Skip to main content

mermaid_cli/domain/
cmd.rs

1//! Everything the reducer asks the outside world to do.
2//!
3//! `Cmd` values are inert data structures. The reducer returns them
4//! alongside each new `State`; `effect::EffectRunner::dispatch` then
5//! turns them into real work (spawning tokio tasks, writing files,
6//! hitting HTTP endpoints, killing processes). The reducer itself
7//! never performs any I/O.
8//!
9//! This is the "effects as data" pattern from Elm/Redux. Three
10//! payoffs this rewrite relies on:
11//!
12//!   1. **Testable reducer.** Assertions are `state, cmds = update(...)
13//!      ; assert_eq!(cmds[0], Cmd::CallModel { … })`. No tokio, no
14//!      mocks, no filesystem.
15//!   2. **Uniform middleware.** Retry, tracing, rate-limiting wrap the
16//!      dispatcher once instead of being re-implemented per adapter.
17//!   3. **Replayable sessions.** `--record` dumps every `Msg`; the
18//!      effects the reducer asked for are fully determined by the Msg
19//!      log + initial state, so `--replay` is a pure fold.
20
21use std::collections::HashMap;
22use std::path::PathBuf;
23
24use crate::app::McpServerConfig;
25use crate::models::ChatMessage;
26use crate::models::ReasoningLevel;
27use crate::models::tool_call::ToolCall as ModelToolCall;
28use crate::runtime::{SafetyMode, TaskStatus};
29use crate::session::ConversationHistory;
30
31use super::state::ApprovalChoice;
32
33use super::compaction::{CompactionArchive, CompactionRecord, CompactionRequest};
34use super::ids::{ToolCallId, TurnId};
35use super::runtime::ManagedProcess;
36
37/// A single side-effect request. Most variants are one-shot; `CallModel`
38/// and `ExecuteTool` spawn long-running tasks inside a per-turn
39/// `TurnScope`.
40// Several variants legitimately carry large payloads (a full
41// `ConversationHistory` / `ChatRequest`). Boxing them would churn ~20
42// construction + match sites for no real gain — `Cmd` values are short-lived
43// and moved, not stored in bulk.
44#[allow(clippy::large_enum_variant)]
45#[derive(Debug, Clone)]
46pub enum Cmd {
47    // ── Model + tool execution (the scope-spawning variants) ────────
48    /// Dispatch the next chat request. Effect runner maps this onto
49    /// `ModelProvider::chat` for the session's active provider.
50    CallModel { turn: TurnId, request: ChatRequest },
51    /// Generate a compact context checkpoint without continuing into
52    /// a normal assistant turn.
53    CompactConversation {
54        turn: TurnId,
55        request: CompactionRequest,
56    },
57    /// Run one tool in parallel with any other tools in the same turn.
58    /// The runner wires `ExecContext::token` to the turn's scope so
59    /// `Cmd::CancelScope` aborts them all at once.
60    ///
61    /// `model_id` is the active session's model id at the moment this
62    /// tool call was emitted. The runner passes it into `ExecContext`
63    /// so tools like `SubagentTool` can spawn children against the
64    /// same provider the parent is using.
65    ExecuteTool {
66        turn: TurnId,
67        call_id: ToolCallId,
68        source: ModelToolCall,
69        model_id: String,
70        /// Effective live safety mode (from `state.session.safety_mode`) at
71        /// the moment this call was emitted. The runner builds the policy
72        /// gate / Auto classifier from this rather than the static config.
73        safety_mode: SafetyMode,
74        /// The user's stated intent for the turn (latest user message),
75        /// passed to the Auto-mode classifier as alignment context.
76        intent: Option<String>,
77    },
78    /// Cancel every task in the given turn's `TurnScope`. After the
79    /// scope's `JoinSet` drains (bounded by a ~2s timeout), the runner
80    /// emits a single `Msg::TurnCancelled(turn)` — that, not
81    /// `Msg::StreamDone`, is the terminal event that lets the reducer
82    /// transition `Cancelling → Idle`. A same-id `Msg::StreamDone` that
83    /// races the drain does NOT end the turn: `handle_stream_done` only
84    /// acts on a `Generating` turn and restores the prior state
85    /// (`Cancelling`) otherwise, so `TurnCancelled` stays the one
86    /// terminal signal for a cancel.
