature(test)]
  25
  26 // Public reexports
  27 pub use self::bench::{black_box, Bencher};
  28 pub use self::console::run_tests_console;
  29 pub use self::options::{ColorConfig, Options, OutputFormat, RunIgnored, ShouldPanic};
  30 pub use self::types::TestName::*;
  31 pub use self::types::*;
  32 pub use self::ColorConfig::*;
  33 pub use cli::TestOpts;
  34
  35 // Module to be used by rustc to compile tests in libtest
  36 pub mod test {
  37     pub use crate::{
  38         assert_test_result,
  39         bench::Bencher,
  40         cli::{parse_opts, TestOpts},
  41         filter_tests,
  42         helpers::metrics::{Metric, MetricMap},
  43         options::{Concurrent, Options, RunIgnored, RunStrategy, ShouldPanic},
  44         run_test, test_main, test_main_static,
  45         test_result::{TestResult, TrFailed, TrFailedMsg, TrIgnored, TrOk},
  46         time::{TestExecTime, TestTimeOptions},
  47         types::{
  48             DynTestFn, DynTestName, StaticBenchFn, StaticTestFn, StaticTestName, TestDesc,
  49             TestDescAndFn, TestId, TestName, TestType,
  50         },
  51     };
  52 }
  53
  54 use std::{
  55     collections::VecDeque,
  56     env, io,
  57     io::prelude::Write,
  58     mem::ManuallyDrop,
  59     panic::{self, catch_unwind, AssertUnwindSafe, PanicInfo},
  60     process::{self, Command, Termination},
  61     sync::mpsc::{channel, Sender},
  62     sync::{Arc, Mutex},
  63     thread,
  64     time::{Duration, Instant},
  65 };
  66
  67 pub mod bench;
  68 mod cli;
  69 mod console;
  70 mod event;
  71 mod formatters;
  72 mod helpers;
  73 mod options;
  74 pub mod stats;
  75 mod term;
  76 mod test_result;
  77 mod time;
  78 mod types;
  79
  80 #[cfg(test)]
  81 mod tests;
  82
  83 use core::any::Any;
  84 use event::{CompletedTest, TestEvent};
  85 use helpers::concurrency::get_concurrency;
  86 use helpers::exit_code::get_exit_code;
  87 use helpers::shuffle::{get_shuffle_seed, shuffle_tests};
  88 use options::{Concurrent, RunStrategy};
  89 use test_result::*;
  90 use time::TestExecTime;
  91
  92 // Process exit code to be used to indicate test failures.
  93 const ERROR_EXIT_CODE: i32 = 101;
  94
  95 const SECONDARY_TEST_INVOKER_VAR: &str = "__RUST_TEST_INVOKE";
  96
  97 // The default console test runner. It accepts the command line
  98 // arguments and a vector of test_descs.
  99 pub fn test_main(args: &[String], tests: Vec<TestDescAndFn>, options: Option<Options>) {
 100     let mut opts = match cli::parse_opts(args) {
 101         Some(Ok(o)) => o,
 102         Some(Err(msg)) => {
 103             eprintln!("error: {msg}");
 104             process::exit(ERROR_EXIT_CODE);
 105         }
 106         None => return,
 107     };
 108     if let Some(options) = options {
 109         opts.options = options;
 110     }
 111     if opts.list {
 112         if let Err(e) = console::list_tests_console(&opts, tests) {
 113             eprintln!("error: io error when listing tests: {e:?}");
 114             process::exit(ERROR_EXIT_CODE);
 115         }
 116     } else {
 117         if !opts.nocapture {
 118             // If we encounter a non-unwinding panic, flush any captured output from the current test,
 119             // and stop  capturing output to ensure that the non-unwinding panic message is visible.
 120             // We also acquire the locks for both output streams to prevent output from other threads
 121             // from interleaving with the panic message or appearing after it.
