Restrict short-hand flag detection to exact match. (#1406)

crates/nu-parser/src/parse/token_tree.rs

@@ -368,8 +368,13 @@ impl SpannedToken {
 
                 match flag.kind {
                     FlagKind::Longhand if value == name => Some(*flag),
-                    FlagKind::Shorthand if short.is_some() && short == name.chars().next() => {
+                    FlagKind::Shorthand => {
-                        Some(*flag)
+                        if let Some(short_hand) = short {
+                            if short_hand.to_string() == name {
+                                return Some(*flag);
+                            }
+                        }
+                        None
                     }
                     _ => None,
                 }

tests/shell/pipeline/commands/internal.rs

@@ -56,6 +56,29 @@ mod parse {
         -r, --raw: Prints the raw value representation.
     */
 
+    #[test]
+    fn errors_if_flag_passed_is_not_exact() {
+        let actual = nu_error!(cwd: ".", "debug -ra");
+
+        assert!(
+            actual.contains("unexpected flag"),
+            format!(
+                "error message '{}' should contain 'unexpected flag'",
+                actual
+            )
+        );
+
+        let actual = nu_error!(cwd: ".", "debug --rawx");
+
+        assert!(
+            actual.contains("unexpected flag"),
+            format!(
+                "error message '{}' should contain 'unexpected flag'",
+                actual
+            )
+        );
+    }
+
     #[test]
     fn errors_if_flag_is_not_supported() {
         let actual = nu_error!(cwd: ".", "debug --ferris");