87    CancelScope(TurnId),
88    /// Ctrl+B: signal the turn's scope to BACKGROUND (not cancel) its running
89    /// work. The scope's background token fires; detachable tools (execute_
90    /// command) move their child to a background process and return. The scope
91    /// is left intact (unlike `CancelScope`).
92    BackgroundScope(TurnId),
93
94    /// Resolve an inline approval prompt: deliver the user's decision to the
95    /// parked tool task via the `ApprovalBroker`. NOT turn-scoped — it's a
96    /// fire-and-forget to the broker (the tool task it unblocks is the
97    /// turn-scoped work).
98    ResolveApproval {
99        call_id: ToolCallId,
100        decision: ApprovalChoice,
101    },
102
103    // ── Persistence ─────────────────────────────────────────────────
104    /// Save the current conversation to disk. No-op if unchanged since
105    /// last save (effect-side idempotence).
106    SaveConversation(ConversationHistory),
107    /// Persist the raw messages removed by a compaction, then the compacted
108    /// (message-stripped) conversation. Both are written by ONE effect task,
109    /// archive first — only overwriting the conversation if the archive
110    /// persisted — so a failed/lagging archive can never lose messages while
111    /// the stripped conversation is saved over the old one.
112    SaveCompactionArchive {
113        archive: CompactionArchive,
114        record: CompactionRecord,
115        conversation: ConversationHistory,
116    },
117    /// Persist a daemon-visible background process record.
118    SaveProcess(ManagedProcess),
119    /// Persist the active model ID as `last_used_model`.
120    PersistLastModel(String),
121    /// Persist reasoning level tied to a specific model ID.
122    PersistReasoningFor {
123        model_id: String,
124        level: ReasoningLevel,
125    },
126    /// Persist (or clear, when `num_ctx` is `None`) a per-model Ollama `num_ctx`
127    /// override set via `/context <n>`/`max`/`auto`.
128    PersistOllamaNumCtxFor {
129        model_id: String,
130        num_ctx: Option<u32>,
131    },
132    /// Persist the Ollama RAM-offload toggle (`/context offload on|off`).
133    PersistOllamaOffload(bool),
134    /// List saved memories; emits `Msg::RuntimeText` with the rendered list.
135    ListMemory,
136    /// Save free-text to private memory; emits `Msg::MemoryChanged` + status.
137    RememberMemory { text: String },
138    /// Delete a memory by name/id; emits `Msg::MemoryChanged` + status.
139    ForgetMemory { id: String },
140    /// Model-assisted prune of duplicate/obsolete memories, reversible via a
141    /// checkpoint. Emits `Msg::RuntimeText` (the report) + `Msg::MemoryChanged`.
142    ConsolidateMemory { model_id: String },
143    /// Load a specific conversation by ID and emit
144    /// `Msg::ConversationLoaded`. Reducer consumes that event to
145    /// replace the current session.
146    LoadConversation(String),
147    /// Scan the conversations directory for the /load picker. Emits
148    /// `Msg::ConversationsListed` with one `ConversationSummary` per
149    /// saved session (newest first). The reducer transitions to
150    /// `UiMode::ConversationList` and the render shows the picker.
151    ListConversations,
152    /// List durable daemon/runtime tasks.
153    ListRuntimeTasks { limit: usize },
154    /// Load one durable daemon/runtime task and its timeline.
155    LoadRuntimeTask { id: String },
156    /// List durable daemon/runtime background processes.
157    ListRuntimeProcesses { limit: usize },
158    /// Print one durable process log into the conversation.
159    ShowRuntimeProcessLogs { id: String },
160    /// Stop a durable process by pid.
161    StopRuntimeProcess { id: String },
162    /// Restart a durable process using its recorded command/cwd.
163    RestartRuntimeProcess { id: String },
164    /// Open a URL, path, or process target.
165    OpenRuntimeTarget { target: String },
166    /// Show listening ports.
167    ShowRuntimePorts,
168    /// List pending approval records.
169    ListRuntimeApprovals,
170    /// Mark one approval as approved or denied.
171    DecideRuntimeApproval { id: String, decision: String },
172    /// List restore checkpoints.
173    ListRuntimeCheckpoints { limit: usize },
174    /// List installed plugins.
175    ListRuntimePlugins,
176    /// Update one durable task's status.