 122             let builtin_panic_hook = panic::take_hook();
 123             let hook = Box::new({
 124                 move |info: &'_ PanicInfo<'_>| {
 125                     if !info.can_unwind() {
 126                         std::mem::forget(std::io::stderr().lock());
 127                         let mut stdout = ManuallyDrop::new(std::io::stdout().lock());
 128                         if let Some(captured) = io::set_output_capture(None) {
 129                             if let Ok(data) = captured.lock() {
 130                                 let _ = stdout.write_all(&data);
 131                                 let _ = stdout.flush();
 132                             }
 133                         }
 134                     }
 135                     builtin_panic_hook(info);
 136                 }
 137             });
 138             panic::set_hook(hook);
 139         }
 140         match console::run_tests_console(&opts, tests) {
 141             Ok(true) => {}
 142             Ok(false) => process::exit(ERROR_EXIT_CODE),
 143             Err(e) => {
 144                 eprintln!("error: io error when listing tests: {e:?}");
 145                 process::exit(ERROR_EXIT_CODE);
 146             }
 147         }
 148     }
 149 }
 150
 151 /// A variant optimized for invocation with a static test vector.
 152 /// This will panic (intentionally) when fed any dynamic tests.
 153 ///
 154 /// This is the entry point for the main function generated by `rustc --test`
 155 /// when panic=unwind.
 156 pub fn test_main_static(tests: &[&TestDescAndFn]) {
 157     let args = env::args().collect::<Vec<_>>();
 158     let owned_tests: Vec<_> = tests.iter().map(make_owned_test).collect();
 159     test_main(&args, owned_tests, None)
 160 }
 161
 162 /// A variant optimized for invocation with a static test vector.
 163 /// This will panic (intentionally) when fed any dynamic tests.
 164 ///
 165 /// Runs tests in panic=abort mode, which involves spawning subprocesses for
 166 /// tests.
 167 ///
 168 /// This is the entry point for the main function generated by `rustc --test`
 169 /// when panic=abort.
 170 pub fn test_main_static_abort(tests: &[&TestDescAndFn]) {
 171     // If we're being run in SpawnedSecondary mode, run the test here. run_test
 172     // will then exit the process.
 173     if let Ok(name) = env::var(SECONDARY_TEST_INVOKER_VAR) {
 174         env::remove_var(SECONDARY_TEST_INVOKER_VAR);
 175         let test = tests
 176             .iter()
 177             .filter(|test| test.desc.name.as_slice() == name)
 178             .map(make_owned_test)
 179             .next()
 180             .unwrap_or_else(|| panic!("couldn't find a test with the provided name '{name}'"));
 181         let TestDescAndFn { desc, testfn } = test;
 182         let testfn = match testfn {
 183             StaticTestFn(f) => f,
 184             _ => panic!("only static tests are supported"),
 185         };
 186         run_test_in_spawned_subprocess(desc, Box::new(testfn));
 187     }
 188
 189     let args = env::args().collect::<Vec<_>>();
 190     let owned_tests: Vec<_> = tests.iter().map(make_owned_test).collect();
 191     test_main(&args, owned_tests, Some(Options::new().panic_abort(true)))
 192 }
 193
 194 /// Clones static values for putting into a dynamic vector, which test_main()
 195 /// needs to hand out ownership of tests to parallel test runners.
 196 ///
 197 /// This will panic when fed any dynamic tests, because they cannot be cloned.
 198 fn make_owned_test(test: &&TestDescAndFn) -> TestDescAndFn {
 199     match test.testfn {
 200         StaticTestFn(f) => TestDescAndFn { testfn: StaticTestFn(f), desc: test.desc.clone() },
 201         StaticBenchFn(f) => TestDescAndFn { testfn: StaticBenchFn(f), desc: test.desc.clone() },
 202         _ => panic!("non-static tests passed to test::test_main_static"),
 203     }
 204 }
 205
 206 /// Invoked when unit tests terminate. Returns `Result::Err` if the test is
 207 /// considered a failure. By default, invokes `report() and checks for a `0`
 208 /// result.
