**Refactor command usage printing into CommandUsageFormatter**

Extracted command usage formatting logic from `CommandContainer` into a dedicated `CommandUsageFormatter` class, improving separation of concerns and maintainability. Updated `CommandManager` initialization and added comprehensive unit tests to validate the formatter's functionality.

src/main/java/me/bobert/netneutrality/core/command/Command.java

@@ -12,7 +12,7 @@ import net.dv8tion.jda.api.interactions.commands.DefaultMemberPermissions;
 
 public interface Command {
     enum Type {
-        SLASH, USER, MESSAGE
+        CHAT, USER, MESSAGE
     }
 
     boolean needAdmin();

src/main/java/me/bobert/netneutrality/core/command/CommandContainer.java

@@ -5,7 +5,6 @@ package me.bobert.netneutrality.core.command;
  * https://discord.gg/qUa6zNFZsd
  */
 
-import net.dv8tion.jda.api.entities.channel.ChannelType;
 import net.dv8tion.jda.api.interactions.commands.build.OptionData;
 import net.dv8tion.jda.api.interactions.commands.build.SlashCommandData;
 import net.dv8tion.jda.api.interactions.commands.build.SubcommandData;
@@ -13,25 +12,47 @@ import net.dv8tion.jda.api.interactions.commands.build.SubcommandGroupData;
 import net.dv8tion.jda.internal.interactions.CommandDataImpl;
 
 import java.util.List;
-import java.util.Set;
-import java.util.StringJoiner;
 
 public class CommandContainer {
     public static final CommandContainer NULL_COMMAND = new CommandContainer(null);
+    private static final CommandUsageFormatter USAGE_FORMATTER = new CommandUsageFormatter();
     private final Command command;
-    private CommandDataImpl commandData;
+    private final CommandDataImpl commandData;
-    private List<OptionData> options;
+    private final List<OptionData> options;
-    private List<SubcommandData> subcommands;
+    private final List<SubcommandData> subcommands;
-    private List<SubcommandGroupData> subcommandGroups;
+    private final List<SubcommandGroupData> subcommandGroups;
 
     public CommandContainer(Command command) {
-        this.command = command;
+        this(command, build(command));
-
-        if (command != null) {
-            CommandOptionsBuilder commandOptionsBuilder = new CommandOptionsBuilder(command.getType(), command);
-            command.registerCommandOptions(commandOptionsBuilder);
-            initContainer(commandOptionsBuilder);
     }
+
+    private CommandContainer(Command command, CommandDataImpl commandData) {
+        this.command = command;
+        this.commandData = commandData;
+
+        if (commandData != null) {
+            this.options = commandData.getOptions();
+            this.subcommands = commandData.getSubcommands();
+            this.subcommandGroups = commandData.getSubcommandGroups();
+        } else {
+            this.options = List.of();
+            this.subcommands = List.of();
+            this.subcommandGroups = List.of();
+        }
+    }
+
+    public static CommandContainer of(Command command) {
+        return new CommandContainer(command);
+    }
+
+    private static CommandDataImpl build(Command command) {
+        if (command == null) {
+            return null;
+        }
+
+        CommandOptionsBuilder builder = new CommandOptionsBuilder(command.getType(), command);
+        command.registerCommandOptions(builder);
+        return builder.build();
     }
 
     public Command getCommand() {
@@ -54,129 +75,11 @@ public class CommandContainer {
         return subcommandGroups;
     }
 
-    private void initContainer(CommandOptionsBuilder builder) {
-        this.commandData = builder.build();
-        this.options = commandData.getOptions();
-        this.subcommands = commandData.getSubcommands();
-        this.subcommandGroups = commandData.getSubcommandGroups();
-    }
-
     public boolean isEmpty() {
         return options.isEmpty() && subcommands.isEmpty() && subcommandGroups.isEmpty();
     }
 
     public String printUsage() {
-        StringBuilder usage = new StringBuilder();
+        return USAGE_FORMATTER.format(this);
-        if (!options.isEmpty()) {
-            usage.append("- Usage: /").append(command.getCommandName());
-            for (OptionData option : options) {
-                usage.append(" <").append(option.getName()).append(">");
-            }
-
-            usage.append(printOptions(options, null, false));
-        }
-
-        if (!subcommands.isEmpty()) {
-            for (SubcommandData subcommand : subcommands) {
-                usage.append("- Usage: /").append(command.getCommandName()).append(" ").append(subcommand.getName());
-
-                for (OptionData option : subcommand.getOptions()) {
-                    usage.append(" <").append(option.getName()).append(">");
-                }
-
-                usage.append(" (").append(subcommand.getDescription()).append(")");
-                usage.append(printOptions(subcommand.getOptions(), null, false));
-
-                usage.append("\n");
-            }
-        }
-
-        if (!subcommandGroups.isEmpty()) {
-            for (SubcommandGroupData subcommandGroup : subcommandGroups) {
-                usage.append("- Subcommand: /").append(command.getCommandName())
-                    .append(" ").append(subcommandGroup.getName())
-                    .append(" (").append(subcommandGroup.getDescription()).append(")")
-                    .append("\n");
-
-                for (SubcommandData subcommand : subcommandGroup.getSubcommands()) {
-                    usage.append("  - Usage: /").append(command.getCommandName())
-                        .append(" ").append(subcommandGroup.getName())
-                        .append(" ").append(subcommand.getName());
-
-                    for (OptionData option : subcommand.getOptions()) {
-                        usage.append(" <").append(option.getName()).append(">");
-                    }
-
-                    usage.append(printOptions(subcommand.getOptions(), subcommand.getDescription(), true));
-
-                    usage.append("\n");
-                }
-            }
-        }
-
-        if (!isEmpty()) {
-            usage.append("\n\n-# *: required argument");
-        }
-
-        return usage.toString();
-    }
-
-    private String printOptions(List<OptionData> options, String description, boolean group) {
-        StringBuilder usage = new StringBuilder();
-
-        if (description != null) {
-            usage.append(" (").append(description).append(")");
-        }
-
-        for (OptionData option : options) {
-            usage.append("\n");
-            if (group) {
-                usage.append("  ");
-            }
-
-            usage.append("  - ");
-            if (option.isRequired()) {
-                usage.append("*");
-            }
-            usage.append(option.getName()).append(": ").append(option.getDescription());
-
-            if (option.getMinValue() != null) {
-                usage.append(" [Min value: ").append(option.getMinValue().longValue()).append("]");
-            }
-
-            if (option.getMaxValue() != null) {
-                usage.append(" [Max value: ").append(option.getMaxValue().longValue()).append("]");
-            }
-
-            if (option.getMinLength() != null) {
-                usage.append(" [Min length: ").append(option.getMinLength().longValue()).append("]");
-            }
-
-            if (option.getMaxLength() != null) {
-                usage.append(" [Max length: ").append(option.getMaxLength().longValue()).append("]");
-            }
-
-            List<net.dv8tion.jda.api.interactions.commands.Command.Choice> choices = option.getChoices();
-            if (!choices.isEmpty()) {
-                StringJoiner joiner = new StringJoiner(", ");
-                for (net.dv8tion.jda.api.interactions.commands.Command.Choice choice : choices) {
-                    joiner.add(choice.getAsString());
-                }
-
-                usage.append(" [Available choices: ").append(joiner).append("]");
-            }
-
-            Set<ChannelType> requiredChannelTypes = option.getChannelTypes();
-            if (!requiredChannelTypes.isEmpty()) {
-                StringJoiner joiner = new StringJoiner(", ");
-                for (ChannelType type : requiredChannelTypes) {
-                    joiner.add(type.name());
-                }
-
-                usage.append(" [Required channel types: ").append(joiner).append("]");
-            }
-        }
-
-        return usage.toString();
     }
 }

src/main/java/me/bobert/netneutrality/core/command/CommandManager.java

@@ -57,7 +57,7 @@ public class CommandManager implements CommandRegistry {
     public void init() {
         logger.info("Loading commands..");
 