177    UpdateRuntimeTaskStatus {
178        id: String,
179        status: TaskStatus,
180        final_report: Option<String>,
181    },
182    /// Create a shadow checkpoint for explicit paths.
183    CreateRuntimeCheckpoint { paths: Vec<PathBuf> },
184    /// Restore files from a shadow checkpoint.
185    RestoreRuntimeCheckpoint { id: String },
186    /// Show provider/model capability information.
187    ShowRuntimeModelInfo { model: String },
188
189    // ── MCP lifecycle ───────────────────────────────────────────────
190    /// Start every configured MCP server; each one emits
191    /// `Msg::McpServerReady` or `Msg::McpServerErrored` as it comes up.
192    InitMcpServers(HashMap<String, McpServerConfig>),
193    /// Stop a running server (e.g. config was removed, or app quit).
194    StopMcpServer { name: String },
195
196    // ── Ollama helpers ──────────────────────────────────────────────
197    /// `ollama pull <model>` with progress → `Msg::ModelPullFinished`.
198    PullOllamaModel { model: String },
199
200    // ── UI side-effects (cross-process) ─────────────────────────────
201    /// `xdg-open` / `open` / `start` on a file path. Used by the
202    /// image-paste preview and the "open in editor" affordance.
203    OpenInSystem(PathBuf),
204
205    // ── Attachments ─────────────────────────────────────────────────
206    /// Persist a pasted image to a temp file so the TUI can open it
207    /// via `OpenInSystem`. Emits no follow-up Msg on success; failure
208    /// is a log-and-drop.
209    WriteImageToTemp {
210        path: PathBuf,
211        bytes: Vec<u8>,
212        format: String,
213    },
214
215    /// Read the system clipboard on a blocking task. The per-platform
216    /// dispatch (xclip / wl-paste / pngpaste / PowerShell) can block
217    /// for hundreds of ms on macOS via osascript, so it never runs on
218    /// the reducer thread. Emits `Msg::Paste(Paste::Image|Text)` on
219    /// success; `Msg::TransientStatus` when the clipboard is empty or
220    /// the read fails.
221    ReadClipboard,
222
223    /// Write text to the system clipboard on a blocking task (mirrors
224    /// `ReadClipboard`'s per-platform dispatch). Used by in-app drag-select
225    /// copy. Emits a `Msg::TransientStatus` ("Copied N chars" / failure).
226    CopyToClipboard(String),
227
228    // ── Terminal lifecycle ──────────────────────────────────────────
229    /// Exit the main loop. No reply message — the loop observes
230    /// `state.should_exit` after the reducer returns and breaks out.
231    Exit,
232    /// Write the OSC 2 terminal-title sequence. Reducer diffs
233    /// against `ui.last_title_dispatched` so this only fires on
234    /// actual title changes, not every frame.
235    SetTerminalTitle(String),
236}
237
238/// Inputs a model needs to generate a turn. Built by the reducer from
239/// `Session` + `Settings` + current `MERMAID.md` context. Pure data —
240/// no provider-specific knowledge here (that's in
241/// `providers::model::*::chat`).
242#[derive(Debug, Clone)]
243pub struct ChatRequest {
244    pub model_id: String,
245    pub messages: Vec<ChatMessage>,
246    pub system_prompt: String,
247    /// `MERMAID.md` content to suffix onto the system prompt. `None` if
248    /// no file was loaded for this project.
249    pub instructions: Option<String>,
250    pub reasoning: ReasoningLevel,
251    pub temperature: f32,
252    pub max_tokens: usize,
253    /// Tool definitions advertised to the model. Combination of the
254    /// built-in tool set + any advertised MCP tools from `McpState`.
255    pub tools: Vec<ToolDefinition>,
256    /// Per-model Ollama `num_ctx` override (`/context <n>`/`max`), or `None` to
257    /// auto-fit. The one provider-specific knob that rides on the request, the
258    /// same way `reasoning` does — so a live `/context` change applies on the
259    /// next turn without rebuilding the cached provider. Ignored by non-Ollama
260    /// providers.
261    pub ollama_num_ctx: Option<u32>,
262    /// Live Ollama RAM-offload toggle (`/context offload on|off`). Rides on the
263    /// request like `ollama_num_ctx` so a toggle applies on the next turn without
264    /// rebuilding the cached provider (whose `config` is frozen at startup).
265    /// `None` falls back to the persisted `[ollama] allow_ram_offload`. Ignored
266    /// by non-Ollama providers.