 209 pub fn assert_test_result<T: Termination>(result: T) -> Result<(), String> {
 210     let code = result.report().to_i32();
 211     if code == 0 {
 212         Ok(())
 213     } else {
 214         Err(format!(
 215             "the test returned a termination value with a non-zero status code \
 216              ({}) which indicates a failure",
 217             code
 218         ))
 219     }
 220 }
 221
 222 pub fn run_tests<F>(
 223     opts: &TestOpts,
 224     tests: Vec<TestDescAndFn>,
 225     mut notify_about_test_event: F,
 226 ) -> io::Result<()>
 227 where
 228     F: FnMut(TestEvent) -> io::Result<()>,
 229 {
 230     use std::collections::{self, HashMap};
 231     use std::hash::BuildHasherDefault;
 232     use std::sync::mpsc::RecvTimeoutError;
 233
 234     struct RunningTest {
 235         join_handle: Option<thread::JoinHandle<()>>,
 236     }
 237
 238     // Use a deterministic hasher
 239     type TestMap =
 240         HashMap<TestId, RunningTest, BuildHasherDefault<collections::hash_map::DefaultHasher>>;
 241
 242     struct TimeoutEntry {
 243         id: TestId,
 244         desc: TestDesc,
 245         timeout: Instant,
 246     }
 247
 248     let tests_len = tests.len();
 249
 250     let mut filtered_tests = filter_tests(opts, tests);
 251     if !opts.bench_benchmarks {
 252         filtered_tests = convert_benchmarks_to_tests(filtered_tests);
 253     }
 254
 255     let filtered_tests = {
 256         let mut filtered_tests = filtered_tests;
 257         for test in filtered_tests.iter_mut() {
 258             test.desc.name = test.desc.name.with_padding(test.testfn.padding());
 259         }
 260
 261         filtered_tests
 262     };
 263
 264     let filtered_out = tests_len - filtered_tests.len();
 265     let event = TestEvent::TeFilteredOut(filtered_out);
 266     notify_about_test_event(event)?;
 267
 268     let filtered_descs = filtered_tests.iter().map(|t| t.desc.clone()).collect();
 269
 270     let shuffle_seed = get_shuffle_seed(opts);
 271
 272     let event = TestEvent::TeFiltered(filtered_descs, shuffle_seed);
 273     notify_about_test_event(event)?;
 274
 275     let (mut filtered_tests, filtered_benchs): (Vec<_>, _) = filtered_tests
 276         .into_iter()
 277         .enumerate()
 278         .map(|(i, e)| (TestId(i), e))
 279         .partition(|(_, e)| matches!(e.testfn, StaticTestFn(_) | DynTestFn(_)));
 280
 281     let concurrency = opts.test_threads.unwrap_or_else(get_concurrency);
 282
 283     if let Some(shuffle_seed) = shuffle_seed {
 284         shuffle_tests(shuffle_seed, &mut filtered_tests);
 285     }
 286     // Store the tests in a VecDeque so we can efficiently remove the first element to run the
 287     // tests in the order they were passed (unless shuffled).
 288     let mut remaining = VecDeque::from(filtered_tests);
 289     let mut pending = 0;
 290
 291     let (tx, rx) = channel::<CompletedTest>();
 292     let run_strategy = if opts.options.panic_abort && !opts.force_run_in_process {
 293         RunStrategy::SpawnPrimary
 294     } else {
 295         RunStrategy::InProcess
 296     };
 297
 298     let mut running_tests: TestMap = HashMap::default();
 299     let mut timeout_queue: VecDeque<TimeoutEntry> = VecDeque::new();
 300
 301     fn get_timed_out_tests(
 302         running_tests: &TestMap,
 303         timeout_queue: &mut VecDeque<TimeoutEntry>,
 304     ) -> Vec<TestDesc> {
 305         let now = Instant::now();
 306         let mut timed_out = Vec::new();
 307         while let Some(timeout_entry) = timeout_queue.front() {
 308             if now < timeout_entry.timeout {
 309                 break;
 310             }
 311             let timeout_entry = timeout_queue.pop_front().unwrap();
 312             if running_tests.contains_key(&timeout_entry.id) {
 313                 timed_out.push(timeout_entry.desc);
 314             }
 315         }