-        initCommands();
+        ReflectionHelper.loadCommands(Command.class, context, this::onCommandLoaded);
 
         logger.info("Loaded {} commands!", commands.size());
     }
@@ -84,8 +84,7 @@ public class CommandManager implements CommandRegistry {
         return commands;
     }
 
-    public void initCommands() {
+    void onCommandLoaded(Command command) {
-        Consumer<Command> onLoaded = command -> {
         if (!command.isEnabled()) {
             logger.info("Skipping command {} as it is disabled", command.getClass().getName());
             return;
@@ -96,7 +95,7 @@ public class CommandManager implements CommandRegistry {
             return;
         }
 
-            if (command.getDescription() == null && command.getType() == Command.Type.SLASH) {
+        if (command.getDescription() == null && command.getType() == Command.Type.CHAT) {
             logger.error("Failed to load command {}: Command description is null", command.getClass().getName());
             return;
         }
@@ -105,9 +104,6 @@ public class CommandManager implements CommandRegistry {
         if (!commands.containsKey(command.getCommandName())) {
             commands.put(command.getCommandName(), container);
         }
-        };
-
-        ReflectionHelper.loadCommands(Command.class, context, onLoaded);
     }
 
     @Override

src/main/java/me/bobert/netneutrality/core/command/CommandOptionsBuilder.java

@@ -31,7 +31,7 @@ public class CommandOptionsBuilder implements SlashCommandData {
 
     public CommandOptionsBuilder(Command.Type type, Command command) {
 
-        if (type == Command.Type.SLASH) {
+        if (type == Command.Type.CHAT) {
             commandData = (CommandDataImpl) Commands.slash(command.getCommandName(), command.getDescription());
         }
 

src/main/java/me/bobert/netneutrality/core/command/CommandProcessor.java

@@ -83,7 +83,7 @@ public class CommandProcessor {
             logger.info("Executing command {} on guild {}", command.getCommandName(), context.getGuild() == null ? "PrivateMessage" : context.getGuild().getId());
             configureSentry(command);
 
-            if (command.getType() == Command.Type.SLASH && !usageValidator.validate(context, container)) {
+            if (command.getType() == Command.Type.CHAT && !usageValidator.validate(context, container)) {
                 return;
             }
 

src/main/java/me/bobert/netneutrality/core/command/CommandUsageFormatter.java

@@ -0,0 +1,151 @@
+package me.bobert.netneutrality.core.command;
+/*
+ * Copyright (c) anthorob
+ *
+ * https://discord.gg/qUa6zNFZsd
+ */
+
+import net.dv8tion.jda.api.entities.channel.ChannelType;
+import net.dv8tion.jda.api.interactions.commands.build.OptionData;
+import net.dv8tion.jda.api.interactions.commands.build.SubcommandData;
+import net.dv8tion.jda.api.interactions.commands.build.SubcommandGroupData;
+
+import java.util.List;
+import java.util.Set;
+import java.util.StringJoiner;
+
+final class CommandUsageFormatter {
+    private static final String REQUIRED_LEGEND = "\n\n-# *: required argument";
+
+    String format(CommandContainer container) {
+        if (container.isEmpty()) {
+            return "";
+        }
+
+        String commandName = container.getCommand().getCommandName();
+        StringBuilder usage = new StringBuilder();
+        appendOptions(usage, commandName, container.getOptions());
+        appendSubcommands(usage, commandName, container.getSubcommands());
+        appendGroups(usage, commandName, container.getSubcommandGroups());
+        usage.append(REQUIRED_LEGEND);
+
+        return usage.toString();
+    }
+
+    private void appendOptions(StringBuilder usage, String commandName, List<OptionData> options) {
+        if (options.isEmpty()) {
+            return;
+        }
+
+        usage.append("- Usage: /").append(commandName);
+        appendArgs(usage, options);
+        usage.append(describeOptions(options, null, false));
+    }
+
+    private void appendSubcommands(StringBuilder usage, String commandName, List<SubcommandData> subcommands) {
+        for (SubcommandData subcommand : subcommands) {
+            usage.append("- Usage: /").append(commandName).append(" ").append(subcommand.getName());
+            appendArgs(usage, subcommand.getOptions());
+            usage.append(" (").append(subcommand.getDescription()).append(")");
+            usage.append(describeOptions(subcommand.getOptions(), null, false));
+            usage.append("\n");
+        }
+    }
+
+    private void appendGroups(StringBuilder usage, String commandName, List<SubcommandGroupData> groups) {
+        for (SubcommandGroupData group : groups) {
+            usage.append("- Subcommand: /").append(commandName)
+                .append(" ").append(group.getName())
+                .append(" (").append(group.getDescription()).append(")")
+                .append("\n");
+
+            for (SubcommandData subcommand : group.getSubcommands()) {
+                usage.append("  - Usage: /").append(commandName)
+                    .append(" ").append(group.getName())
+                    .append(" ").append(subcommand.getName());
+                appendArgs(usage, subcommand.getOptions());
+                usage.append(describeOptions(subcommand.getOptions(), subcommand.getDescription(), true));
+                usage.append("\n");
+            }
+        }
+    }
+
+    private void appendArgs(StringBuilder usage, List<OptionData> options) {
+        for (OptionData option : options) {
+            usage.append(" <").append(option.getName()).append(">");
+        }
+    }
+
+    private String describeOptions(List<OptionData> options, String description, boolean group) {
+        StringBuilder usage = new StringBuilder();
+
+        if (description != null) {
+            usage.append(" (").append(description).append(")");
+        }
+
+        for (OptionData option : options) {
+            usage.append("\n");
+            if (group) {
+                usage.append("  ");
+            }
+
+            usage.append("  - ");
+            if (option.isRequired()) {
+                usage.append("*");
+            }
+            usage.append(option.getName()).append(": ").append(option.getDescription());
+
+            appendConstraints(usage, option);
+            appendChoices(usage, option);
+            appendChannelTypes(usage, option);
+        }
+
+        return usage.toString();
+    }
+
+    private void appendConstraints(StringBuilder usage, OptionData option) {
+        if (option.getMinValue() != null) {
+            usage.append(" [Min value: ").append(option.getMinValue().longValue()).append("]");
+        }
+
+        if (option.getMaxValue() != null) {
+            usage.append(" [Max value: ").append(option.getMaxValue().longValue()).append("]");
+        }
+
+        if (option.getMinLength() != null) {
+            usage.append(" [Min length: ").append(option.getMinLength().longValue()).append("]");
+        }
+
+        if (option.getMaxLength() != null) {
+            usage.append(" [Max length: ").append(option.getMaxLength().longValue()).append("]");
+        }
+    }
+
+    private void appendChoices(StringBuilder usage, OptionData option) {
+        List<net.dv8tion.jda.api.interactions.commands.Command.Choice> choices = option.getChoices();
+        if (choices.isEmpty()) {
+            return;
+        }
+
+        StringJoiner joiner = new StringJoiner(", ");
+        for (net.dv8tion.jda.api.interactions.commands.Command.Choice choice : choices) {
+            joiner.add(choice.getAsString());
+        }
+
+        usage.append(" [Available choices: ").append(joiner).append("]");
+    }
+
+    private void appendChannelTypes(StringBuilder usage, OptionData option) {
+        Set<ChannelType> types = option.getChannelTypes();
+        if (types.isEmpty()) {
+            return;
+        }
+
+        StringJoiner joiner = new StringJoiner(", ");
+        for (ChannelType type : types) {
+            joiner.add(type.name());
+        }
+
+        usage.append(" [Required channel types: ").append(joiner).append("]");
+    }
+}

src/main/java/me/bobert/netneutrality/core/command/impl/AbstractCommand.java

@@ -34,7 +34,7 @@ public abstract class AbstractCommand implements Command {
 
     @Override
     public Type getType() {
-        return Type.SLASH;
+        return Type.CHAT;
     }
 