267    pub ollama_allow_ram_offload: Option<bool>,
268}
269
270/// Provider-agnostic tool definition sent in the request. Concrete
271/// adapters (`providers::model::ollama`, etc.) translate this into
272/// whatever wire shape their API expects.
273#[derive(Debug, Clone)]
274pub struct ToolDefinition {
275    pub name: String,
276    pub description: String,
277    pub input_schema: serde_json::Value,
278}
279
280impl ToolDefinition {
281    /// Wire shape: `{type: "function", function: {name, description,
282    /// parameters}}`. This is the OpenAI / Ollama Chat Completions
283    /// format; Anthropic and Gemini adapters translate further from
284    /// here. Single-canonical-shape keeps adapters from drifting.
285    pub fn to_openai_json(&self) -> serde_json::Value {
286        serde_json::json!({
287            "type": "function",
288            "function": {
289                "name": self.name,
290                "description": self.description,
291                "parameters": self.input_schema,
292            }
293        })
294    }
295}
296
297impl Cmd {
298    /// Human-readable tag, for tracing + replay logs. Stable across
299    /// refactors (tests assert against it).
300    pub fn tag(&self) -> &'static str {
301        match self {
302            Cmd::CallModel { .. } => "call_model",
303            Cmd::CompactConversation { .. } => "compact_conversation",
304            Cmd::ExecuteTool { .. } => "execute_tool",
305            Cmd::CancelScope(_) => "cancel_scope",
306            Cmd::BackgroundScope(_) => "background_scope",
307            Cmd::ResolveApproval { .. } => "resolve_approval",
308            Cmd::SaveConversation(_) => "save_conversation",
309            Cmd::SaveCompactionArchive { .. } => "save_compaction_archive",
310            Cmd::SaveProcess(_) => "save_process",
311            Cmd::PersistLastModel(_) => "persist_last_model",
312            Cmd::PersistReasoningFor { .. } => "persist_reasoning_for",
313            Cmd::PersistOllamaNumCtxFor { .. } => "persist_ollama_num_ctx_for",
314            Cmd::PersistOllamaOffload(_) => "persist_ollama_offload",
315            Cmd::ListMemory => "list_memory",
316            Cmd::RememberMemory { .. } => "remember_memory",
317            Cmd::ForgetMemory { .. } => "forget_memory",
318            Cmd::ConsolidateMemory { .. } => "consolidate_memory",
319            Cmd::LoadConversation(_) => "load_conversation",
320            Cmd::ListConversations => "list_conversations",
321            Cmd::ListRuntimeTasks { .. } => "list_runtime_tasks",
322            Cmd::LoadRuntimeTask { .. } => "load_runtime_task",
323            Cmd::ListRuntimeProcesses { .. } => "list_runtime_processes",
324            Cmd::ShowRuntimeProcessLogs { .. } => "show_runtime_process_logs",
325            Cmd::StopRuntimeProcess { .. } => "stop_runtime_process",
326            Cmd::RestartRuntimeProcess { .. } => "restart_runtime_process",
327            Cmd::OpenRuntimeTarget { .. } => "open_runtime_target",
328            Cmd::ShowRuntimePorts => "show_runtime_ports",
329            Cmd::ListRuntimeApprovals => "list_runtime_approvals",
330            Cmd::DecideRuntimeApproval { .. } => "decide_runtime_approval",
331            Cmd::ListRuntimeCheckpoints { .. } => "list_runtime_checkpoints",
332            Cmd::ListRuntimePlugins => "list_runtime_plugins",
333            Cmd::UpdateRuntimeTaskStatus { .. } => "update_runtime_task_status",
334            Cmd::CreateRuntimeCheckpoint { .. } => "create_runtime_checkpoint",
335            Cmd::RestoreRuntimeCheckpoint { .. } => "restore_runtime_checkpoint",
336            Cmd::ShowRuntimeModelInfo { .. } => "show_runtime_model_info",
337            Cmd::InitMcpServers(_) => "init_mcp_servers",
338            Cmd::StopMcpServer { .. } => "stop_mcp_server",
339            Cmd::PullOllamaModel { .. } => "pull_ollama_model",
340            Cmd::OpenInSystem(_) => "open_in_system",
341            Cmd::WriteImageToTemp { .. } => "write_image_to_temp",
342            Cmd::ReadClipboard => "read_clipboard",
343            Cmd::CopyToClipboard(_) => "copy_to_clipboard",
344            Cmd::Exit => "exit",
345            Cmd::SetTerminalTitle(_) => "set_terminal_title",
346        }
347    }
348
349    /// True iff this command needs to run inside a `TurnScope` so it
350    /// can be cancelled by `Cmd::CancelScope`. The effect runner uses
351    /// this to decide between "spawn into `JoinSet`" and "spawn detached".
