From 3cbd69bc7f30885a5ca5afcbf9fae2d069fdd74c Mon Sep 17 00:00:00 2001
From: Dan Nyanko <dan.nyanko@gmail.com>
Date: Mon, 24 Aug 2026 08:15:08 -0400
Subject: [PATCH] fix(tests): polyfill localStorage in jsdom test setup

jsdom does not reliably expose localStorage across runtimes (e.g. Node 26's
experimental built-in shadows it), causing projectsPersistence/projectsSlice
tests to fail with 'localStorage is undefined'. Add a minimal in-memory shim
guarded by typeof check so it only applies when absent, keeping behavior
identical on environments where jsdom already provides it.
---
 src/test/setup.ts | 40 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/src/test/setup.ts b/src/test/setup.ts
index e9083a3..b366e2a 100644
--- a/src/test/setup.ts
+++ b/src/test/setup.ts
@@ -1,3 +1,43 @@
+// jsdom does not reliably expose `localStorage` across environments (e.g. on
+// Node 26 its experimental built-in `localStorage` shadows the jsdom one, so
+// `localStorage` is undefined in tests). Provide a minimal in-memory shim so
+// tests that rely on `localStorage` run consistently regardless of the runtime.
+if (typeof globalThis.localStorage === 'undefined') {
+  class MemoryStorage {
+    private store = new Map<string, string>();
+
+    get length(): number {
+      return this.store.size;
+    }
+
+    key(index: number): string | null {
+      return Array.from(this.store.keys())[index] ?? null;
+    }
+
+    getItem(key: string): string | null {
+      return this.store.get(key) ?? null;
+    }
+
+    setItem(key: string, value: string): void {
+      this.store.set(key, String(value));
+    }
+
+    removeItem(key: string): void {
+      this.store.delete(key);
+    }
+
+    clear(): void {
+      this.store.clear();
+    }
+  }
+
+  const storage = new MemoryStorage();
+  globalThis.localStorage = storage as unknown as Storage;
+  if (typeof window !== 'undefined') {
+    window.localStorage = storage as unknown as Storage;
+  }
+}
+
 beforeEach(() => {
   if (typeof localStorage !== 'undefined') {
     localStorage.clear();