     @Override

src/main/java/me/bobert/netneutrality/core/command/precondition/PermissionPrecondition.java

@@ -13,7 +13,7 @@ public class PermissionPrecondition implements CommandPrecondition {
 
     @Override
     public boolean check(CommandContext context, Command command) {
-        if (command.getType() != Command.Type.SLASH) {
+        if (command.getType() != Command.Type.CHAT) {
             return true;
         }
 

src/test/java/me/bobert/netneutrality/core/command/CommandContainerTest.java

@@ -0,0 +1,254 @@
+package me.bobert.netneutrality.core.command;
+
+/*
+ * Copyright (c) anthorob
+ *
+ * https://discord.gg/qUa6zNFZsd
+ */
+
+import net.dv8tion.jda.api.entities.channel.ChannelType;
+import net.dv8tion.jda.api.interactions.commands.OptionType;
+import net.dv8tion.jda.api.interactions.commands.build.OptionData;
+import net.dv8tion.jda.api.interactions.commands.build.SubcommandData;
+import net.dv8tion.jda.api.interactions.commands.build.SubcommandGroupData;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
+
+import java.util.function.Consumer;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertSame;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.mockito.Mockito.doAnswer;
+import static org.mockito.Mockito.when;
+
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class CommandContainerTest {
+
+    @Mock
+    private Command command;
+
+    @BeforeEach
+    void setup() {
+        when(command.getCommandName()).thenReturn("test");
+        when(command.getDescription()).thenReturn("A test command");
+        when(command.getType()).thenReturn(Command.Type.CHAT);
+    }
+
+    private CommandContainer container(Consumer<CommandOptionsBuilder> registration) {
+        doAnswer(invocation -> {
+            registration.accept(invocation.getArgument(0));
+            return null;
+        }).when(command).registerCommandOptions(org.mockito.ArgumentMatchers.any());
+
+        return new CommandContainer(command);
+    }
+
+    // ===== NULL_COMMAND and construction =====
+
+    @Test
+    void nullCommandShouldHaveNoCommand() {
+        assertNull(CommandContainer.NULL_COMMAND.getCommand());
+    }
+
+    @Test
+    void nullCommandShouldBeEmptyAndPrintNothing() {
+        assertTrue(CommandContainer.NULL_COMMAND.isEmpty());
+        assertEquals("", CommandContainer.NULL_COMMAND.printUsage());
+    }
+
+    @Test
+    void ofShouldBuildTheSameAsTheConstructor() {
+        doAnswer(invocation -> {
+            ((CommandOptionsBuilder) invocation.getArgument(0))
+                .addOptions(new OptionData(OptionType.STRING, "text", "Text"));
+            return null;
+        }).when(command).registerCommandOptions(org.mockito.ArgumentMatchers.any());
+
+        CommandContainer container = CommandContainer.of(command);
+
+        assertSame(command, container.getCommand());
+        assertEquals(1, container.getOptions().size());
+    }
+
+    @Test
+    void shouldExposeTheCommand() {
+        assertSame(command, container(_ -> { }).getCommand());
+    }
+
+    @Test
+    void shouldExposeTheBuiltSlashData() {
+        CommandContainer container = container(_ -> { });
+
+        assertNotNull(container.getSlashCommandData());
+        assertEquals("test", container.getSlashCommandData().getName());
+    }
+
+    @Test
+    void shouldExposeTheRegisteredOptionsSubcommandsAndGroups() {
+        CommandContainer container = container(builder -> {
+            builder.addOptions(new OptionData(OptionType.STRING, "text", "Text"));
+        });
+
+        assertEquals(1, container.getOptions().size());
+        assertTrue(container.getSubcommands().isEmpty());
+        assertTrue(container.getSubcommandGroups().isEmpty());
+    }
+
+    // ===== isEmpty =====
+
+    @Test
+    void shouldBeEmptyWithoutAnyOptions() {
+        assertTrue(container(_ -> { }).isEmpty());
+    }
+
+    @Test
+    void shouldNotBeEmptyWithOptions() {
+        assertFalse(container(builder -> builder.addOptions(new OptionData(OptionType.STRING, "text", "Text"))).isEmpty());
+    }
+
+    @Test
+    void shouldNotBeEmptyWithSubcommands() {
+        assertFalse(container(builder -> builder.addSubcommands(new SubcommandData("add", "Adds"))).isEmpty());
+    }
+
+    @Test
+    void shouldNotBeEmptyWithSubcommandGroups() {
+        CommandContainer container = container(builder -> builder.addSubcommandGroups(
+            new SubcommandGroupData("grp", "Group").addSubcommands(new SubcommandData("add", "Adds"))));
+
+        assertFalse(container.isEmpty());
+    }
+
+    // ===== printUsage =====
+
+    @Test
+    void shouldPrintNothingWithoutOptions() {
+        assertEquals("", container(_ -> { }).printUsage());
+    }
+
+    @Test
+    void shouldPrintPlainOptions() {
+        CommandContainer container = container(builder -> builder.addOptions(
+            new OptionData(OptionType.INTEGER, "amount", "Amount", true),
+            new OptionData(OptionType.STRING, "reason", "Reason")));
+
+        assertEquals("- Usage: /test <amount> <reason>\n"
+            + "  - *amount: Amount\n"
+            + "  - reason: Reason\n\n"
+            + "-# *: required argument", container.printUsage());
+    }
+
+    @Test
+    void shouldPrintMinAndMaxValues() {
+        CommandContainer container = container(builder -> builder.addOptions(
+            new OptionData(OptionType.INTEGER, "amount", "Amount").setMinValue(1).setMaxValue(10)));
+
+        String usage = container.printUsage();
+
+        assertTrue(usage.contains("amount: Amount [Min value: 1] [Max value: 10]"), usage);
+    }
+
+    @Test
+    void shouldPrintMinAndMaxLengths() {
+        CommandContainer container = container(builder -> builder.addOptions(
+            new OptionData(OptionType.STRING, "text", "Text").setMinLength(2).setMaxLength(20)));
+
+        String usage = container.printUsage();
+
+        assertTrue(usage.contains("text: Text [Min length: 2] [Max length: 20]"), usage);
+    }
+
+    @Test
+    void shouldPrintChoices() {
+        CommandContainer container = container(builder -> builder.addOptions(
+            new OptionData(OptionType.STRING, "mode", "Mode").addChoice("One", "one").addChoice("Two", "two")));
+
+        String usage = container.printUsage();
+
+        assertTrue(usage.contains("[Available choices: one, two]"), usage);
+    }
+
+    @Test
+    void shouldPrintRequiredChannelTypes() {
+        CommandContainer container = container(builder -> builder.addOptions(
+            new OptionData(OptionType.CHANNEL, "channel", "Channel").setChannelTypes(ChannelType.TEXT)));
+
+        String usage = container.printUsage();
+
+        assertTrue(usage.contains("[Required channel types: TEXT]"), usage);
+    }
+
+    @Test
+    void shouldPrintSubcommands() {
+        CommandContainer container = container(builder -> builder.addSubcommands(
+            new SubcommandData("add", "Adds").addOptions(new OptionData(OptionType.STRING, "name", "Name", true))));
+
+        String usage = container.printUsage();
+
+        assertTrue(usage.contains("- Usage: /test add <name> (Adds)\n  - *name: Name"), usage);
+        assertTrue(usage.endsWith("-# *: required argument"), usage);
+    }
+
+    @Test
+    void shouldPrintSubcommandGroups() {
+        CommandContainer container = container(builder -> builder.addSubcommandGroups(
+            new SubcommandGroupData("grp", "Group").addSubcommands(
+                new SubcommandData("add", "Adds").addOptions(new OptionData(OptionType.STRING, "name", "Name", true)))));
+
+        String usage = container.printUsage();
+
+        assertTrue(usage.contains("- Subcommand: /test grp (Group)\n"), usage);
+        assertTrue(usage.contains("  - Usage: /test grp add <name> (Adds)\n    - *name: Name"), usage);
+        assertTrue(usage.endsWith("-# *: required argument"), usage);
+    }
+
+    @Test
+    void shouldPrintExactSubcommandUsage() {
+        CommandContainer container = container(builder -> builder.addSubcommands(
+            new SubcommandData("add", "Adds").addOptions(new OptionData(OptionType.STRING, "name", "Name", true))));
+
+        assertEquals("- Usage: /test add <name> (Adds)\n  - *name: Name\n\n\n-# *: required argument",
+            container.printUsage());
+    }
+
+    @Test
+    void shouldPrintExactSubcommandGroupUsage() {
+        CommandContainer container = container(builder -> builder.addSubcommandGroups(
+            new SubcommandGroupData("grp", "Group").addSubcommands(
+                new SubcommandData("add", "Adds").addOptions(new OptionData(OptionType.STRING, "name", "Name", true)))));
+
+        assertEquals("- Subcommand: /test grp (Group)\n"
+            + "  - Usage: /test grp add <name> (Adds)\n"
+            + "    - *name: Name\n\n\n-# *: required argument", container.printUsage());
+    }
+
+    @Test
+    void shouldPrintExactAnnotations() {
+        CommandContainer container = container(builder -> builder.addOptions(
+            new OptionData(OptionType.STRING, "mode", "Mode").setMinLength(1).setMaxLength(5)
+                .addChoice("One", "one").addChoice("Two", "two"),
+            new OptionData(OptionType.INTEGER, "n", "N").setMinValue(1).setMaxValue(9),
+            new OptionData(OptionType.CHANNEL, "ch", "Ch").setChannelTypes(ChannelType.TEXT)));
+
+        assertEquals("- Usage: /test <mode> <n> <ch>\n"
+            + "  - mode: Mode [Min length: 1] [Max length: 5] [Available choices: one, two]\n"
+            + "  - n: N [Min value: 1] [Max value: 9]\n"
+            + "  - ch: Ch [Required channel types: TEXT]\n\n"
+            + "-# *: required argument", container.printUsage());
+    }
+
+    @Test
+    void shouldNotPrintTheRequiredLegendForUsagelessCommands() {
+        assertFalse(container(_ -> { }).printUsage().contains("required argument"));
+    }
+}

