Add custom argument types for deep-resolved users/members, use these in some places. Deprecate unknownUser (constant) and replace with instances of UnknownUser (class).

src/customArgumentTypes.ts

@@ -0,0 +1,40 @@
+import { convertDelayStringToMS, resolveMember, resolveUser, UnknownUser } from "./utils";
+import { CommandArgumentTypeError } from "knub";
+import { Client, GuildChannel, Message } from "eris";
+
+export const customArgumentTypes = {
+  delay(value) {
+    const result = convertDelayStringToMS(value);
+    if (result == null) {
+      throw new CommandArgumentTypeError(`Could not convert ${value} to a delay`);
+    }
+
+    return result;
+  },
+
+  async resolvedUser(value, msg, bot: Client) {
+    const result = resolveUser(bot, value);
+    if (result == null || result instanceof UnknownUser) {
+      throw new CommandArgumentTypeError(`User \`${value}\` was not found`);
+    }
+    return result;
+  },
+
+  async resolvedUserLoose(value, msg, bot: Client) {
+    const result = resolveUser(bot, value);
+    if (result == null) {
+      throw new CommandArgumentTypeError(`Invalid user: ${value}`);
+    }
+    return result;
+  },
+
+  async resolvedMember(value, msg: Message, bot: Client) {
+    if (!(msg.channel instanceof GuildChannel)) return null;
+
+    const result = await resolveMember(bot, msg.channel.guild, value);
+    if (result == null) {
+      throw new CommandArgumentTypeError(`Member \`${value}\` was not found or they have left the server`);
+    }
+    return result;
+  },
+};