 316         timed_out
 317     }
 318
 319     fn calc_timeout(timeout_queue: &VecDeque<TimeoutEntry>) -> Option<Duration> {
 320         timeout_queue.front().map(|&TimeoutEntry { timeout: next_timeout, .. }| {
 321             let now = Instant::now();
 322             if next_timeout >= now { next_timeout - now } else { Duration::new(0, 0) }
 323         })
 324     }
 325
 326     if concurrency == 1 {
 327         while !remaining.is_empty() {
 328             let (id, test) = remaining.pop_front().unwrap();
 329             let event = TestEvent::TeWait(test.desc.clone());
 330             notify_about_test_event(event)?;
 331             let join_handle =
 332                 run_test(opts, !opts.run_tests, id, test, run_strategy, tx.clone(), Concurrent::No);
 333             assert!(join_handle.is_none());
 334             let completed_test = rx.recv().unwrap();
 335
 336             let event = TestEvent::TeResult(completed_test);
 337             notify_about_test_event(event)?;
 338         }
 339     } else {
 340         while pending > 0 || !remaining.is_empty() {
 341             while pending < concurrency && !remaining.is_empty() {
 342                 let (id, test) = remaining.pop_front().unwrap();
 343                 let timeout = time::get_default_test_timeout();
 344                 let desc = test.desc.clone();
 345
 346                 let event = TestEvent::TeWait(desc.clone());
 347                 notify_about_test_event(event)?; //here no pad
 348                 let join_handle = run_test(
 349                     opts,
 350                     !opts.run_tests,
 351                     id,
 352                     test,
 353                     run_strategy,
 354                     tx.clone(),
 355                     Concurrent::Yes,
 356                 );
 357                 running_tests.insert(id, RunningTest { join_handle });
 358                 timeout_queue.push_back(TimeoutEntry { id, desc, timeout });
 359                 pending += 1;
 360             }
 361
 362             let mut res;
 363             loop {
 364                 if let Some(timeout) = calc_timeout(&timeout_queue) {
 365                     res = rx.recv_timeout(timeout);
 366                     for test in get_timed_out_tests(&running_tests, &mut timeout_queue) {
 367                         let event = TestEvent::TeTimeout(test);
 368                         notify_about_test_event(event)?;
 369                     }
 370
 371                     match res {
 372                         Err(RecvTimeoutError::Timeout) => {
 373                             // Result is not yet ready, continue waiting.
 374                         }
 375                         _ => {
 376                             // We've got a result, stop the loop.
 377                             break;
 378                         }
 379                     }
 380                 } else {
 381                     res = rx.recv().map_err(|_| RecvTimeoutError::Disconnected);
 382                     break;
 383                 }
 384             }
 385
 386             let mut completed_test = res.unwrap();
 387             let running_test = running_tests.remove(&completed_test.id).unwrap();
 388             if let Some(join_handle) = running_test.join_handle {
 389                 if let Err(_) = join_handle.join() {
 390                     if let TrOk = completed_test.result {
 391                         completed_test.result =
 392                             TrFailedMsg("panicked after reporting success".to_string());
 393                     }
 394                 }
 395             }
 396
 397             let event = TestEvent::TeResult(completed_test);
 398             notify_about_test_event(event)?;
 399             pending -= 1;
 400         }
 401     }
 402
 403     if opts.bench_benchmarks {
 404         // All benchmarks run at the end, in serial.
