feat: Thoroughly type ContextCommand

src/command.ts

@@ -1,11 +1,15 @@
-import { AutocompleteFocusedOption, AutocompleteInteraction, ChatInputCommandInteraction, ContextMenuCommandBuilder, ContextMenuCommandInteraction, SharedSlashCommand, Snowflake, User } from "discord.js";
+import { ApplicationCommandType, AutocompleteFocusedOption, AutocompleteInteraction, ChatInputCommandInteraction, ContextMenuCommandBuilder, ContextMenuCommandInteraction, Message, SharedSlashCommand, Snowflake, User } from "discord.js";
 import { Config } from "./config";
 
 export abstract class ICommand { }
 
-export abstract class ContextCommand extends ICommand {
+export abstract class ContextCommand<T extends User | Message> extends ICommand {
+    abstract targetType:
+        T extends User ? ApplicationCommandType.User :
+        T extends Message ? ApplicationCommandType.Message :
+        never;
     abstract contextDefinition: ContextMenuCommandBuilder
-    abstract run(interaction: ContextMenuCommandInteraction, target: Snowflake): Promise<void>
+    abstract run(interaction: ContextMenuCommandInteraction, target: T extends User ? User : T extends Message ? Message : never): Promise<void>
 }
 
 export abstract class Command extends ICommand {

src/commands/botsex.ts

@@ -1,13 +1,14 @@
-import { ApplicationCommandType, ContextMenuCommandBuilder, ContextMenuCommandInteraction, InteractionContextType, Snowflake } from "discord.js";
+import { ApplicationCommandType, ContextMenuCommandBuilder, ContextMenuCommandInteraction, InteractionContextType, Snowflake, User } from "discord.js";
 import { ContextCommand } from "../command.ts";
 
-export default class RailUser extends ContextCommand {
+export default class RailUser extends ContextCommand<User> {
+    targetType: ApplicationCommandType.User = ApplicationCommandType.User;
     contextDefinition: ContextMenuCommandBuilder =
         new ContextMenuCommandBuilder()
             .setName('rail')
             .setType(ApplicationCommandType.User)
-    async run(interaction: ContextMenuCommandInteraction, target: Snowflake): Promise<void> {
+    async run(interaction: ContextMenuCommandInteraction, target: User): Promise<void> {
-        await interaction.reply(`Raililng <@${target}>.`)
+        await interaction.reply(`Raililng <@${target.id}>.`)
         await new Promise(resolve => setTimeout(resolve, 1000))
         await interaction.editReply(`UHGhghgghghgh. Railing successfull.`)
     }

src/index.ts

@@ -1,4 +1,6 @@
 import {
+    ApplicationCommand,
+    ApplicationCommandType,
     Client,
     Events,
     GatewayIntentBits,
@@ -43,6 +45,8 @@ const contextCommands = allCommands.filter(it => it instanceof ContextCommand);
 const contextCommandLUT = Object.fromEntries(contextCommands.map(it => [it.contextDefinition.name, it]))
 const commandLookup = Object.fromEntries(commands.map(it => [it.slashCommand.name, it]))
 
+contextCommands.forEach(it => it.contextDefinition.type === it.targetType)
+
 function makeDefaultAvailableEverywhere<T extends { setContexts(...contexts: Array<InteractionContextType>): any, readonly contexts?: InteractionContextType[] }>(t: T): T {
     if (!t.contexts)
         t.setContexts(InteractionContextType.BotDM, InteractionContextType.Guild, InteractionContextType.PrivateChannel)
@@ -69,8 +73,11 @@ client.on(Events.InteractionCreate, async (interaction) => {
         console.error("unknown context command: " + commandName)
         return
     }
+    // The <any> cast here is valid, since the type of the interaction is set in accordance to the definition
+    if (command.targetType != (interaction.isUserContextMenuCommand() ? ApplicationCommandType.User : ApplicationCommandType.Message))
+        console.error("Out of date discord definition of this context command")
     try {
-        await command.run(interaction, interaction.targetId)
+        await command.run(interaction, interaction.isUserContextMenuCommand() ? interaction.targetUser : interaction.targetMessage)
     } catch (e) {
         console.error("error during context command execution: " + commandName, e)
         interaction.reply("something sharted itself")