Allow optional parameter in fetchAccessToken

src/mastodon.ts

@@ -130,11 +130,14 @@ export default class Mastodon implements MegalodonInterface {
   // apps/oauth
   // ======================================
   public async fetchAccessToken(
-    client_id: string,
+    client_id: string | null,
     client_secret: string,
     code: string,
-    redirect_uri = NO_REDIRECT
+    redirect_uri: string | null = NO_REDIRECT
   ): Promise<OAuth.TokenData> {
+    if (!client_id) {
+      throw new Error('client_id is required')
+    }
     return this.client
       .post<OAuth.TokenDataFromServer>('/oauth/token', {
         client_id,

src/megalodon.ts

@@ -82,7 +82,7 @@ export interface MegalodonInterface {
    * @param code will be generated by the link of #generateAuthUrl or #registerApp
    * @param redirect_uri must be the same uri as the time when you register your OAuth application
    */
-  fetchAccessToken(client_id: string, client_secret: string, code: string, redirect_uri: string): Promise<OAuth.TokenData>
+  fetchAccessToken(client_id: string | null, client_secret: string, code: string, redirect_uri?: string | null): Promise<OAuth.TokenData>
 
   /**
    * POST /oauth/token

src/misskey.ts

@@ -150,10 +150,10 @@ export default class Misskey implements MegalodonInterface {
    * @param _redirect_uri This parameter is not used in this method.
    */
   public async fetchAccessToken(
-    _client_id: string,
+    _client_id: string | null,
     client_secret: string,
     session_token: string,
-    _redirect_uri: string
+    _redirect_uri?: string | null
   ): Promise<OAuth.TokenData> {
     return MisskeyAPI.Client.post<MisskeyAPI.Entity.UserKey>('/api/auth/session/userkey', {
       appSecret: client_secret,