352    pub fn is_turn_scoped(&self) -> bool {
353        matches!(
354            self,
355            Cmd::CallModel { .. } | Cmd::CompactConversation { .. } | Cmd::ExecuteTool { .. }
356        )
357    }
358
359    /// The `TurnId` of the scope this command would spawn fresh work
360    /// *into*. Only the scope-spawning variants return `Some` (the same
361    /// set as `is_turn_scoped`); the scope-control variants
362    /// (`CancelScope` / `BackgroundScope`) act on an existing scope
363    /// rather than populating one with new work, so they return `None`.
364    ///
365    /// The effect runner uses this to refuse spawning fresh work for a
366    /// turn it has already cancelled (tombstoned) — a stray post-cancel
367    /// `CallModel`/`ExecuteTool`/`CompactConversation` would otherwise
368    /// resurrect an un-cancelled scope via `scope_mut`'s `or_insert_with`
369    /// (F38). `CancelScope` must keep working on a tombstoned turn, which
370    /// is exactly why it is excluded here.
371    pub fn scope_turn(&self) -> Option<TurnId> {
372        match self {
373            Cmd::CallModel { turn, .. }
374            | Cmd::CompactConversation { turn, .. }
375            | Cmd::ExecuteTool { turn, .. } => Some(*turn),
376            _ => None,
377        }
378    }
379
380    /// For traces + the `--record` file — some `Cmd` payloads are huge
381    /// (think `ChatRequest::messages`). This returns a compact
382    /// identifier that doesn't dump the full payload.
383    pub fn summary(&self) -> String {
384        match self {
385            Cmd::CallModel { turn, request } => format!(
386                "call_model(turn={}, model={}, msgs={})",
387                turn,
388                request.model_id,
389                request.messages.len()
390            ),
391            Cmd::CompactConversation { turn, request } => format!(
392                "compact_conversation(turn={}, model={}, trigger={}, msgs={})",
393                turn,
394                request.chat.model_id,
395                request.trigger.as_str(),
396                request.chat.messages.len()
397            ),
398            Cmd::ExecuteTool {
399                turn,
400                call_id,
401                source,
402                ..
403            } => format!(
404                "execute_tool(turn={}, call={}, fn={})",
405                turn, call_id, source.function.name
406            ),
407            Cmd::CancelScope(turn) => format!("cancel_scope(turn={})", turn),
408            Cmd::BackgroundScope(turn) => format!("background_scope(turn={})", turn),
409            Cmd::ResolveApproval { call_id, decision } => {
410                format!("resolve_approval(call={}, {:?})", call_id, decision)
411            },
412            Cmd::SaveConversation(c) => format!("save_conversation(id={})", c.id),
413            Cmd::SaveCompactionArchive {
414                archive, record, ..
