<commit_before>package seedu.task.logic.commands;

import java.util.EmptyStackException;

import seedu.task.logic.commands.exceptions.CommandException;



public class UndoCommand extends Command {

    public static final String COMMAND_WORD = "undo";

    public static final String MESSAGE_USAGE = COMMAND_WORD + ": Undoes the last mutable action performed. ";


    public static final String MESSAGE_SUCCESS = "Last action undid";
    public static final String MESSAGE_NO_LAST_ACTION = "No previous action has been performed. ";

    @Override
    public CommandResult execute() throws CommandException {
        assert model != null;
        try {
            model.undo();
            return new CommandResult(MESSAGE_SUCCESS);
        } catch (EmptyStackException e) {
            throw new CommandException(MESSAGE_NO_LAST_ACTION);
        }
    }
}<commit_msg>fixed grammar errors<commit_after>package seedu.task.logic.commands;

import java.util.EmptyStackException;

import seedu.task.logic.commands.exceptions.CommandException;



public class UndoCommand extends Command {

    public static final String COMMAND_WORD = "undo";

    public static final String MESSAGE_USAGE = COMMAND_WORD + ": Undoes the last mutable action performed. ";


    public static final String MESSAGE_SUCCESS = "Last action undone. ";
    public static final String MESSAGE_NO_LAST_ACTION = "No previous action has been performed. ";

    @Override
    public CommandResult execute() throws CommandException {
        assert model != null;
        try {
            model.undo();
            return new CommandResult(MESSAGE_SUCCESS);
        } catch (EmptyStackException e) {
            throw new CommandException(MESSAGE_NO_LAST_ACTION);
        }
    }
}
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{'dir': 'git-commits-cleaned', 'id': '3518936', 'n_tokens_mistral': 467, 'n_tokens_neox': 438, 'n_words': 138}