Improved error reporting and fully implemented the shopt command

src/builtin/shopt.rs

@@ -0,0 +1,30 @@
+use crate::{jobs::JobBldr, libsh::error::{ShResult, ShResultExt}, parse::{NdRule, Node}, prelude::*, procio::{borrow_fd, IoStack}, state::write_shopts};
+
+use super::setup_builtin;
+
+pub fn shopt(node: Node, io_stack: &mut IoStack, job: &mut JobBldr) -> ShResult<()> {
+	let NdRule::Command { assignments: _, argv } = node.class else {
+		unreachable!()
+	};
+
+	let (argv,io_frame) = setup_builtin(argv, job, Some((io_stack,node.redirs)))?;
+
+	let mut io_frame = io_frame.unwrap();
+	io_frame.redirect()?;
+	for (arg,span) in argv {
+		let Some(mut output) = write_shopts(|s| s.query(&arg)).blame(span)? else {
+			continue
+		};
+
+		let output_channel = borrow_fd(STDOUT_FILENO);
+		output.push('\n');
+
+		if let Err(e) = write(output_channel, output.as_bytes()) {
+			io_frame.restore()?;
+			return Err(e.into())
+		}
+	}
+	io_frame.restore()?;
+
+	Ok(())
+}