415            } => format!(
416                "save_compaction_archive(conversation={}, id={})",
417                archive.conversation_id, record.id
418            ),
419            Cmd::SaveProcess(p) => format!("save_process(id={}, pid={})", p.id, p.pid),
420            Cmd::PersistLastModel(m) => format!("persist_last_model({})", m),
421            Cmd::PersistReasoningFor { model_id, level } => {
422                format!("persist_reasoning_for({}, {:?})", model_id, level)
423            },
424            Cmd::PersistOllamaNumCtxFor { model_id, num_ctx } => {
425                format!("persist_ollama_num_ctx_for({}, {:?})", model_id, num_ctx)
426            },
427            Cmd::PersistOllamaOffload(enabled) => {
428                format!("persist_ollama_offload({})", enabled)
429            },
430            Cmd::ListMemory => "list_memory".to_string(),
431            Cmd::RememberMemory { .. } => "remember_memory".to_string(),
432            Cmd::ForgetMemory { .. } => "forget_memory".to_string(),
433            Cmd::ConsolidateMemory { .. } => "consolidate_memory".to_string(),
434            Cmd::LoadConversation(id) => format!("load_conversation({})", id),
435            Cmd::ListConversations => "list_conversations".to_string(),
436            Cmd::ListRuntimeTasks { limit } => format!("list_runtime_tasks(limit={})", limit),
437            Cmd::LoadRuntimeTask { id } => format!("load_runtime_task({})", id),
438            Cmd::ListRuntimeProcesses { limit } => {
439                format!("list_runtime_processes(limit={})", limit)
440            },
441            Cmd::ShowRuntimeProcessLogs { id } => format!("show_runtime_process_logs({})", id),
442            Cmd::StopRuntimeProcess { id } => format!("stop_runtime_process({})", id),
443            Cmd::RestartRuntimeProcess { id } => format!("restart_runtime_process({})", id),
444            Cmd::OpenRuntimeTarget { target } => format!("open_runtime_target({})", target),
445            Cmd::ShowRuntimePorts => "show_runtime_ports".to_string(),
446            Cmd::ListRuntimeApprovals => "list_runtime_approvals".to_string(),
447            Cmd::DecideRuntimeApproval { id, decision } => {
448                format!("decide_runtime_approval({}, {})", id, decision)
449            },
450            Cmd::ListRuntimeCheckpoints { limit } => {
451                format!("list_runtime_checkpoints(limit={})", limit)
452            },
453            Cmd::ListRuntimePlugins => "list_runtime_plugins".to_string(),
454            Cmd::UpdateRuntimeTaskStatus { id, status, .. } => {
455                format!("update_runtime_task_status({}, {})", id, status)
456            },
457            Cmd::CreateRuntimeCheckpoint { paths } => {
458                format!("create_runtime_checkpoint(n={})", paths.len())
459            },
460            Cmd::RestoreRuntimeCheckpoint { id } => format!("restore_runtime_checkpoint({})", id),
461            Cmd::ShowRuntimeModelInfo { model } => format!("show_runtime_model_info({})", model),
462            Cmd::InitMcpServers(m) => format!("init_mcp_servers(n={})", m.len()),
463            Cmd::StopMcpServer { name } => format!("stop_mcp_server({})", name),
464            Cmd::PullOllamaModel { model } => format!("pull_ollama_model({})", model),
465            Cmd::OpenInSystem(p) => format!("open_in_system({})", p.display()),
466            Cmd::WriteImageToTemp {
467                path,
468                format,
469                bytes,
470            } => format!(
471                "write_image_to_temp(path={}, fmt={}, n={})",
472                path.display(),
473                format,
474                bytes.len()
475            ),
476            Cmd::ReadClipboard => "read_clipboard".to_string(),
477            Cmd::CopyToClipboard(t) => format!("copy_to_clipboard(n={})", t.chars().count()),
478            Cmd::Exit => "exit".to_string(),
479            Cmd::SetTerminalTitle(t) => format!("set_terminal_title({})", t),
480        }
481    }
482}
483
484#[cfg(test)]
485mod tests {
486    use super::*;
487
488    #[test]
489    fn turn_scoped_variants_marked_correctly() {
490        let request = ChatRequest {
491            model_id: "m".to_string(),
492            messages: vec![],
493            system_prompt: String::new(),
494            instructions: None,
495            reasoning: ReasoningLevel::Medium,
496            temperature: 0.7,
497            max_tokens: 4096,
498            tools: vec![],
499
500            ollama_num_ctx: None,
501            ollama_allow_ram_offload: None,
502        };
503        assert!(
504            Cmd::CallModel {
505                turn: TurnId(1),
506                request,
507            }
508            .is_turn_scoped()
509        );
510        assert!(
511            !Cmd::SaveConversation(ConversationHistory::new(
512                "/p".to_string(),
513                "m".to_string(),
514                chrono::Local::now()
515            ))
516            .is_turn_scoped()
517        );
518        assert!(!Cmd::Exit.is_turn_scoped());
519    }
520
521    #[test]
522    fn cmd_tags_are_stable() {
523        assert_eq!(Cmd::Exit.tag(), "exit");
524        assert_eq!(Cmd::CancelScope(TurnId(1)).tag(), "cancel_scope");
525    }
526
527    #[test]
528    fn cmd_summary_includes_identifying_fields() {
529        let c = Cmd::CancelScope(TurnId(42));
530        let s = c.summary();
531        assert!(s.contains("turn#42"));
532    }
533}