fix: check if localStorage is usable before using it (#558)

[EEX-1349](https://algolia.atlassian.net/browse/EEX-1349)

Fixes #556.

[EEX-1349]:
https://algolia.atlassian.net/browse/EEX-1349?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ

lib/utils/localStorage.ts

@@ -2,7 +2,7 @@
  * A utility class for safely interacting with localStorage.
  */
 export class LocalStorage {
-  static store: Storage | undefined = globalThis.localStorage;
+  static store: Storage | undefined = ensureLocalStorage();
 
   /**
    * Safely get a value from localStorage.
@@ -51,3 +51,14 @@ export class LocalStorage {
     this.store?.removeItem(key);
   }
 }
+
+function ensureLocalStorage(): Storage | undefined {
+  try {
+    const testKey = "__test_localStorage__";
+    globalThis.localStorage.setItem(testKey, testKey);
+    globalThis.localStorage.removeItem(testKey);
+    return globalThis.localStorage;
+  } catch {
+    return undefined;
+  }
+}

package.json

@@ -95,7 +95,7 @@
   "bundlesize": [
     {
       "path": "./dist/search-insights.min.js",
-      "maxSize": "3.60 kB"
+      "maxSize": "3.70 kB"
     }
   ],
   "packageManager": "[email protected]"