Merge pull request #48 from NiallBunting/main

fix: Allow refreshing of the token when we don't have a user

Author: ahmednfwela

packages/oidc/lib/src/managers/user_manager.dart

@@ -617,16 +617,16 @@ class OidcUserManager {
   ///
   /// An [OidcException] will be thrown if the server returns an error.
   Future<OidcUser?> refreshToken({String? overrideRefreshToken}) async {
+    _ensureInit();
+
     if (!discoveryDocument.grantTypesSupportedOrDefault
         .contains(OidcConstants_GrantType.refreshToken)) {
       //Server doesn't support refresh_token grant.
       return null;
     }
-    final user = currentUser;
-    if (user == null) {
-      return null;
-    }
-    final refreshToken = overrideRefreshToken ?? user.token.refreshToken;
+
+    final refreshToken =
+        overrideRefreshToken ?? currentUser?.token.refreshToken;
     if (refreshToken == null) {
       // Can't refresh the access token anyway.
       return null;
@@ -649,7 +649,7 @@ class OidcUserManager {
       token: OidcToken.fromResponse(
         tokenResponse,
         overrideExpiresIn: settings.getExpiresIn?.call(tokenResponse),
-        sessionState: user.token.sessionState,
+        sessionState: currentUser?.token.sessionState,
       ),
       nonce: null,
       attributes: null,