rust/tests/ui/process/println-with-broken-pipe.rs
Martin Nordholts 075a6bbef9 Regression test println!() panic message on ErrorKind::BrokenPipe
No existing test failed if the [`panic!()`][1] of the `println!()`
family of functions was removed, or if its message was changed.

So add such a test.

[1] 104f4300cf/library/std/src/io/stdio.rs (L1007-L1009)
2023-07-26 13:41:39 +02:00

45 lines
1.3 KiB
Rust

// run-pass
// check-run-results
// ignore-windows
// ignore-emscripten
// ignore-fuchsia
// ignore-horizon
// ignore-android
// normalize-stderr-test ".rs:\d+:\d+" -> ".rs:LL:CC"
// Test what the error message looks like when `println!()` panics because of
// `std::io::ErrorKind::BrokenPipe`
#![feature(unix_sigpipe)]
use std::env;
use std::process::{Command, Stdio};
#[unix_sigpipe = "sig_ign"]
fn main() {
let mut args = env::args();
let me = args.next().unwrap();
if let Some(arg) = args.next() {
// More than enough iterations to fill any pipe buffer. Normally this
// loop will end with a panic more or less immediately.
for _ in 0..65536 * 64 {
println!("{arg}");
}
unreachable!("should have panicked because of BrokenPipe");
}
// Set up a pipeline with a short-lived consumer and wait for it to finish.
// This will produce the `println!()` panic message on stderr.
let mut producer = Command::new(&me)
.arg("this line shall appear exactly once on stdout")
.env("RUST_BACKTRACE", "0")
.stdout(Stdio::piped())
.spawn()
.unwrap();
let mut consumer =
Command::new("head").arg("-n1").stdin(producer.stdout.take().unwrap()).spawn().unwrap();
consumer.wait().unwrap();
producer.wait().unwrap();
}