Merge pull request #10 from triarius/refactor-child

Refactor code to dedup running child process

src/lib.rs

@@ -9,7 +9,7 @@ use std::{
  io::{stderr, stdin, stdout, Read, Write},
  path::Path,
  process::{Command, Stdio},
- thread,
+ thread::{self, Scope},
 };
 
 fn io_streams<W: Write + Send + 'static>(
@@ -90,17 +90,7 @@ pub fn run(
  // joining on the tee thread.
  s.spawn(move || cancellable_tee(&r_cancel, &r_in, &mut in_writers[..]));
 
- if let Some(child_out) = child.stdout.take() {
- s.spawn(move || tee(child_out, &mut out_writers[..]));
- }
- if let Some(child_err) = child.stderr.take() {
- s.spawn(move || tee(child_err, &mut err_writers[..]));
- }
-
- let code = child
- .wait()?
- .code()
- .ok_or_else(|| eyre!("process terminated by signal"))?;
+ let code = run_with_output(s, child, &mut out_writers, &mut err_writers)?;
 
  // Cancel the tee threads. This may fail if the stdin was closed before the child process.
  t_cancel.try_send(()).flat_map_err(|e| match e {
@@ -111,20 +101,27 @@ pub fn run(
  Ok(code)
  })
  }
- None => thread::scope(|s| -> Result<i32> {
- if let Some(child_out) = child.stdout.take() {
- s.spawn(move || tee(child_out, &mut out_writers[..]));
- }
- if let Some(child_err) = child.stderr.take() {
- s.spawn(move || tee(child_err, &mut err_writers[..]));
- }
+ None => thread::scope(|s| run_with_output(s, child, &mut out_writers, &mut err_writers)),
+ }
+}
 
- child
- .wait()?
- .code()
- .ok_or_else(|| eyre!("process terminated by signal"))
- }),
+fn run_with_output<'a>(
+ s: &'a Scope<'a, '_>,
+ mut child: std::process::Child,
+ out_writers: &'a mut [Box<dyn Write + Send>],
+ err_writers: &'a mut [Box<dyn Write + Send>],
+) -> Result<i32> {
+ if let Some(child_out) = child.stdout.take() {
+ s.spawn(move || tee(child_out, &mut out_writers[..]));
  }
+ if let Some(child_err) = child.stderr.take() {
+ s.spawn(move || tee(child_err, &mut err_writers[..]));
+ }
+
+ child
+ .wait()?
+ .code()
+ .ok_or_else(|| eyre!("process terminated by signal"))
 }
 
 fn tee(mut stream: impl Read, outputs: &mut [Box<dyn Write + Send>]) -> Result<()> {