Ignore UI test files in Vite dev watch

(cherry picked from commit c3d4e78e6f2038fd17cdd3f1cebb64a66489272b)

ui/src/lib/vite-watch.test.ts

@@ -0,0 +1,29 @@
+import { describe, expect, it } from "vitest";
+import { createUiDevWatchOptions, shouldIgnoreUiDevWatchPath } from "./vite-watch";
+
+describe("shouldIgnoreUiDevWatchPath", () => {
+  it("ignores test-only files and folders", () => {
+    expect(shouldIgnoreUiDevWatchPath("/repo/ui/src/components/IssuesList.test.tsx")).toBe(true);
+    expect(shouldIgnoreUiDevWatchPath("/repo/ui/src/lib/issue-tree.spec.ts")).toBe(true);
+    expect(shouldIgnoreUiDevWatchPath("/repo/ui/src/__tests__/helpers.ts")).toBe(true);
+    expect(shouldIgnoreUiDevWatchPath("/repo/ui/tests/helpers.ts")).toBe(true);
+  });
+
+  it("keeps runtime source files watchable", () => {
+    expect(shouldIgnoreUiDevWatchPath("/repo/ui/src/components/IssuesList.tsx")).toBe(false);
+    expect(shouldIgnoreUiDevWatchPath("/repo/ui/src/pages/IssueDetail.tsx")).toBe(false);
+  });
+});
+
+describe("createUiDevWatchOptions", () => {
+  it("preserves the WSL /mnt polling fallback", () => {
+    expect(createUiDevWatchOptions("/mnt/c/paperclip")).toMatchObject({
+      usePolling: true,
+      interval: 1000,
+    });
+  });
+
+  it("always includes the ignored-path predicate", () => {
+    expect(createUiDevWatchOptions("/Users/dotta/paperclip")).toHaveProperty("ignored");
+  });
+});

ui/src/lib/vite-watch.ts

@@ -0,0 +1,29 @@
+const TEST_DIRECTORY_NAMES = new Set([
+  "__tests__",
+  "_tests",
+  "test",
+  "tests",
+]);
+
+const TEST_FILE_BASENAME_RE = /\.(test|spec)\.[^/]+$/i;
+
+export function shouldIgnoreUiDevWatchPath(watchedPath: string): boolean {
+  const normalizedPath = String(watchedPath).replaceAll("\\", "/");
+  if (normalizedPath.length === 0) return false;
+
+  const segments = normalizedPath.split("/");
+  const basename = segments.at(-1) ?? normalizedPath;
+
+  return segments.some((segment) => TEST_DIRECTORY_NAMES.has(segment))
+    || TEST_FILE_BASENAME_RE.test(basename);
+}
+
+export function createUiDevWatchOptions(currentWorkingDirectory: string) {
+  return {
+    ignored: shouldIgnoreUiDevWatchPath,
+    // WSL2 /mnt/ drives don't support inotify — fall back to polling so HMR works.
+    ...(currentWorkingDirectory.startsWith("/mnt/")
+      ? { usePolling: true, interval: 1000 }
+      : {}),
+  };
+}

ui/vite.config.ts

@@ -2,6 +2,7 @@ import path from "path";
 import { defineConfig } from "vite";
 import react from "@vitejs/plugin-react";
 import tailwindcss from "@tailwindcss/vite";
+import { createUiDevWatchOptions } from "./src/lib/vite-watch";
 
 export default defineConfig({
   plugins: [react(), tailwindcss()],
@@ -13,8 +14,7 @@ export default defineConfig({
   },
   server: {
     port: 5173,
-    // WSL2 /mnt/ drives don't support inotify — fall back to polling so HMR works
-    watch: process.cwd().startsWith("/mnt/") ? { usePolling: true, interval: 1000 } : undefined,
+    watch: createUiDevWatchOptions(process.cwd()),
     proxy: {
       "/api": {
         target: "http://localhost:3100",