feat: introduce .isLocked() API method

Introduces a new public API method, `.isLocked()`, to the `SecureLocalStorage` class.

This method returns `true` when the store is in master password mode and the session is locked (i.e., the data encryption key is not in memory). Otherwise, it returns `false`.

This provides a convenient way for consumers of the library to check the lock status before attempting operations that require an unlocked session.

Includes a new test suite for the `isLocked` method, covering all relevant scenarios.

Note: One existing test (`deriveKekFromPassword wraps importKey failures`) is failing. This appears to be an issue in the existing test suite and is unrelated to the changes in this commit.

Author: google-labs-jules[bot]

bun.lock

@@ -11,7 +11,7 @@
         "@types/jest": "^30.0.0",
         "@types/node": "^24.5.2",
         "bun-types": "^1.2.22",
-        "fake-indexeddb": "^6.0.1",
+        "fake-indexeddb": "^6.2.2",
         "typescript": "^5.5.4",
       },
     },

dist/cjs/sls.browser.min.cjs

@@ -45,7 +45,7 @@ export interface SecureLocalStorageOptions {
  * console.log(dataView.value.mySecret); // "hello world"
  *
  * // Wipe the plaintext from memory
- * dataView.wipe();
+ * dataView.clear();
  * ```
  *
  * @example
@@ -89,6 +89,12 @@ export declare class SecureLocalStorage {
      * @returns `true` if a master password is set, `false` otherwise.
      */
     isUsingMasterPassword(): boolean;
+    /**
+     * Checks if the storage is currently locked.
+     * This is only relevant when in master password mode.
+     * @returns `true` if in master password mode and no dek or session, otherwise `false`.
+     */
+    isLocked(): boolean;
     /**
      * Unlocks the data encryption key (DEK) using the provided master password.
      * This is required to access data when in master password mode.

dist/cjs/sls.browser.min.js.map

@@ -20,7 +20,7 @@ export { SecureLocalStorage } from "./api/SecureLocalStorage";
  *   await sls.setData({ secret: 'This is a secret' });
  *   const data = await sls.getData();
  *   console.log(data.value.secret); // "This is a secret"
- *   data.wipe();
+ *   data.clear(); // clears read data memory
  * }
  *
  * main();

dist/esm/sls.browser.min.js

@@ -54,7 +54,7 @@
     "@types/jest": "^30.0.0",
     "@types/node": "^24.5.2",
     "bun-types": "^1.2.22",
-    "fake-indexeddb": "^6.0.1",
+    "fake-indexeddb": "^6.2.2",
     "typescript": "^5.5.4"
   }
 }