From 8af6268e7ba080dd52b91a8d83699b0262552380 Mon Sep 17 00:00:00 2001
From: suneettipirneni <suneettipirneni@icloud.com>
Date: Sun, 17 Oct 2021 16:54:18 -0400
Subject: [PATCH 1/4] feat: add typeguards to webhooks

---
 src/structures/Webhook.js | 16 ++++++++++++++++
 typings/index.d.ts        |  8 +++++---
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/src/structures/Webhook.js b/src/structures/Webhook.js
index 0bffaa1101e1..e193e3980059 100644
--- a/src/structures/Webhook.js
+++ b/src/structures/Webhook.js
@@ -395,6 +395,22 @@ class Webhook {
     return this.client.rest.cdn.Avatar(this.id, this.avatar, format, size);
   }
 
+  /**
+   * Whether or not this webhook is a channel follower webhook.
+   * @returns {boolean}
+   */
+  isChannelFollower() {
+    return this.type === WebhookTypes.Incoming;
+  }
+
+  /**
+   * Whether or not this webhook is an incoming webhook.
+   * @returns {boolean}
+   */
+  isIncoming() {
+    return this.type === WebhookTypes['Channel Follower'];
+  }
+
   static applyToClass(structure, ignore = []) {
     for (const prop of [
       'send',
diff --git a/typings/index.d.ts b/typings/index.d.ts
index fb954f29314e..3f19762eebad 100644
--- a/typings/index.d.ts
+++ b/typings/index.d.ts
@@ -2200,10 +2200,12 @@ export class Webhook extends WebhookMixin() {
   public guildId: Snowflake;
   public name: string;
   public owner: User | APIUser | null;
-  public sourceGuild: Guild | APIPartialGuild | null;
-  public sourceChannel: NewsChannel | APIPartialChannel | null;
-  public token: string | null;
   public type: WebhookType;
+  public isIncoming(): this is this & { token: string };
+  public isChannelFollower(): this is this & {
+    sourceGuild: Guild | APIPartialGuild;
+    sourceChannel: NewsChannel | APIPartialChannel;
+  };
 }
 
 export class WebhookClient extends WebhookMixin(BaseClient) {

From 9705f2414822650f952066c579135920a57c1db9 Mon Sep 17 00:00:00 2001
From: suneettipirneni <suneettipirneni@icloud.com>
Date: Sun, 17 Oct 2021 17:44:39 -0400
Subject: [PATCH 2/4] fix: typeguard logic

---
 src/structures/Webhook.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/structures/Webhook.js b/src/structures/Webhook.js
index e193e3980059..3a6e4c9abf32 100644
--- a/src/structures/Webhook.js
+++ b/src/structures/Webhook.js
@@ -400,7 +400,7 @@ class Webhook {
    * @returns {boolean}
    */
   isChannelFollower() {
-    return this.type === WebhookTypes.Incoming;
+    return this.type === WebhookTypes['Channel Follower'];
   }
 
   /**
@@ -408,7 +408,7 @@ class Webhook {
    * @returns {boolean}
    */
   isIncoming() {
-    return this.type === WebhookTypes['Channel Follower'];
+    return this.type === WebhookTypes.Incoming;
   }
 
   static applyToClass(structure, ignore = []) {

From 473e0e590c23bf755544593283eb77aaef160f16 Mon Sep 17 00:00:00 2001
From: suneettipirneni <suneettipirneni@icloud.com>
Date: Sun, 17 Oct 2021 17:53:04 -0400
Subject: [PATCH 3/4] chore: revert field deletion

---
 typings/index.d.ts | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/typings/index.d.ts b/typings/index.d.ts
index 3f19762eebad..c1702bd7696f 100644
--- a/typings/index.d.ts
+++ b/typings/index.d.ts
@@ -2200,6 +2200,9 @@ export class Webhook extends WebhookMixin() {
   public guildId: Snowflake;
   public name: string;
   public owner: User | APIUser | null;
+  public sourceGuild: Guild | APIPartialGuild | null;
+  public sourceChannel: NewsChannel | APIPartialChannel | null;
+  public token: string | null;
   public type: WebhookType;
   public isIncoming(): this is this & { token: string };
   public isChannelFollower(): this is this & {

From bbddf7d1b5385ccd7006524da2d049cca910ff72 Mon Sep 17 00:00:00 2001
From: suneettipirneni <suneettipirneni@icloud.com>
Date: Sun, 17 Oct 2021 18:06:15 -0400
Subject: [PATCH 4/4] chore: add type tests

---
 typings/tests.ts | 26 ++++++++++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)

diff --git a/typings/tests.ts b/typings/tests.ts
index 03aa9898be78..59e962374e5a 100644
--- a/typings/tests.ts
+++ b/typings/tests.ts
@@ -1,4 +1,10 @@
-import { APIGuildMember, APIInteractionGuildMember, APIMessage } from 'discord-api-types/v9';
+import {
+  APIGuildMember,
+  APIInteractionGuildMember,
+  APIMessage,
+  APIPartialChannel,
+  APIPartialGuild,
+} from 'discord-api-types/v9';
 import {
   ApplicationCommand,
   ApplicationCommandChannelOptionData,
@@ -473,7 +479,7 @@ client.on('messageReactionRemoveAll', async message => {
 // This is to check that stuff is the right type
 declare const assertIsMessage: (m: Promise<Message>) => void;
 
-client.on('messageCreate', message => {
+client.on('messageCreate', async message => {
   const { channel } = message;
   assertIsMessage(channel.send('string'));
   assertIsMessage(channel.send({}));
@@ -568,6 +574,22 @@ client.on('messageCreate', message => {
     },
   });
 
+  const webhook = await message.fetchWebhook();
+
+  if (webhook.isChannelFollower()) {
+    assertType<Guild | APIPartialGuild>(webhook.sourceGuild);
+    assertType<NewsChannel | APIPartialChannel>(webhook.sourceChannel);
+  } else if (webhook.isIncoming()) {
+    assertType<string>(webhook.token);
+  }
+
+  // @ts-expect-error
+  assertType<Guild | APIPartialGuild>(webhook.sourceGuild);
+  // @ts-expect-error
+  assertType<NewsChannel | APIPartialChannel>(webhook.sourceChannel);
+  // @ts-expect-error
+  assertType<string>(webhook.token);
+
   channel.awaitMessageComponent({
     filter: i => {
       assertType<MessageComponentInteraction>(i);