src/test/java/me/bobert/netneutrality/core/command/CommandDispatchIntegrationTest.java

@@ -0,0 +1,138 @@
+package me.bobert.netneutrality.core.command;
+
+/*
+ * Copyright (c) anthorob
+ *
+ * https://discord.gg/qUa6zNFZsd
+ */
+
+import me.bobert.netneutrality.core.context.CommandContext;
+import me.bobert.netneutrality.core.tasks.TaskManager;
+import me.bobert.netneutrality.db.service.GuildServiceProvider;
+import me.bobert.netneutrality.core.command.precondition.DisabledCommandPrecondition;
+import me.bobert.netneutrality.utils.UserFunction;
+import net.dv8tion.jda.api.entities.Guild;
+import net.dv8tion.jda.api.entities.Member;
+import net.dv8tion.jda.api.entities.User;
+import net.dv8tion.jda.api.entities.channel.unions.MessageChannelUnion;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
+
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+/**
+ * Dispatches through a real {@link CommandProcessor} with the default preconditions, usage validator and
+ * result handler, so only the Discord entities, the registry and the command itself are mocked.
+ */
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class CommandDispatchIntegrationTest {
+    private static final String COMMAND_NAME = "test";
+
+    @Mock
+    private CommandContext context;
+
+    @Mock
+    private CommandRegistry commands;
+
+    @Mock
+    private TaskManager taskManager;
+
+    @Mock
+    private Command command;
+
+    @Mock
+    private Guild guild;
+
+    @Mock
+    private Member member;
+
+    @Mock
+    private User user;
+
+    @Mock
+    private MessageChannelUnion channel;
+
+    private CommandProcessor processor;
+
+    @BeforeEach
+    void setup() {
+        UserFunction.bind((GuildServiceProvider) null);
+        DisabledCommandPrecondition.bind(null);
+
+        when(command.getCommandName()).thenReturn(COMMAND_NAME);
+        when(command.getDescription()).thenReturn("A test command");
+        when(command.getType()).thenReturn(Command.Type.CHAT);
+        when(command.isEnabled()).thenReturn(true);
+        when(command.canBeExecutedFrom(channel)).thenReturn(true);
+        when(command.canBeExecutedBy(member)).thenReturn(true);
+        when(command.execute(context)).thenReturn(CommandExecutionResult.success("Executed"));
+
+        CommandContainer container = new CommandContainer(command);
+        when(commands.hasCommand(COMMAND_NAME)).thenReturn(true);
+        when(commands.getCommandContainer(COMMAND_NAME)).thenReturn(container);
+
+        when(context.parseCommandName()).thenReturn(COMMAND_NAME);
+        when(context.getFullCommand()).thenReturn(COMMAND_NAME);
+        when(context.getId()).thenReturn("context-id");
+        when(context.getGuild()).thenReturn(guild);
+        when(context.isFromGuild()).thenReturn(true);
+        when(context.getGuildUser()).thenReturn(member);
+        when(context.getDiscordUser()).thenReturn(user);
+        when(context.getChannel()).thenReturn(channel);
+        when(context.isValid()).thenReturn(true);
+        when(guild.getId()).thenReturn("111");
+        when(member.getId()).thenReturn("222");
+        when(user.getId()).thenReturn("222");
+        when(channel.getId()).thenReturn("333");
+
+        processor = new CommandProcessor(context, commands, taskManager);
+    }
+
+    @AfterEach
+    void tearDown() {
+        UserFunction.bind((GuildServiceProvider) null);
+        DisabledCommandPrecondition.bind(null);
+    }
+
+    @Test
+    void shouldBlockANonAdminOnAnAdminCommand() {
+        when(command.needAdmin()).thenReturn(true);
+
+        processor.dispatch();
+
+        verify(context).replyEphemeral("You are not powerful enough, scrub");
+        verify(command, never()).execute(any());
+        verify(context, never()).reply("Executed");
+    }
+
+    @Test
+    void shouldRunAnAllowedCommandToCompletion() {
+        processor.dispatch();
+
+        verify(context).setCommand(command);
+        verify(command).execute(context);
+        verify(context).reply("Executed");
+    }
+
+    @Test
+    void shouldBlockAGuildOnlyCommandInPrivateMessages() {
+        when(command.isGuildOnly()).thenReturn(true);
+        when(context.isFromGuild()).thenReturn(false);
+
+        processor.dispatch();
+
+        verify(context).replyEphemeral("This command is only available in a guild");
+        verify(context).deleteMessage();
+        verify(command, never()).execute(any());
+    }
+}

