Include signal from terminated child process on unix

Author: tmandry

src/libtest/formatters/mod.rs

@@ -21,3 +21,12 @@ pub(crate) trait OutputFormatter {
     ) -> io::Result<()>;
     fn write_run_finish(&mut self, state: &ConsoleTestState) -> io::Result<bool>;
 }
+
+pub(crate) fn write_stderr_delimiter(test_output: &mut Vec<u8>, test_name: &TestName) {
+    match test_output.last() {
+        Some(b'\n') => (),
+        Some(_) => test_output.push(b'\n'),
+        None => (),
+    }
+    write!(test_output, "---- {} stderr ----\n", test_name).unwrap();
+}

src/libtest/lib.rs

@@ -56,7 +56,7 @@ use std::io::prelude::*;
 use std::panic::{self, catch_unwind, AssertUnwindSafe, PanicInfo};
 use std::path::PathBuf;
 use std::process;
-use std::process::{Command, Termination};
+use std::process::{ExitStatus, Command, Termination};
 use std::sync::mpsc::{channel, Sender};
 use std::sync::{Arc, Mutex};
 use std::thread;
@@ -1613,10 +1613,11 @@ fn spawn_test_subprocess(desc: TestDesc, monitor_ch: Sender<MonitorMsg>) {
 
         let std::process::Output { stdout, stderr, status } = output;
         let mut test_output = stdout;
+        formatters::write_stderr_delimiter(&mut test_output, &desc.name);
         test_output.extend_from_slice(&stderr);
 
         let result = match (move || {
-            let exit_code = status.code().ok_or("child process was terminated")?;
+            let exit_code = get_exit_code(status)?;
             TestResult::try_from(exit_code).map_err(|_| {
                 format!("child process returned unexpected exit code {}", exit_code)
             })
@@ -1664,6 +1665,23 @@ fn run_test_in_spawned_subprocess(desc: TestDesc, testfn: Box<dyn FnOnce() + Sen
     unreachable!("panic=abort callback should have exited the process")
 }
 
+#[cfg(not(unix))]
+fn get_exit_code(status: ExitStatus) -> Result<i32, String> {
+    status.code().ok_or("received no exit code from child process".into())
+}
+
+#[cfg(unix)]
+fn get_exit_code(status: ExitStatus) -> Result<i32, String> {
+    use std::os::unix::process::ExitStatusExt;
+    match status.code() {
+        Some(code) => Ok(code),
+        None => match status.signal() {
+            Some(signal) => Err(format!("child process exited with signal {}", signal)),
+            None => Err("child process exited with unknown signal".into()),
+        }
+    }
+}
+
 #[derive(Clone, PartialEq)]
 pub struct MetricMap(BTreeMap<String, Metric>);