add channel renderer + try to simplify adapter generics

library/testing.ts

@@ -3,6 +3,7 @@
 import { nanoid } from "nanoid"
 import { raise } from "../helpers/raise"
 import type { Adapter } from "./core/adapters/adapter"
+import type { Channel } from "./internal/channel"
 import type {
   ButtonInteraction,
   CommandInteraction,
@@ -16,9 +17,20 @@ import type {
   MessageSelectOptions,
 } from "./internal/message"
 
-export class TestAdapter implements Adapter<TestCommandInteraction> {
+type TestAdapterGenerics = {
+  commandReplyInit: TestCommandInteraction
+  channelInit: TestChannel
+}
+
+export class TestAdapter implements Adapter<TestAdapterGenerics> {
   messages: TestMessage[] = []
 
+  private constructor() {}
+
+  static create(): Adapter<TestAdapterGenerics> & TestAdapter {
+    return new TestAdapter()
+  }
+
   private componentInteractionListener: (
     interaction: ComponentInteraction,
   ) => void = () => {}
@@ -35,6 +47,10 @@ export class TestAdapter implements Adapter<TestCommandInteraction> {
     return interaction
   }
 
+  createChannel(channel: TestChannel): Channel {
+    return channel
+  }
+
   findButtonByLabel(label: string) {
     for (const message of this.messages) {
       for (const component of message.options.actionRows.flat()) {
@@ -162,3 +178,13 @@ export class TestSelectInteraction implements SelectInteraction {
     this.message.options = options
   }
 }
+
+export class TestChannel implements Channel {
+  constructor(private adapter: TestAdapter) {}
+
+  async send(messageOptions: MessageOptions): Promise<Message> {
+    const message = new TestMessage(messageOptions, this.adapter)
+    this.adapter.messages.push(message)
+    return message
+  }
+}