src/test/java/me/bobert/netneutrality/core/command/CommandManagerTest.java

@@ -0,0 +1,246 @@
+package me.bobert.netneutrality.core.command;
+
+/*
+ * Copyright (c) anthorob
+ *
+ * https://discord.gg/qUa6zNFZsd
+ */
+
+import me.bobert.netneutrality.bootstrap.ApplicationContext;
+import net.dv8tion.jda.api.JDA;
+import net.dv8tion.jda.api.interactions.InteractionContextType;
+import net.dv8tion.jda.api.interactions.commands.DefaultMemberPermissions;
+import net.dv8tion.jda.api.interactions.commands.build.CommandData;
+import net.dv8tion.jda.api.interactions.commands.build.SlashCommandData;
+import net.dv8tion.jda.api.requests.restaction.CommandListUpdateAction;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.ArgumentCaptor;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
+
+import java.util.Collection;
+import java.util.List;
+import java.util.Set;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertSame;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.mockito.Mockito.RETURNS_SELF;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class CommandManagerTest {
+
+    @Mock
+    private ApplicationContext applicationContext;
+
+    @Mock
+    private JDA jda;
+
+    private CommandListUpdateAction updateAction;
+
+    private CommandManager manager;
+
+    @BeforeEach
+    void setup() {
+        manager = new CommandManager(applicationContext);
+
+        updateAction = mock(CommandListUpdateAction.class, RETURNS_SELF);
+        when(jda.updateCommands()).thenReturn(updateAction);
+    }
+
+    private Command command(String name, String description) {
+        Command command = mock(Command.class);
+        when(command.getCommandName()).thenReturn(name);
+        when(command.getDescription()).thenReturn(description);
+        when(command.getType()).thenReturn(Command.Type.CHAT);
+        when(command.isEnabled()).thenReturn(true);
+        when(command.isSlashCommand()).thenReturn(true);
+        when(command.isGuildOnly()).thenReturn(false);
+        when(command.getSlashCommandPermission()).thenReturn(DefaultMemberPermissions.ENABLED);
+        return command;
+    }
+
+    @SuppressWarnings("unchecked")
+    private List<CommandData> registeredCommands() {
+        manager.registerSlashCommands(jda);
+
+        ArgumentCaptor<Collection<CommandData>> captor = ArgumentCaptor.forClass(Collection.class);
+        verify(updateAction).addCommands(captor.capture());
+        verify(updateAction).queue();
+        return List.copyOf(captor.getValue());
+    }
+
+    // ===== Construction =====
+
+    @Test
+    void shouldRequireTheApplicationContext() {
+        assertThrows(NullPointerException.class, () -> new CommandManager(null));
+    }
+
+    @Test
+    void shouldStartAfterTheOtherRegistries() {
+        assertEquals(30, manager.priority());
+    }
+
+    // ===== Loading =====
+
+    @Test
+    void shouldRegisterAnEnabledCommand() {
+        Command ping = command("ping", "Pings");
+
+        manager.onCommandLoaded(ping);
+
+        assertTrue(manager.hasCommand("ping"));
+        assertSame(ping, manager.getCommandContainer("ping").getCommand());
+    }
+
+    @Test
+    void shouldSkipDisabledCommands() {
+        Command ping = command("ping", "Pings");
+        when(ping.isEnabled()).thenReturn(false);
+
+        manager.onCommandLoaded(ping);
+
+        assertFalse(manager.hasCommand("ping"));
+    }
+
+    @Test
+    void shouldSkipCommandsWithoutAName() {
+        manager.onCommandLoaded(command(null, "Pings"));
+
+        assertTrue(manager.getCommands().isEmpty());
+    }
+
+    @Test
+    void shouldSkipChatCommandsWithoutADescription() {
+        manager.onCommandLoaded(command("ping", null));
+
+        assertFalse(manager.hasCommand("ping"));
+    }
+
+    @Test
+    void shouldKeepMessageCommandsWithoutADescription() {
+        Command menu = command("menu", null);
+        when(menu.getType()).thenReturn(Command.Type.MESSAGE);
+
+        manager.onCommandLoaded(menu);
+
+        assertTrue(manager.hasCommand("menu"));
+    }
+
+    @Test
+    void shouldKeepTheFirstCommandWhenNamesAreDuplicated() {
+        Command first = command("ping", "First");
+        Command second = command("ping", "Second");
+
+        manager.onCommandLoaded(first);
+        manager.onCommandLoaded(second);
+
+        assertEquals(1, manager.getCommands().size());
+        assertSame(first, manager.getCommandContainer("ping").getCommand());
+    }
+
+    // ===== Lookups =====
+
+    @Test
+    void shouldNotHaveAnUnknownCommand() {
+        assertFalse(manager.hasCommand("unknown"));
+    }
+
+    @Test
+    void shouldReturnTheNullCommandForAnUnknownName() {
+        assertSame(CommandContainer.NULL_COMMAND, manager.getCommandContainer("unknown"));
+    }
+
+    // ===== Slash command registration =====
+
+    @Test
+    void shouldRegisterEnabledSlashCommands() {
+        manager.onCommandLoaded(command("ping", "Pings"));
+
+        List<CommandData> registered = registeredCommands();
+
+        assertEquals(1, registered.size());
+        assertEquals("ping", registered.getFirst().getName());
+    }
+
+    @Test
+    void shouldRegisterNothingWithoutCommands() {
+        assertTrue(registeredCommands().isEmpty());
+    }
+
+    @Test
+    void shouldNotRegisterCommandsThatAreNotSlashCommands() {
+        Command ping = command("ping", "Pings");
+        manager.onCommandLoaded(ping);
+        when(ping.isSlashCommand()).thenReturn(false);
+
+        assertTrue(registeredCommands().isEmpty());
+    }
+
+    @Test
+    void shouldNotRegisterCommandsDisabledAfterLoading() {
+        Command ping = command("ping", "Pings");
+        manager.onCommandLoaded(ping);
+        when(ping.isEnabled()).thenReturn(false);
+
+        assertTrue(registeredCommands().isEmpty());
+    }
+
+    @Test
+    void shouldRestrictGuildOnlyCommandsToGuilds() {
+        Command ping = command("ping", "Pings");
+        when(ping.isGuildOnly()).thenReturn(true);
+        manager.onCommandLoaded(ping);
+
+        SlashCommandData data = (SlashCommandData) registeredCommands().getFirst();
+
+        assertEquals(Set.of(InteractionContextType.GUILD), data.getContexts());
+    }
+
+    @Test
+    void shouldAllowOtherCommandsInGuildsAndBotDms() {
+        manager.onCommandLoaded(command("ping", "Pings"));
+
+        SlashCommandData data = (SlashCommandData) registeredCommands().getFirst();
+
+        assertEquals(Set.of(InteractionContextType.GUILD, InteractionContextType.BOT_DM), data.getContexts());
+    }
+
+    @Test
+    void shouldApplyTheDefaultPermissionOfTheCommand() {
+        Command ping = command("ping", "Pings");
+        when(ping.getSlashCommandPermission()).thenReturn(DefaultMemberPermissions.DISABLED);
+        manager.onCommandLoaded(ping);
+
+        SlashCommandData data = (SlashCommandData) registeredCommands().getFirst();
+
+        assertEquals(DefaultMemberPermissions.DISABLED, data.getDefaultPermissions());
+    }
+
+    @Test
+    void shouldKeepRegisteringWhenOneCommandFails() {
+        Command broken = command("broken", "Broken");
+        CommandContainer brokenContainer = mock(CommandContainer.class);
+        when(brokenContainer.getCommand()).thenReturn(broken);
+        when(brokenContainer.getSlashCommandData()).thenThrow(new IllegalStateException("boom"));
+        manager.getCommands().put("broken", brokenContainer);
+        manager.onCommandLoaded(command("ping", "Pings"));
+
+        List<CommandData> registered = registeredCommands();
+
+        assertEquals(1, registered.size());
+        assertEquals("ping", registered.getFirst().getName());
+        verify(brokenContainer).getSlashCommandData();
+    }
+}

