test(worktree-isolation): add worktree detection tests

v2/bterminal-core/src/sidecar.rs

@@ -26,6 +26,8 @@ pub struct AgentQueryOptions {
     pub model: Option<String>,
     pub claude_config_dir: Option<String>,
     pub additional_directories: Option<Vec<String>>,
+    /// When set, agent runs in a git worktree for isolation (passed as --worktree <name> CLI flag)
+    pub worktree_name: Option<String>,
     /// Provider-specific configuration blob (passed through to sidecar as-is)
     #[serde(default)]
     pub provider_config: serde_json::Value,
@@ -216,6 +218,7 @@ impl SidecarManager {
             "model": options.model,
             "claudeConfigDir": options.claude_config_dir,
             "additionalDirectories": options.additional_directories,
+            "worktreeName": options.worktree_name,
             "providerConfig": options.provider_config,
         });
 

v2/sidecar/claude-runner.ts

@@ -48,6 +48,7 @@ interface QueryMessage {
   model?: string;
   claudeConfigDir?: string;
   additionalDirectories?: string[];
+  worktreeName?: string;
 }
 
 interface StopMessage {
@@ -72,7 +73,7 @@ async function handleMessage(msg: Record<string, unknown>) {
 }
 
 async function handleQuery(msg: QueryMessage) {
-  const { sessionId, prompt, cwd, maxTurns, maxBudgetUsd, resumeSessionId, permissionMode, settingSources, systemPrompt, model, claudeConfigDir, additionalDirectories } = msg;
+  const { sessionId, prompt, cwd, maxTurns, maxBudgetUsd, resumeSessionId, permissionMode, settingSources, systemPrompt, model, claudeConfigDir, additionalDirectories, worktreeName } = msg;
 
   if (sessions.has(sessionId)) {
     send({ type: 'error', sessionId, message: 'Session already running' });
@@ -126,6 +127,7 @@ async function handleQuery(msg: QueryMessage) {
           : { type: 'preset' as const, preset: 'claude_code' as const },
         model: model ?? undefined,
         additionalDirectories: additionalDirectories ?? undefined,
+        extraArgs: worktreeName ? { worktree: worktreeName } : undefined,
       },
     });
 

v2/src/lib/adapters/agent-bridge.ts

@@ -20,6 +20,8 @@ export interface AgentQueryOptions {
   model?: string;
   claude_config_dir?: string;
   additional_directories?: string[];
+  /** When set, agent runs in a git worktree for isolation */
+  worktree_name?: string;
   provider_config?: Record<string, unknown>;
   remote_machine_id?: string;
 }

v2/src/lib/agent-dispatcher.test.ts

@@ -205,6 +205,7 @@ import {
   isSidecarAlive,
   setSidecarAlive,
   waitForPendingPersistence,
+  detectWorktreeFromCwd,
 } from './agent-dispatcher';
 
 // Stop any previous dispatcher between tests so `unlistenMsg` is null and start works
@@ -622,4 +623,71 @@ describe('agent-dispatcher', () => {
       await expect(waitForPendingPersistence()).resolves.toBeUndefined();
     });
   });
+
+  describe('detectWorktreeFromCwd', () => {
+    it('detects Claude Code worktree path', () => {
+      const result = detectWorktreeFromCwd('/home/user/project/.claude/worktrees/my-session');
+      expect(result).toBe('/.claude/worktrees/my-session');
+    });
+
+    it('detects Codex worktree path', () => {
+      const result = detectWorktreeFromCwd('/home/user/project/.codex/worktrees/task-1');
+      expect(result).toBe('/.codex/worktrees/task-1');
+    });
+
+    it('detects Cursor worktree path', () => {
+      const result = detectWorktreeFromCwd('/home/user/project/.cursor/worktrees/feature-x');
+      expect(result).toBe('/.cursor/worktrees/feature-x');
+    });
+
+    it('returns null for non-worktree CWD', () => {
+      expect(detectWorktreeFromCwd('/home/user/project')).toBeNull();
+      expect(detectWorktreeFromCwd('/tmp/work')).toBeNull();
+    });
+
+    it('returns null for empty string', () => {
+      expect(detectWorktreeFromCwd('')).toBeNull();
+    });
+  });
+
+  describe('init event CWD worktree detection', () => {
+    beforeEach(async () => {
+      await startAgentDispatcher();
+    });
+
+    it('calls setSessionWorktree when init CWD contains worktree path', async () => {
+      const { setSessionWorktree } = await import('./stores/conflicts.svelte');
+
+      // Override the mock adapter to return init with worktree CWD
+      const { adaptMessage } = await import('./adapters/message-adapters');
+      (adaptMessage as ReturnType<typeof vi.fn>).mockReturnValueOnce([{
+        id: 'msg-wt',
+        type: 'init',
+        content: { sessionId: 'sdk-wt', model: 'claude-sonnet-4-20250514', cwd: '/home/user/repo/.claude/worktrees/my-session', tools: [] },
+        timestamp: Date.now(),
+      }]);
+
+      capturedCallbacks.msg!({
+        type: 'agent_event',
+        sessionId: 'sess-wt',
+        event: { type: 'system', subtype: 'init' },
+      });
+
+      expect(setSessionWorktree).toHaveBeenCalledWith('sess-wt', '/.claude/worktrees/my-session');
+    });
+
+    it('does not call setSessionWorktree for non-worktree CWD', async () => {
+      const { setSessionWorktree } = await import('./stores/conflicts.svelte');
+      (setSessionWorktree as ReturnType<typeof vi.fn>).mockClear();
+
+      capturedCallbacks.msg!({
+        type: 'agent_event',
+        sessionId: 'sess-normal',
+        event: { type: 'system', subtype: 'init' },
+      });
+
+      // The default mock returns cwd: '/tmp' which is not a worktree
+      expect(setSessionWorktree).not.toHaveBeenCalled();
+    });
+  });
 });

