Fix touch panics when using invalid timestamp (#6181)

Signed-off-by: nibon7 <nibon7@163.com>

crates/nu-command/src/filesystem/touch.rs

@@ -140,14 +140,24 @@ impl Command for Touch {
                         10 => Some(AddYear::Full),
                         12 => Some(AddYear::FirstDigits),
                         14 => None,
-                        _ => unreachable!(), // This should never happen as the check above should catch it
+                        _ => {
+                            return Err(ShellError::UnsupportedInput(
+                                "input has an invalid timestamp".to_string(),
+                                span,
+                            ))
+                        }
                     }
                 } else {
                     match size {
                         8 => Some(AddYear::Full),
                         10 => Some(AddYear::FirstDigits),
                         12 => None,
-                        _ => unreachable!(), // This should never happen as the check above should catch it
+                        _ => {
+                            return Err(ShellError::UnsupportedInput(
+                                "input has an invalid timestamp".to_string(),
+                                span,
+                            ))
+                        }
                     }
                 };
 

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

@@ -766,3 +766,20 @@ fn not_create_file_if_it_not_exists() {
         assert!(!path.exists());
     })
 }
+
+#[test]
+fn test_invalid_timestamp() {
+    Playground::setup("test_invalid_timestamp", |dirs, _sandbox| {
+        let outcome = nu!(
+            cwd: dirs.test(),
+            r#"touch -t 20220729. file.txt"#
+        );
+        assert!(outcome.err.contains("input has an invalid timestamp"));
+
+        let outcome = nu!(
+            cwd: dirs.test(),
+            r#"touch -t 20220729120099 file.txt"#
+        );
+        assert!(outcome.err.contains("input has an invalid timestamp"));
+    })
+}