src/test/java/me/bobert/netneutrality/core/command/CommandOptionsBuilderTest.java

@@ -0,0 +1,105 @@
+package me.bobert.netneutrality.core.command;
+
+/*
+ * Copyright (c) anthorob
+ *
+ * https://discord.gg/qUa6zNFZsd
+ */
+
+import net.dv8tion.jda.api.interactions.commands.OptionType;
+import net.dv8tion.jda.api.interactions.commands.build.OptionData;
+import net.dv8tion.jda.api.interactions.commands.build.SubcommandData;
+import net.dv8tion.jda.api.interactions.commands.build.SubcommandGroupData;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.mockito.Mockito.when;
+
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class CommandOptionsBuilderTest {
+
+    @Mock
+    private Command command;
+
+    @BeforeEach
+    void setup() {
+        when(command.getCommandName()).thenReturn("test");
+        when(command.getDescription()).thenReturn("A test command");
+    }
+
+    @Test
+    void shouldBuildSlashDataForChatCommands() {
+        CommandOptionsBuilder builder = new CommandOptionsBuilder(Command.Type.CHAT, command);
+
+        assertNotNull(builder.build());
+        assertEquals(net.dv8tion.jda.api.interactions.commands.Command.Type.SLASH, builder.getType());
+        assertEquals("test", builder.getName());
+        assertEquals("A test command", builder.getDescription());
+    }
+
+    @Test
+    void shouldBuildUserContextMenuDataForUserCommands() {
+        CommandOptionsBuilder builder = new CommandOptionsBuilder(Command.Type.USER, command);
+
+        assertEquals(net.dv8tion.jda.api.interactions.commands.Command.Type.USER, builder.build().getType());
+        assertEquals("test", builder.build().getName());
+    }
+
+    @Test
+    void shouldBuildMessageContextMenuDataForMessageCommands() {
+        CommandOptionsBuilder builder = new CommandOptionsBuilder(Command.Type.MESSAGE, command);
+
+        assertEquals(net.dv8tion.jda.api.interactions.commands.Command.Type.MESSAGE, builder.build().getType());
+        assertEquals("test", builder.build().getName());
+    }
+
+    @Test
+    void shouldStartWithoutOptions() {
+        CommandOptionsBuilder builder = new CommandOptionsBuilder(Command.Type.CHAT, command);
+
+        assertTrue(builder.getOptions().isEmpty());
+        assertTrue(builder.getSubcommands().isEmpty());
+        assertTrue(builder.getSubcommandGroups().isEmpty());
+    }
+
+    @Test
+    void shouldDelegateAddedOptions() {
+        CommandOptionsBuilder builder = new CommandOptionsBuilder(Command.Type.CHAT, command);
+
+        builder.addOptions(new OptionData(OptionType.STRING, "text", "Some text", true));
+
+        assertEquals(1, builder.build().getOptions().size());
+        assertEquals("text", builder.getOptions().getFirst().getName());
+    }
+
+    @Test
+    void shouldDelegateAddedSubcommandsAndGroups() {
+        CommandOptionsBuilder builder = new CommandOptionsBuilder(Command.Type.CHAT, command);
+
+        builder.addSubcommands(new SubcommandData("add", "Adds"));
+        builder.addSubcommandGroups(new SubcommandGroupData("grp", "Group").addSubcommands(new SubcommandData("sub", "Sub")));
+
+        assertEquals("add", builder.getSubcommands().getFirst().getName());
+        assertEquals("grp", builder.getSubcommandGroups().getFirst().getName());
+    }
+
+    @Test
+    void shouldDelegateSettersToTheBuiltData() {
+        CommandOptionsBuilder builder = new CommandOptionsBuilder(Command.Type.CHAT, command);
+
+        builder.setNSFW(true);
+        builder.setDescription("Changed");
+
+        assertTrue(builder.build().isNSFW());
+        assertEquals("Changed", builder.build().getDescription());
+    }
+}

src/test/java/me/bobert/netneutrality/core/command/CommandProcessorTest.java

@@ -109,7 +109,7 @@ class CommandProcessorTest {
         when(commands.getCommandContainer(COMMAND_NAME)).thenReturn(container);
         when(container.getCommand()).thenReturn(command);
         when(command.getCommandName()).thenReturn(COMMAND_NAME);
-        when(command.getType()).thenReturn(Command.Type.SLASH);
+        when(command.getType()).thenReturn(Command.Type.CHAT);
         when(command.execute(context)).thenReturn(result);
         when(usageValidator.validate(context, container)).thenReturn(true);
     }

