Implemented scoping for expansions

src/builtin/echo.rs

@@ -2,52 +2,82 @@ use shellenv::jobs::{ChildProc, JobBldr};
 
 use crate::prelude::*;
 
+bitflags! {
+	#[derive(Debug,Clone,Copy)]
+	pub struct EchoFlags: u32 {
+		const USE_ESCAPE = 0b0001;
+		const NO_ESCAPE  = 0b0010;
+		const STDERR     = 0b0100;
+		const NO_NEWLINE = 0b1000;
+	}
+}
+
 pub fn echo(node: Node, shenv: &mut ShEnv) -> ShResult<()> {
 	let rule = node.into_rule();
 
 	if let NdRule::Command { argv, redirs } = rule {
-		let argv = argv.drop_first().as_strings(shenv);
-		let mut formatted = argv.join(" ");
-		formatted.push('\n');
-
-		if shenv.ctx().flags().contains(ExecFlags::NO_FORK) {
-			shenv.collect_redirs(redirs);
-			if let Err(e) = shenv.ctx_mut().activate_rdrs() {
-				eprintln!("{:?}",e);
-				exit(1);
-			}
-			if let Err(e) = write_out(formatted) {
-				eprintln!("{:?}",e);
-				exit(1);
-			}
-			exit(0);
-		} else {
-			match unsafe { fork()? } {
-				Child => {
-					shenv.collect_redirs(redirs);
-					if let Err(e) = shenv.ctx_mut().activate_rdrs() {
-						eprintln!("{:?}",e);
-						exit(1);
+		let mut argv_iter = argv.into_iter().skip(1).peekable();
+		let mut echo_flags = EchoFlags::empty();
+		while let Some(arg) = argv_iter.peek() {
+			let blame = arg.span();
+			let raw = arg.as_raw(shenv);
+			if raw.starts_with('-') {
+				let _ = argv_iter.next();
+				let mut options = raw.strip_prefix('-').unwrap().chars();
+				while let Some(opt) = options.next() {
+					match opt {
+						'r' => echo_flags |= EchoFlags::STDERR,
+						'n' => echo_flags |= EchoFlags::NO_NEWLINE,
+						'e' => {
+							if echo_flags.contains(EchoFlags::NO_ESCAPE) {
+								return Err(
+									ShErr::full(
+										ShErrKind::ExecFail,
+										"the 'e' and 'E' flags are mutually exclusive",
+										shenv.get_input(),
+										blame
+									)
+								)
+							}
+							echo_flags |= EchoFlags::USE_ESCAPE;
+						}
+						'E' => {
+							if echo_flags.contains(EchoFlags::USE_ESCAPE) {
+								return Err(
+									ShErr::full(
+										ShErrKind::ExecFail,
+										"the 'e' and 'E' flags are mutually exclusive",
+										shenv.get_input(),
+										blame
+									)
+								)
+							}
+							echo_flags |= EchoFlags::NO_ESCAPE;
+						}
+						_ => return Err(
+							ShErr::full(
+								ShErrKind::ExecFail,
+								format!("Unrecognized echo option"),
+								shenv.get_input(),
+								blame
+							)
+						)
 					}
-					if let Err(e) = write_out(formatted) {
-						eprintln!("{:?}",e);
-						exit(1);
-					}
-					exit(0);
-				}
-				Parent { child } => {
-					shenv.reset_io()?;
-					let children = vec![
-						ChildProc::new(child, Some("echo"), Some(child))?
-					];
-					let job = JobBldr::new()
-						.with_children(children)
-						.with_pgid(child)
-						.build();
-					wait_fg(job, shenv)?;
 				}
+			} else {
+				break
 			}
 		}
+		let argv = argv_iter.collect::<Vec<_>>().as_strings(shenv);
+		let mut formatted = argv.join(" ");
+		if !echo_flags.contains(EchoFlags::NO_NEWLINE) {
+			formatted.push('\n');
+		}
+
+		shenv.collect_redirs(redirs);
+		shenv.ctx_mut().activate_rdrs()?;
+		write_out(formatted)?;
+
 	} else { unreachable!() }
 	Ok(())
 }