 405         for (id, b) in filtered_benchs {
 406             let event = TestEvent::TeWait(b.desc.clone());
 407             notify_about_test_event(event)?;
 408             run_test(opts, false, id, b, run_strategy, tx.clone(), Concurrent::No);
 409             let completed_test = rx.recv().unwrap();
 410
 411             let event = TestEvent::TeResult(completed_test);
 412             notify_about_test_event(event)?;
 413         }
 414     }
 415     Ok(())
 416 }
 417
 418 pub fn filter_tests(opts: &TestOpts, tests: Vec<TestDescAndFn>) -> Vec<TestDescAndFn> {
 419     let mut filtered = tests;
 420     let matches_filter = |test: &TestDescAndFn, filter: &str| {
 421         let test_name = test.desc.name.as_slice();
 422
 423         match opts.filter_exact {
 424             true => test_name == filter,
 425             false => test_name.contains(filter),
 426         }
 427     };
 428
 429     // Remove tests that don't match the test filter
 430     if !opts.filters.is_empty() {
 431         filtered.retain(|test| opts.filters.iter().any(|filter| matches_filter(test, filter)));
 432     }
 433
 434     // Skip tests that match any of the skip filters
 435     filtered.retain(|test| !opts.skip.iter().any(|sf| matches_filter(test, sf)));
 436
 437     // Excludes #[should_panic] tests
 438     if opts.exclude_should_panic {
 439         filtered.retain(|test| test.desc.should_panic == ShouldPanic::No);
 440     }
 441
 442     // maybe unignore tests
 443     match opts.run_ignored {
 444         RunIgnored::Yes => {
 445             filtered.iter_mut().for_each(|test| test.desc.ignore = false);
 446         }
 447         RunIgnored::Only => {
 448             filtered.retain(|test| test.desc.ignore);
 449             filtered.iter_mut().for_each(|test| test.desc.ignore = false);
 450         }
 451         RunIgnored::No => {}
 452     }
 453
 454     filtered
 455 }
 456
 457 pub fn convert_benchmarks_to_tests(tests: Vec<TestDescAndFn>) -> Vec<TestDescAndFn> {
 458     // convert benchmarks to tests, if we're not benchmarking them
 459     tests
 460         .into_iter()
 461         .map(|x| {
 462             let testfn = match x.testfn {
 463                 DynBenchFn(benchfn) => DynTestFn(Box::new(move || {
 464                     bench::run_once(|b| __rust_begin_short_backtrace(|| benchfn(b)))
 465                 })),
 466                 StaticBenchFn(benchfn) => DynTestFn(Box::new(move || {
 467                     bench::run_once(|b| __rust_begin_short_backtrace(|| benchfn(b)))
 468                 })),
 469                 f => f,
 470             };
 471             TestDescAndFn { desc: x.desc, testfn }
 472         })
 473         .collect()
 474 }
 475
 476 pub fn run_test(
 477     opts: &TestOpts,
 478     force_ignore: bool,
 479     id: TestId,
 480     test: TestDescAndFn,
 481     strategy: RunStrategy,
 482     monitor_ch: Sender<CompletedTest>,
 483     concurrency: Concurrent,
 484 ) -> Option<thread::JoinHandle<()>> {
 485     let TestDescAndFn { desc, testfn } = test;
 486
 487     // Emscripten can catch panics but other wasm targets cannot
 488     let ignore_because_no_process_support = desc.should_panic != ShouldPanic::No
 489         && cfg!(target_family = "wasm")
 490         && !cfg!(target_os = "emscripten");
 491
 492     if force_ignore || desc.ignore || ignore_because_no_process_support {
 493         let message = CompletedTest::new(id, desc, TrIgnored, None, Vec::new());
 494         monitor_ch.send(message).unwrap();
 495         return None;
 496     }
 497
 498     struct TestRunOpts {
 499         pub strategy: RunStrategy,
 500         pub nocapture: bool,
 501         pub concurrency: Concurrent,
 502         pub time: Option<time::TestTimeOptions>,
 503     }
 504
 505     fn run_test_inner(
 506         id: TestId,
 507         desc: TestDesc,
 508         monitor_ch: Sender<CompletedTest>,
 509         testfn: Box<dyn FnOnce() -> Result<(), String> + Send>,
 510         opts: TestRunOpts,
 511     ) -> Option<thread::JoinHandle<()>> {
 512         let concurrency = opts.concurrency;
 513         let name = desc.name.clone();
 514
 515         let runtest = move || match opts.strategy {
 516             RunStrategy::InProcess => run_test_in_process(
 517                 id,
 518                 desc,
 519                 opts.nocapture,
 520                 opts.time.is_some(),
 521                 testfn,
 522                 monitor_ch,
 523                 opts.time,
 524             ),
 525             RunStrategy::SpawnPrimary => spawn_test_subprocess(
 526                 id,
 527                 desc,
 528                 opts.nocapture,
 529                 opts.time.is_some(),
 530                 monitor_ch,
 531                 opts.time,
 532             ),
 533         };
 534
 535         // If the platform is single-threaded we're just going to run
 536         // the test synchronously, regardless of the concurrency
 537         // level.
