fix(useGitWatch): skip polling on non-git cwds (closes #62)

src/components/features/git/GitDiffPanel.tsx

@@ -6,6 +6,7 @@ import {
   gitUnstageFiles,
   type GitStatusResponse,
 } from '@/services/tauri';
+import { isGitRepo } from '@/services/tauri/git';
 import { useGitWatch } from '@/hooks/useGitWatch';
 import { useWorkspaceStore } from '@/stores';
 import { useLayoutStore } from '@/stores/settings';
@@ -41,6 +42,13 @@ export function GitDiffPanel({ cwd, isActive }: GitDiffPanelProps) {
 
   const refreshGitStatus = useCallback(async () => {
     if (!cwd) return;
+    // Non-git cwd: clear, don't error-flash. Same gate as useGitWatch.
+    if (!(await isGitRepo(cwd))) {
+      setGitData(null);
+      setGitError(null);
+      setGitLoading(false);
+      return;
+    }
     setGitLoading(true);
     setGitError(null);
     try {

src/hooks/useGitWatch.ts

@@ -1,6 +1,7 @@
 import { useEffect, useCallback, useRef } from 'react';
 import { listen, type UnlistenFn } from '@tauri-apps/api/event';
 import { startWatchFile, stopWatchFile } from '@/services/tauri/filesystem';
+import { isGitRepo } from '@/services/tauri/git';
 import { isDesktopTauri } from '@/hooks/runtime';
 
 /**
@@ -24,6 +25,7 @@ export function useGitWatch(cwd: string | null, onRefresh: () => void, enabled =
   useEffect(() => {
     if (!cwd || !enabled) return;
 
+    let cancelled = false;
     const gitIndexPath = `${cwd}/.git/index`;
     const normalizedGitIndexPath = gitIndexPath.replace(/\\/g, '/');
 
@@ -64,14 +66,22 @@ export function useGitWatch(cwd: string | null, onRefresh: () => void, enabled =
       }
     };
 
-    // Keep a low-frequency fallback for platforms where file events may be missed.
-    pollingRef.current = setInterval(() => {
-      debouncedRefresh();
-    }, 2500);
+    // Preflight: if cwd isn't a git repo, skip polling and watcher entirely.
+    // Otherwise consumers' refresh callbacks loop on errors every 2.5s.
+    const initialize = async () => {
+      if (!(await isGitRepo(cwd))) return;
+      if (cancelled) return;
+      // Keep a low-frequency fallback for platforms where file events may be missed.
+      pollingRef.current = setInterval(() => {
+        debouncedRefresh();
+      }, 2500);
+      void setupWatcher();
+    };
 
-    setupWatcher();
+    void initialize();
 
     return () => {
+      cancelled = true;
       if (unlistenRef.current) {
         unlistenRef.current();
         unlistenRef.current = null;

src/services/tauri/git.ts

@@ -1,4 +1,4 @@
-import { invokeTauri, isDesktopTauri, postJson, postNoContent } from './shared';
+import { invokeTauri, isDesktopTauri, postJson, postJsonWithOptions, postNoContent } from './shared';
 
 export type GitStatusEntry = {
   path: string;
@@ -66,6 +66,30 @@ export async function gitBranchInfo(cwd: string) {
   return await postJson<GitBranchInfoResponse>('/api/git/branch-info', { cwd });
 }
 
+// Returns true iff `cwd` is a git working tree. Used by useGitWatch and
+// downstream consumers to gate polling — non-git cwds otherwise loop on
+// errors. Hits the same backend endpoint as gitBranchInfo but passes
+// suppressToast so the shared API helper doesn't render a "Request failed"
+// toast on the (expected) non-git case. Result is not cached because cwd
+// changes are rare and the call is cheap.
+export async function isGitRepo(cwd: string): Promise<boolean> {
+  if (!cwd) return false;
+  try {
+    if (isDesktopTauri()) {
+      await invokeTauri<GitBranchInfoResponse>('git_branch_info', { cwd });
+    } else {
+      await postJsonWithOptions<GitBranchInfoResponse>(
+        '/api/git/branch-info',
+        { cwd },
+        { suppressToast: true },
+      );
+    }
+    return true;
+  } catch {
+    return false;
+  }
+}
+
 export async function gitListBranches(cwd: string) {
   if (isDesktopTauri()) {
     return await invokeTauri<GitBranchListResponse>('git_list_branches', { cwd });

src/stores/useGitStatsStore.ts

@@ -1,5 +1,6 @@
 import { create } from 'zustand';
 import { gitDiffStats, gitStatus } from '@/services/tauri';
+import { isGitRepo } from '@/services/tauri/git';
 
 interface GitStats {
   stagedFiles: number;
@@ -42,6 +43,13 @@ export const useGitStatsStore = create<GitStatsStore>((set) => ({
       return;
     }
 
+    // Non-git cwds (e.g. claude session that lived in $HOME) — render empty
+    // instead of error-flashing. Same gate as useGitWatch's polling.
+    if (!(await isGitRepo(cwd))) {
+      set({ stats: null });
+      return;
+    }
+
     set((state) => ({
       stats: state.stats ? { ...state.stats, isLoading: true } : { ...initialStats, isLoading: true },
     }));