feat: b5-doctor-cmd — batch 5 upstream parity

rust/crates/commands/src/lib.rs

@@ -1188,6 +1188,9 @@ pub enum SlashCommand {
     AddDir {
         path: Option<String>,
     },
+    History {
+        count: Option<String>,
+    },
     Unknown(String),
 }
 
@@ -1421,6 +1424,9 @@ pub fn validate_slash_command_input(
         "tag" => SlashCommand::Tag { label: remainder },
         "output-style" => SlashCommand::OutputStyle { style: remainder },
         "add-dir" => SlashCommand::AddDir { path: remainder },
+        "history" => SlashCommand::History {
+            count: optional_single_arg(command, &args, "[count]")?,
+        },
         other => SlashCommand::Unknown(other.to_string()),
     }))
 }
@@ -3942,6 +3948,7 @@ pub fn handle_slash_command(
         | SlashCommand::Tag { .. }
         | SlashCommand::OutputStyle { .. }
         | SlashCommand::AddDir { .. }
+        | SlashCommand::History { .. }
         | SlashCommand::Unknown(_) => None,
     }
 }
@@ -4256,6 +4263,47 @@ mod tests {
         );
     }
 
+    #[test]
+    fn parses_history_command_without_count() {
+        // given
+        let input = "/history";
+
+        // when
+        let parsed = SlashCommand::parse(input);
+
+        // then
+        assert_eq!(parsed, Ok(Some(SlashCommand::History { count: None })));
+    }
+
+    #[test]
+    fn parses_history_command_with_numeric_count() {
+        // given
+        let input = "/history 25";
+
+        // when
+        let parsed = SlashCommand::parse(input);
+
+        // then
+        assert_eq!(
+            parsed,
+            Ok(Some(SlashCommand::History {
+                count: Some("25".to_string())
+            }))
+        );
+    }
+
+    #[test]
+    fn rejects_history_with_extra_arguments() {
+        // given
+        let input = "/history 25 extra";
+
+        // when
+        let error = parse_error_message(input);
+
+        // then
+        assert!(error.contains("Usage: /history [count]"));
+    }
+
     #[test]
     fn rejects_unexpected_arguments_for_no_arg_commands() {
         // given