src/test/java/me/bobert/netneutrality/core/command/CommandResultHandlerTest.java

@@ -0,0 +1,113 @@
+package me.bobert.netneutrality.core.command;
+
+/*
+ * Copyright (c) anthorob
+ *
+ * https://discord.gg/qUa6zNFZsd
+ */
+
+import me.bobert.netneutrality.core.context.CommandContext;
+import me.bobert.netneutrality.core.tasks.Task;
+import me.bobert.netneutrality.core.tasks.TaskManager;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
+
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyNoInteractions;
+import static org.mockito.Mockito.when;
+
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class CommandResultHandlerTest {
+
+    @Mock
+    private CommandContext context;
+
+    @Mock
+    private TaskManager taskManager;
+
+    @Mock
+    private Task task;
+
+    private final CommandResultHandler handler = new CommandResultHandler();
+
+    @Test
+    void shouldDoNothingForNoAction() {
+        handler.handle(context, CommandExecutionResult.none(), taskManager);
+
+        verify(context, never()).reply(anyString());
+        verifyNoInteractions(taskManager);
+    }
+
+    @Test
+    void shouldInsertTheTaskForATaskResult() {
+        handler.handle(context, CommandExecutionResult.task(task), taskManager);
+
+        verify(taskManager).insert(context, task);
+    }
+
+    @Test
+    void shouldNotReplyForATaskResultWithoutMessage() {
+        handler.handle(context, CommandExecutionResult.task(task), taskManager);
+
+        verify(context, never()).reply(anyString());
+    }
+
+    @Test
+    void shouldReplyForASuccess() {
+        handler.handle(context, CommandExecutionResult.success("Done"), taskManager);
+
+        verify(context).reply("Done");
+        verify(taskManager, never()).insert(any(), any());
+    }
+
+    @Test
+    void shouldReplyForAnInfo() {
+        handler.handle(context, CommandExecutionResult.info("FYI"), taskManager);
+
+        verify(context).reply("FYI");
+    }
+
+    @Test
+    void shouldReplyForAWarning() {
+        handler.handle(context, CommandExecutionResult.warn("Careful"), taskManager);
+
+        verify(context).reply("Careful");
+    }
+
+    @Test
+    void shouldReplyForAnError() {
+        handler.handle(context, CommandExecutionResult.error("Broken", new IllegalStateException("boom")), taskManager);
+
+        verify(context).reply("Broken");
+    }
+
+    @Test
+    void shouldReplyForAnErrorWithoutException() {
+        handler.handle(context, CommandExecutionResult.error("Broken"), taskManager);
+
+        verify(context).reply("Broken");
+    }
+
+    @Test
+    void shouldNotReplyWhenTheMessageIsNull() {
+        handler.handle(context, CommandExecutionResult.success((String) null), taskManager);
+
+        verify(context, never()).reply(anyString());
+    }
+
+    @Test
+    void shouldFailForANullResult() {
+        when(context.getId()).thenReturn("context-id");
+
+        assertThrows(RuntimeException.class, () -> handler.handle(context, null, taskManager));
+    }
+}

src/test/java/me/bobert/netneutrality/core/command/CommandUsageFormatterTest.java

@@ -0,0 +1,47 @@
+package me.bobert.netneutrality.core.command;
+
+/*
+ * Copyright (c) anthorob
+ *
+ * https://discord.gg/qUa6zNFZsd
+ */
+
+import net.dv8tion.jda.api.interactions.commands.OptionType;
+import net.dv8tion.jda.api.interactions.commands.build.OptionData;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.Mockito.doAnswer;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+class CommandUsageFormatterTest {
+
+    private final CommandUsageFormatter formatter = new CommandUsageFormatter();
+
+    private Command command() {
+        Command command = mock(Command.class);
+        when(command.getCommandName()).thenReturn("test");
+        when(command.getDescription()).thenReturn("A test command");
+        when(command.getType()).thenReturn(Command.Type.CHAT);
+        return command;
+    }
+
+    @Test
+    void shouldFormatEmptyContainerAsEmptyString() {
+        assertEquals("", formatter.format(new CommandContainer(command())));
+    }
+
+    @Test
+    void shouldFormatOptionsWithRequiredMarkerAndLegend() {
+        Command command = command();
+        doAnswer(invocation -> {
+            CommandOptionsBuilder builder = invocation.getArgument(0);
+            builder.addOptions(new OptionData(OptionType.STRING, "text", "Text", true));
+            return null;
+        }).when(command).registerCommandOptions(org.mockito.ArgumentMatchers.any());
+
+        assertEquals("- Usage: /test <text>\n  - *text: Text\n\n-# *: required argument",
+            formatter.format(new CommandContainer(command)));
+    }
+}

src/test/java/me/bobert/netneutrality/core/command/precondition/DisabledCommandPreconditionTest.java

@@ -0,0 +1,118 @@
+package me.bobert.netneutrality.core.command.precondition;
+
+/*
+ * Copyright (c) anthorob
+ *
+ * https://discord.gg/qUa6zNFZsd
+ */
+
+import me.bobert.netneutrality.core.command.Command;
+import me.bobert.netneutrality.core.context.CommandContext;
+import me.bobert.netneutrality.db.GSettings;
+import me.bobert.netneutrality.db.service.GuildService;
+import me.bobert.netneutrality.db.service.GuildServiceProvider;
+import me.bobert.netneutrality.db.service.GuildSettingService;
+import net.dv8tion.jda.api.entities.Guild;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class DisabledCommandPreconditionTest {
+
+    @Mock
+    private CommandContext context;
+
+    @Mock
+    private Command command;
+
+    @Mock
+    private Guild guild;
+
+    @Mock
+    private GuildServiceProvider provider;
+
+    @Mock
+    private GuildService guildService;
+
+    @Mock
+    private GuildSettingService settingService;
+
+    private final DisabledCommandPrecondition precondition = new DisabledCommandPrecondition();
+
+    @BeforeEach
+    void setup() {
+        when(context.getGuild()).thenReturn(guild);
+        when(guild.getId()).thenReturn("111");
+        when(command.getCommandName()).thenReturn("ping");
+        when(provider.get("111")).thenReturn(guildService);
+        when(guildService.getGuildSettingService()).thenReturn(settingService);
+        when(settingService.getOrDefault(GSettings.DISABLED_COMMANDS)).thenReturn("");
+
+        DisabledCommandPrecondition.bind(provider);
+    }
+
+    @AfterEach
+    void tearDown() {
+        DisabledCommandPrecondition.bind(null);
+    }
+
+    @Test
+    void shouldPassWhenNoProviderIsBound() {
+        DisabledCommandPrecondition.bind(null);
+
+        assertTrue(precondition.check(context, command));
+    }
+
+    @Test
+    void shouldPassOutsideAGuild() {
+        when(context.getGuild()).thenReturn(null);
+
+        assertTrue(precondition.check(context, command));
+
+        verify(context, never()).replyEphemeral(anyString());
+    }
+
+    @Test
+    void shouldPassWhenNoCommandIsDisabled() {
+        assertTrue(precondition.check(context, command));
+
+        verify(context, never()).replyEphemeral(anyString());
+    }
+
+    @Test
+    void shouldPassWhenAnotherCommandIsDisabled() {
+        when(settingService.getOrDefault(GSettings.DISABLED_COMMANDS)).thenReturn("play,skip");
+
+        assertTrue(precondition.check(context, command));
+    }
+
+    @Test
+    void shouldBlockADisabledCommand() {
+        when(settingService.getOrDefault(GSettings.DISABLED_COMMANDS)).thenReturn("play,ping");
+
+        assertFalse(precondition.check(context, command));
+
+        verify(context).replyEphemeral("This command is disabled on this server");
+    }
+
+    @Test
+    void shouldIgnoreCaseAndWhitespaceWhenMatching() {
+        when(settingService.getOrDefault(GSettings.DISABLED_COMMANDS)).thenReturn("play,  PING ");
+
+        assertFalse(precondition.check(context, command));
+    }
+}

src/test/java/me/bobert/netneutrality/core/command/precondition/GuildOnlyPreconditionTest.java

