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Per the deprecation in v2, the run method from commands is officially removed entirely and will not be aliased nor emit a warning when it's present instead of messageRun.
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⚠️ Again, I reiterate. If you want to keep using message based commands and have NOT moved your run method to messageRun, you MUST do it. You will not get any more runtime warnings, nor TypeScript errors. You have been warned.
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Secondly, the messageRun method is no longer abstract. This mostly affects TypeScript users, but to clarify, due to the nature of our implementation, you are no longer forced to implement any of the *Run methods in your code
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⚠️ With that aside, you ought to override at least one of the methods if you expect the command to work. That could be either the messageRun method, the chatInputRun method or the contextMenuRun method.
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For TypeScript users (as well as JavaScript users that have TS checking enabled), the Command class now has 4 type guards: supportsMessageCommands, supportsChatInputCommands, supportsContextMenuCommands and supportsAutocompleteInteractions. These return true if the Command class you're invoking them on supports the respective *Run methods
const command = stores.get('commands').get('example')!;
if (command.supportsMessageCommands()) {
console.log(`We can run message commands in the example command!`);
// We know that this method is defined and present
await command.messageRun(message);
}