 538         let supports_threads = !cfg!(target_os = "emscripten") && !cfg!(target_family = "wasm");
 539         if concurrency == Concurrent::Yes && supports_threads {
 540             let cfg = thread::Builder::new().name(name.as_slice().to_owned());
 541             let mut runtest = Arc::new(Mutex::new(Some(runtest)));
 542             let runtest2 = runtest.clone();
 543             match cfg.spawn(move || runtest2.lock().unwrap().take().unwrap()()) {
 544                 Ok(handle) => Some(handle),
 545                 Err(e) if e.kind() == io::ErrorKind::WouldBlock => {
 546                     // `ErrorKind::WouldBlock` means hitting the thread limit on some
 547                     // platforms, so run the test synchronously here instead.
 548                     Arc::get_mut(&mut runtest).unwrap().get_mut().unwrap().take().unwrap()();
 549                     None
 550                 }
 551                 Err(e) => panic!("failed to spawn thread to run test: {e}"),
 552             }
 553         } else {
 554             runtest();
 555             None
 556         }
 557     }
 558
 559     let test_run_opts =
 560         TestRunOpts { strategy, nocapture: opts.nocapture, concurrency, time: opts.time_options };
 561
 562     match testfn {
 563         DynBenchFn(benchfn) => {
 564             // Benchmarks aren't expected to panic, so we run them all in-process.
 565             crate::bench::benchmark(id, desc, monitor_ch, opts.nocapture, benchfn);
 566             None
 567         }
 568         StaticBenchFn(benchfn) => {
 569             // Benchmarks aren't expected to panic, so we run them all in-process.
 570             crate::bench::benchmark(id, desc, monitor_ch, opts.nocapture, benchfn);
 571             None
 572         }
 573         DynTestFn(f) => {
 574             match strategy {
 575                 RunStrategy::InProcess => (),
 576                 _ => panic!("Cannot run dynamic test fn out-of-process"),
 577             };
 578             run_test_inner(
 579                 id,
 580                 desc,
 581                 monitor_ch,
 582                 Box::new(move || __rust_begin_short_backtrace(f)),
 583                 test_run_opts,
 584             )
 585         }
 586         StaticTestFn(f) => run_test_inner(
 587             id,
 588             desc,
 589             monitor_ch,
 590             Box::new(move || __rust_begin_short_backtrace(f)),
 591             test_run_opts,
 592         ),
 593     }
 594 }
 595
 596 /// Fixed frame used to clean the backtrace with `RUST_BACKTRACE=1`.
 597 #[inline(never)]
 598 fn __rust_begin_short_backtrace<T, F: FnOnce() -> T>(f: F) -> T {
 599     let result = f();
 600
 601     // prevent this frame from being tail-call optimised away
 602     black_box(result)
 603 }
 604
 605 fn run_test_in_process(
 606     id: TestId,
 607     desc: TestDesc,
 608     nocapture: bool,
 609     report_time: bool,
 610     testfn: Box<dyn FnOnce() -> Result<(), String> + Send>,
 611     monitor_ch: Sender<CompletedTest>,
 612     time_opts: Option<time::TestTimeOptions>,
 613 ) {
 614     // Buffer for capturing standard I/O
 615     let data = Arc::new(Mutex::new(Vec::new()));
 616
 617     if !nocapture {
 618         io::set_output_capture(Some(data.clone()));
 619     }
 620
 621     let start = report_time.then(Instant::now);
 622     let result = fold_err(catch_unwind(AssertUnwindSafe(testfn)));
 623     let exec_time = start.map(|start| {
 624         let duration = start.elapsed();
 625         TestExecTime(duration)
 626     });
 627
 628     io::set_output_capture(None);
 629
 630     let test_result = match result {
 631         Ok(()) => calc_result(&desc, Ok(()), &time_opts, &exec_time),
 632         Err(e) => calc_result(&desc, Err(e.as_ref()), &time_opts, &exec_time),
 633     };
 634     let stdout = data.lock().unwrap_or_else(|e| e.into_inner()).to_vec();