@@ -0,0 +1,68 @@
+package me.bobert.netneutrality.core.command.precondition;
+
+/*
+ * Copyright (c) anthorob
+ *
+ * https://discord.gg/qUa6zNFZsd
+ */
+
+import me.bobert.netneutrality.core.command.Command;
+import me.bobert.netneutrality.core.context.CommandContext;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class GuildOnlyPreconditionTest {
+
+    @Mock
+    private CommandContext context;
+
+    @Mock
+    private Command command;
+
+    private final GuildOnlyPrecondition precondition = new GuildOnlyPrecondition();
+
+    @Test
+    void shouldPassGuildOnlyCommandInAGuild() {
+        when(command.isGuildOnly()).thenReturn(true);
+        when(context.isFromGuild()).thenReturn(true);
+
+        assertTrue(precondition.check(context, command));
+
+        verify(context, never()).replyEphemeral(org.mockito.ArgumentMatchers.anyString());
+        verify(context, never()).deleteMessage();
+    }
+
+    @Test
+    void shouldBlockGuildOnlyCommandOutsideAGuild() {
+        when(command.isGuildOnly()).thenReturn(true);
+        when(context.isFromGuild()).thenReturn(false);
+
+        assertFalse(precondition.check(context, command));
+
+        verify(context).replyEphemeral("This command is only available in a guild");
+        verify(context).deleteMessage();
+    }
+
+    @Test
+    void shouldPassCommandThatIsNotGuildOnlyOutsideAGuild() {
+        when(command.isGuildOnly()).thenReturn(false);
+        when(context.isFromGuild()).thenReturn(false);
+
+        assertTrue(precondition.check(context, command));
+
+        verify(context, never()).replyEphemeral(org.mockito.ArgumentMatchers.anyString());
+        verify(context, never()).deleteMessage();
+    }
+}

src/test/java/me/bobert/netneutrality/core/command/precondition/PermissionPreconditionTest.java

@@ -0,0 +1,142 @@
+package me.bobert.netneutrality.core.command.precondition;
+
+/*
+ * Copyright (c) anthorob
+ *
+ * https://discord.gg/qUa6zNFZsd
+ */
+
+import me.bobert.netneutrality.core.command.Command;
+import me.bobert.netneutrality.core.context.CommandContext;
+import me.bobert.netneutrality.utils.UserFunction;
+import net.dv8tion.jda.api.Permission;
+import net.dv8tion.jda.api.entities.Member;
+import net.dv8tion.jda.api.entities.Role;
+import net.dv8tion.jda.api.entities.channel.unions.MessageChannelUnion;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
+
+import java.util.EnumSet;
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class PermissionPreconditionTest {
+    private static final String DENIED = "You are not powerful enough, scrub";
+
+    @Mock
+    private CommandContext context;
+
+    @Mock
+    private Command command;
+
+    @Mock
+    private Member member;
+
+    @Mock
+    private Role role;
+
+    @Mock
+    private MessageChannelUnion channel;
+
+    private final PermissionPrecondition precondition = new PermissionPrecondition();
+
+    @BeforeEach
+    void setup() {
+        UserFunction.bind(null);
+
+        when(command.getType()).thenReturn(Command.Type.CHAT);
+        when(context.canSkipPermissionCheck()).thenReturn(false);
+        when(context.getChannel()).thenReturn(channel);
+        when(context.getGuildUser()).thenReturn(member);
+        when(command.canBeExecutedFrom(channel)).thenReturn(true);
+        when(command.needAdmin()).thenReturn(false);
+        when(command.canBeExecutedBy(member)).thenReturn(true);
+        when(member.getRoles()).thenReturn(List.of());
+    }
+
+    @AfterEach
+    void tearDown() {
+        UserFunction.bind(null);
+    }
+
+    @Test
+    void shouldSkipTheCheckForMessageCommands() {
+        when(command.getType()).thenReturn(Command.Type.MESSAGE);
+        when(command.canBeExecutedFrom(channel)).thenReturn(false);
+        when(command.canBeExecutedBy(member)).thenReturn(false);
+
+        assertTrue(precondition.check(context, command));
+
+        verify(context, never()).replyEphemeral(anyString());
+    }
+
+    @Test
+    void shouldPassWhenThePermissionCheckCanBeSkipped() {
+        when(context.canSkipPermissionCheck()).thenReturn(true);
+        when(command.canBeExecutedFrom(channel)).thenReturn(false);
+        when(command.canBeExecutedBy(member)).thenReturn(false);
+
+        assertTrue(precondition.check(context, command));
+
+        verify(context, never()).replyEphemeral(anyString());
+    }
+
+    @Test
+    void shouldBlockWhenTheCommandCannotRunInTheChannel() {
+        when(command.canBeExecutedFrom(channel)).thenReturn(false);
+
+        assertFalse(precondition.check(context, command));
+
+        verify(context).replyEphemeral("This command cannot be executed in the current channel");
+    }
+
+    @Test
+    void shouldBlockAnAdminCommandForANonAdmin() {
+        when(command.needAdmin()).thenReturn(true);
+
+        assertFalse(precondition.check(context, command));
+
+        verify(context).replyEphemeral(DENIED);
+    }
+
+    @Test
+    void shouldPassAnAdminCommandForAnAdmin() {
+        when(command.needAdmin()).thenReturn(true);
+        when(role.getPermissions()).thenReturn(EnumSet.of(Permission.ADMINISTRATOR));
+        when(member.getRoles()).thenReturn(List.of(role));
+
+        assertTrue(precondition.check(context, command));
+
+        verify(context, never()).replyEphemeral(anyString());
+    }
+
+    @Test
+    void shouldBlockWhenTheMemberCannotExecuteTheCommand() {
+        when(command.canBeExecutedBy(member)).thenReturn(false);
+
+        assertFalse(precondition.check(context, command));
+
+        verify(context).replyEphemeral(DENIED);
+    }
+
+    @Test
+    void shouldPassWhenEveryCheckSucceeds() {
+        assertTrue(precondition.check(context, command));
+
+        verify(context, never()).replyEphemeral(anyString());
+    }
+}

src/test/java/me/bobert/netneutrality/core/command/precondition/SlashCommandOnlyPreconditionTest.java

@@ -0,0 +1,66 @@
+package me.bobert.netneutrality.core.command.precondition;
+
+/*
+ * Copyright (c) anthorob
+ *
+ * https://discord.gg/qUa6zNFZsd
+ */
+
+import me.bobert.netneutrality.core.command.Command;
+import me.bobert.netneutrality.core.context.CommandContext;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class SlashCommandOnlyPreconditionTest {
+
+    @Mock
+    private CommandContext context;
+
+    @Mock
+    private Command command;
+
+    private final SlashCommandOnlyPrecondition precondition = new SlashCommandOnlyPrecondition();
+
+    @Test
+    void shouldPassSlashOnlyCommandFromAnInteraction() {
+        when(command.isSlashCommandOnly()).thenReturn(true);
+        when(context.isInteraction()).thenReturn(true);
+
+        assertTrue(precondition.check(context, command));
+
+        verify(context, never()).replyEphemeral(anyString());
+    }
+
+    @Test
+    void shouldBlockSlashOnlyCommandSentAsAMessage() {
+        when(command.isSlashCommandOnly()).thenReturn(true);
+        when(context.isInteraction()).thenReturn(false);
+
+        assertFalse(precondition.check(context, command));
+
+        verify(context).replyEphemeral("This command is only available as a slash command");
+    }
+
+    @Test
+    void shouldPassCommandThatIsNotSlashOnlyAsAMessage() {
+        when(command.isSlashCommandOnly()).thenReturn(false);
+        when(context.isInteraction()).thenReturn(false);
+
+        assertTrue(precondition.check(context, command));
+
+        verify(context, never()).replyEphemeral(anyString());
+    }
+}