implemented the 'builtin' and 'command' builtins

src/builtin/alias.rs

@@ -25,6 +25,16 @@ pub fn alias(node: Node, io_stack: &mut IoStack, job: &mut JobBldr) -> ShResult<
 		write(stdout, alias_output.as_bytes())?; // Write it
 	} else {
 		for (arg,span) in argv {
+			if arg == "command" || arg == "builtin" {
+				return Err(
+					ShErr::full(
+						ShErrKind::ExecFail,
+						format!("alias: Cannot assign alias to reserved name '{arg}'"),
+						span
+					)
+				)
+			}
+
 			let Some((name,body)) = arg.split_once('=') else {
 				return Err(
 					ShErr::full(

src/builtin/mod.rs

@@ -14,7 +14,7 @@ pub mod flowctl;
 pub mod zoltraak;
 pub mod shopt;
 
-pub const BUILTINS: [&str;17] = [
+pub const BUILTINS: [&str;19] = [
 	"echo",
 	"cd",
 	"export",
@@ -31,7 +31,9 @@ pub const BUILTINS: [&str;17] = [
 	"continue",
 	"exit",
 	"zoltraak",
-	"shopt"
+	"shopt",
+	"builtin",
+	"command"
 ];
 
 /// Sets up a builtin command

src/parse/execute.rs

@@ -345,9 +345,9 @@ impl Dispatcher {
 				write_vars(|v| v.set_var(&var.to_string(), &val.to_string(), false));
 			}
 
-			self.io_stack.push(body_frame.clone());
 
 			for node in body.clone() {
+				self.io_stack.push(body_frame.clone());
 				if let Err(e) = self.dispatch_node(node) {
 					match e.kind() {
 						ShErrKind::LoopBreak(code) => {
@@ -433,14 +433,22 @@ impl Dispatcher {
 		Ok(())
 	}
 	fn exec_builtin(&mut self, mut cmd: Node) -> ShResult<()> {
-		let NdRule::Command { ref mut assignments, argv: _ } = &mut cmd.class else {
+		let NdRule::Command { ref mut assignments, ref mut argv } = &mut cmd.class else {
 			unreachable!()
 		};
 		let env_vars_to_unset = self.set_assignments(mem::take(assignments), AssignBehavior::Export);
-		let cmd_raw = cmd.get_command().unwrap();
+		let cmd_raw = argv.first().unwrap();
 		let curr_job_mut = self.job_stack.curr_job_mut().unwrap();
 		let io_stack_mut = &mut self.io_stack;
 
+		if cmd_raw.as_str() == "builtin" || cmd_raw.as_str() == "command" {
+			*argv = argv.iter_mut()
+				.skip(1)
+				.map(|tk| tk.clone())
+				.collect::<Vec<Tk>>();
+			return self.dispatch_cmd(cmd)
+		}
+
 		flog!(TRACE, "doing builtin");
 		let result = match cmd_raw.span.as_str() {
 			"echo" => echo(cmd, io_stack_mut, curr_job_mut),