escape external args (#6560)

crates/nu-command/tests/commands/run_external.rs

@@ -186,6 +186,20 @@ fn external_arg_with_variable_name() {
     })
 }
 
+#[test]
+fn external_command_escape_args() {
+    Playground::setup("external failed command with semicolon", |dirs, _| {
+        let actual = nu!(
+            cwd: dirs.test(), pipeline(
+            r#"
+                ^echo "\"abcd"
+            "#
+        ));
+
+        assert_eq!(actual.out, r#""abcd"#);
+    })
+}
+
 #[cfg(windows)]
 #[test]
 fn explicit_glob_windows() {

crates/nu-parser/src/parser.rs

@@ -331,7 +331,13 @@ pub fn parse_external_call(
             args.push(arg);
         } else {
             // Eval stage trims the quotes, so we don't have to do the same thing when parsing.
-            let contents = String::from_utf8_lossy(contents).to_string();
+            let contents = if contents.starts_with(b"\"") {
+                let (contents, err) = unescape_string(contents, *span);
+                error = error.or(err);
+                String::from_utf8_lossy(&contents).to_string()
+            } else {
+                String::from_utf8_lossy(contents).to_string()
+            };
 
             args.push(Expression {
                 expr: Expr::String(contents),