fix: windows e2e harness

e2e/app/build.rs

@@ -0,0 +1,20 @@
+fn main() {
+    // The harness links Donut as a library, and a dependency's link arguments
+    // never reach this binary. Without the Common Controls v6 manifest Windows
+    // loads comctl32 v5, and the app dies at startup with
+    // STATUS_ENTRYPOINT_NOT_FOUND (0xc0000139) before WebDriver can attach.
+    if std::env::var("CARGO_CFG_TARGET_OS").as_deref() == Ok("windows") {
+        let manifest_dir = std::path::PathBuf::from(std::env::var("CARGO_MANIFEST_DIR").unwrap());
+        let manifest = manifest_dir
+            .parent()
+            .and_then(|e2e| e2e.parent())
+            .expect("e2e/app sits two levels below the repository root")
+            .join("src-tauri")
+            .join("app.manifest");
+        // A plain backslash path: mt.exe rejects the \\?\ form canonicalize gives.
+        let manifest = manifest.to_str().unwrap().replace('/', "\\");
+        println!("cargo:rustc-link-arg=/MANIFEST:EMBED");
+        println!("cargo:rustc-link-arg=/MANIFESTINPUT:{manifest}");
+        println!("cargo:rerun-if-changed={manifest}");
+    }
+}

e2e/lib/app.mjs

@@ -123,6 +123,17 @@ export class AppSession {
       mkdir(path.join(this.root, "home"), { recursive: true }),
       mkdir(path.join(this.root, "tmp"), { recursive: true }),
       mkdir(path.join(this.root, "artifacts"), { recursive: true }),
+      // Windows expands the known folders from %USERPROFILE%, which points at
+      // the isolated home. A missing AppData\Roaming makes
+      // SHGetKnownFolderPath fail, and the app cannot resolve its base
+      // directories at startup.
+      ...(process.platform === "win32"
+        ? ["Roaming", "Local"].map((folder) =>
+            mkdir(path.join(this.root, "home", "AppData", folder), {
+              recursive: true,
+            }),
+          )
+        : []),
     ]);
     if (this.onboardingCompleted) {
       const settingsFile = path.join(

e2e/run.mjs

@@ -107,7 +107,17 @@ function log(message) {
 
 function run(command, args, cwd, env = process.env) {
   log(`${command} ${args.join(" ")}`);
-  const result = spawnSync(command, args, { cwd, env, stdio: "inherit" });
+  // pnpm is a .cmd shim on Windows, and Node starts those only through a
+  // shell. The arguments here are fixed words, so joining them is safe.
+  const result =
+    isWindows && command === "pnpm"
+      ? spawnSync([command, ...args].join(" "), {
+          cwd,
+          env,
+          stdio: "inherit",
+          shell: true,
+        })
+      : spawnSync(command, args, { cwd, env, stdio: "inherit" });
   if (result.error) {
     throw result.error;
   }