v2/src/lib/agent-dispatcher.ts

@@ -182,6 +182,14 @@ function handleAgentEvent(sessionId: string, event: Record<string, unknown>): vo
         const init = msg.content as InitContent;
         setAgentSdkSessionId(sessionId, init.sessionId);
         setAgentModel(sessionId, init.model);
+        // CWD-based worktree detection: if init CWD contains a worktree path pattern,
+        // register it for conflict suppression (agents in different worktrees don't conflict)
+        if (init.cwd) {
+          const wtPath = detectWorktreeFromCwd(init.cwd);
+          if (wtPath) {
+            setSessionWorktree(sessionId, wtPath);
+          }
+        }
         break;
       }
 
@@ -454,6 +462,22 @@ function triggerAutoAnchor(
   notify('info', `Anchored ${anchors.length} turns (${totalTokens} tokens) for context preservation`);
 }
 
+// Worktree path patterns for various providers
+const WORKTREE_CWD_PATTERNS = [
+  /\/\.claude\/worktrees\/([^/]+)/,    // Claude Code: <repo>/.claude/worktrees/<name>/
+  /\/\.codex\/worktrees\/([^/]+)/,     // Codex
+  /\/\.cursor\/worktrees\/([^/]+)/,    // Cursor
+];
+
+/** Extract worktree path from CWD if it matches a known worktree pattern */
+export function detectWorktreeFromCwd(cwd: string): string | null {
+  for (const pattern of WORKTREE_CWD_PATTERNS) {
+    const match = cwd.match(pattern);
+    if (match) return match[0]; // Return the full worktree path segment
+  }
+  return null;
+}
+
 export function stopAgentDispatcher(): void {
   if (unlistenMsg) {
     unlistenMsg();

v2/src/lib/components/Agent/AgentPane.svelte

@@ -53,10 +53,11 @@
     profile?: string;
     provider?: ProviderId;
     capabilities?: ProviderCapabilities;
+    useWorktrees?: boolean;
     onExit?: () => void;
   }
 
-  let { sessionId, projectId, prompt: initialPrompt = '', cwd: initialCwd, profile: profileName, provider: providerId = 'claude', capabilities = DEFAULT_CAPABILITIES, onExit }: Props = $props();
+  let { sessionId, projectId, prompt: initialPrompt = '', cwd: initialCwd, profile: profileName, provider: providerId = 'claude', capabilities = DEFAULT_CAPABILITIES, useWorktrees = false, onExit }: Props = $props();
 
   let session = $derived(getAgentSession(sessionId));
   let inputPrompt = $state(initialPrompt);
@@ -184,6 +185,7 @@
       setting_sources: ['user', 'project'],
       claude_config_dir: profile?.config_dir,
       system_prompt: systemPrompt,
+      worktree_name: useWorktrees ? sessionId : undefined,
     });
     inputPrompt = '';
     if (promptRef) {

v2/src/lib/components/Workspace/AgentSession.svelte

@@ -130,6 +130,7 @@
       profile={project.profile || undefined}
       provider={providerId}
       capabilities={providerMeta?.capabilities}
+      useWorktrees={project.useWorktrees ?? false}
       onExit={handleNewSession}
     />
   {/if}

v2/src/lib/components/Workspace/SettingsTab.svelte

@@ -793,6 +793,21 @@
               </div>
             </div>
 
+            <div class="card-field card-field-row">
+              <span class="card-field-label">
+                <svg width="12" height="12" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><path d="M6 3v12"/><path d="M18 9a3 3 0 0 0-3-3H7"/><path d="M18 9v12"/></svg>
+                Worktree Isolation
+              </span>
+              <label class="card-toggle" title={project.useWorktrees ? 'Worktrees enabled' : 'Worktrees disabled'}>
+                <input
+                  type="checkbox"
+                  checked={project.useWorktrees ?? false}
+                  onchange={e => updateProject(activeGroupId, project.id, { useWorktrees: (e.target as HTMLInputElement).checked })}
+                />
+                <span class="toggle-track"><span class="toggle-thumb"></span></span>
+              </label>
+            </div>
+
             <div class="card-footer">
               <button class="btn-remove" onclick={() => removeProject(activeGroupId, project.id)}>
                 <svg width="12" height="12" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><path d="M3 6h18"/><path d="M8 6V4h8v2"/><path d="M19 6v14a2 2 0 0 1-2 2H7a2 2 0 0 1-2-2V6"/></svg>
@@ -1200,6 +1215,12 @@
     gap: 0.25rem;
   }
 
+  .card-field.card-field-row {
+    flex-direction: row;
+    align-items: center;
+    justify-content: space-between;
+  }
+
   .card-field-label {
     display: flex;
     align-items: center;