Properly implement scarb::process::exec_replace

[mkaput]

Fix the TODO comment left there. Doc comment should fully describe what should happen internally.

scarb/scarb/src/process.rs

Lines 14 to 48 in 7bf281c

	// TODO(mkaput): Do what is documented here, take a look at what cargo-util does.
	/// Replaces the current process with the target process.
	///
	/// On Unix, this executes the process using the Unix syscall `execvp`, which will block this
	/// process, and will only return if there is an error.
	///
	/// On Windows this isn't technically possible. Instead we emulate it to the best of our ability.
	/// One aspect we fix here is that we specify a handler for the Ctrl-C handler.
	/// In doing so (and by effectively ignoring it) we should emulate proxying Ctrl-C handling to
	/// the application at hand, which will either terminate or handle it itself.
	/// According to Microsoft's documentation at
	/// <https://docs.microsoft.com/en-us/windows/console/ctrl-c-and-ctrl-break-signals>.
	/// the Ctrl-C signal is sent to all processes attached to a terminal, which should include our
	/// child process. If the child terminates then we'll reap them in Cargo pretty quickly, and if
	/// the child handles the signal then we won't terminate (and we shouldn't!) until the process
	/// itself later exits.
	#[tracing::instrument(level = "debug")]
	pub fn exec_replace(cmd: &mut Command) -> Result<()> {
	let exit_status = cmd
	.spawn()
	.with_context(|| format!("failed to spawn: {}", cmd.get_program().to_string_lossy()))?
	.wait()
	.with_context(|| {
	format!(
	"failed to wait for process to finish: {}",
	cmd.get_program().to_string_lossy()
	)
	})?;
	if exit_status.success() {
	Ok(())
	} else {
	bail!("process did not exit successfully: {exit_status}");
	}
	}