 635     let message = CompletedTest::new(id, desc, test_result, exec_time, stdout);
 636     monitor_ch.send(message).unwrap();
 637 }
 638
 639 fn fold_err<T, E>(
 640     result: Result<Result<T, E>, Box<dyn Any + Send>>,
 641 ) -> Result<T, Box<dyn Any + Send>>
 642 where
 643     E: Send + 'static,
 644 {
 645     match result {
 646         Ok(Err(e)) => Err(Box::new(e)),
 647         Ok(Ok(v)) => Ok(v),
 648         Err(e) => Err(e),
 649     }
 650 }
 651
 652 fn spawn_test_subprocess(
 653     id: TestId,
 654     desc: TestDesc,
 655     nocapture: bool,
 656     report_time: bool,
 657     monitor_ch: Sender<CompletedTest>,
 658     time_opts: Option<time::TestTimeOptions>,
 659 ) {
 660     let (result, test_output, exec_time) = (|| {
 661         let args = env::args().collect::<Vec<_>>();
 662         let current_exe = &args[0];
 663
 664         let mut command = Command::new(current_exe);
 665         command.env(SECONDARY_TEST_INVOKER_VAR, desc.name.as_slice());
 666         if nocapture {
 667             command.stdout(process::Stdio::inherit());
 668             command.stderr(process::Stdio::inherit());
 669         }
 670
 671         let start = report_time.then(Instant::now);
 672         let output = match command.output() {
 673             Ok(out) => out,
 674             Err(e) => {
 675                 let err = format!("Failed to spawn {} as child for test: {:?}", args[0], e);
 676                 return (TrFailed, err.into_bytes(), None);
 677             }
 678         };
 679         let exec_time = start.map(|start| {
 680             let duration = start.elapsed();
 681             TestExecTime(duration)
 682         });
 683
 684         let std::process::Output { stdout, stderr, status } = output;
 685         let mut test_output = stdout;
 686         formatters::write_stderr_delimiter(&mut test_output, &desc.name);
 687         test_output.extend_from_slice(&stderr);
 688
 689         let result = match (|| -> Result<TestResult, String> {
 690             let exit_code = get_exit_code(status)?;
 691             Ok(get_result_from_exit_code(&desc, exit_code, &time_opts, &exec_time))
 692         })() {
 693             Ok(r) => r,
 694             Err(e) => {
 695                 write!(&mut test_output, "Unexpected error: {}", e).unwrap();
 696                 TrFailed
 697             }
 698         };
 699
 700         (result, test_output, exec_time)
 701     })();
 702
 703     let message = CompletedTest::new(id, desc, result, exec_time, test_output);
 704     monitor_ch.send(message).unwrap();
 705 }
 706
 707 fn run_test_in_spawned_subprocess(
 708     desc: TestDesc,
 709     testfn: Box<dyn FnOnce() -> Result<(), String> + Send>,
 710 ) -> ! {
 711     let builtin_panic_hook = panic::take_hook();
 712     let record_result = Arc::new(move |panic_info: Option<&'_ PanicInfo<'_>>| {
 713         let test_result = match panic_info {
 714             Some(info) => calc_result(&desc, Err(info.payload()), &None, &None),
 715             None => calc_result(&desc, Ok(()), &None, &None),
 716         };
 717
 718         // We don't support serializing TrFailedMsg, so just
 719         // print the message out to stderr.
 720         if let TrFailedMsg(msg) = &test_result {
 721             eprintln!("{msg}");
 722         }
 723
 724         if let Some(info) = panic_info {
 725             builtin_panic_hook(info);
 726         }
 727
 728         if let TrOk = test_result {
 729             process::exit(test_result::TR_OK);
 730         } else {
 731             process::exit(test_result::TR_FAILED);
 732         }
 733     });
 734     let record_result2 = record_result.clone();
 735     panic::set_hook(Box::new(move |info| record_result2(Some(&info))));
 736     if let Err(message) = testfn() {
 737         panic!("{}", message);
 738     }
 739     record_result(None);
 740     unreachable!("panic=abort callback should have exited the process")
 741 }