Add asynchronous tab completion to the paper module

cloud-core/src/main/java/com/intellectualsites/commands/CommandManager.java

@@ -122,7 +122,7 @@ public abstract class CommandManager<C> {
      */
     @Nonnull
     public CompletableFuture<CommandResult<C>> executeCommand(@Nonnull final C commandSender, @Nonnull final String input) {
-        final CommandContext<C> context = this.commandContextFactory.create(commandSender);
+        final CommandContext<C> context = this.commandContextFactory.create(false, commandSender);
         final LinkedList<String> inputQueue = this.tokenize(input);
         try {
             if (this.preprocessContext(context, inputQueue) == State.ACCEPTED) {
@@ -147,7 +147,7 @@ public abstract class CommandManager<C> {
      */
     @Nonnull
     public List<String> suggest(@Nonnull final C commandSender, @Nonnull final String input) {
-        final CommandContext<C> context = this.commandContextFactory.create(commandSender);
+        final CommandContext<C> context = this.commandContextFactory.create(true, commandSender);
         final LinkedList<String> inputQueue = this.tokenize(input);
         if (this.preprocessContext(context, inputQueue) == State.ACCEPTED) {
             return this.commandSuggestionProcessor.apply(new CommandPreprocessingContext<>(context, inputQueue),

cloud-core/src/main/java/com/intellectualsites/commands/arguments/CommandArgument.java

@@ -131,7 +131,7 @@ public class CommandArgument<C, T> implements Comparable<CommandArgument<?, ?>>
 
     private static <C> BiFunction<CommandContext<C>, String, List<String>> buildDefaultSuggestionsProvider(
             @Nonnull final CommandArgument<C, ?> argument) {
-        return (context, s) -> argument.getParser().suggestions(context, s);
+        return new DelegatingSuggestionsProvider<>(argument.getName(), argument.getParser());
     }
 
     /**
@@ -404,8 +404,8 @@ public class CommandArgument<C, T> implements Comparable<CommandArgument<?, ?>>
                 this.parser = (c, i) -> ArgumentParseResult
                         .failure(new UnsupportedOperationException("No parser was specified"));
             }
-            if (suggestionsProvider == null) {
+            if (this.suggestionsProvider == null) {
-                suggestionsProvider = this.parser::suggestions;
+                this.suggestionsProvider = new DelegatingSuggestionsProvider<>(this.name, this.parser);
             }
             return new CommandArgument<>(this.required, this.name, this.parser,
                                          this.defaultValue, this.valueType, this.suggestionsProvider);

cloud-core/src/main/java/com/intellectualsites/commands/arguments/DelegatingSuggestionsProvider.java

@@ -0,0 +1,54 @@
+//
+// MIT License
+//
+// Copyright (c) 2020 Alexander Söderberg
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+//
+package com.intellectualsites.commands.arguments;
+
+import com.intellectualsites.commands.arguments.parser.ArgumentParser;
+import com.intellectualsites.commands.context.CommandContext;
+
+import javax.annotation.Nonnull;
+import java.util.List;
+import java.util.function.BiFunction;
+
+final class DelegatingSuggestionsProvider<C> implements BiFunction<CommandContext<C>, String, List<String>> {
+
+    private final String argumentName;
+    private final ArgumentParser<C, ?> parser;
+
+    DelegatingSuggestionsProvider(@Nonnull final String argumentName, @Nonnull final ArgumentParser<C, ?> parser) {
+        this.argumentName = argumentName;
+        this.parser = parser;
+    }
+
+    @Override
+    public List<String> apply(final CommandContext<C> context, final String s) {
+        return this.parser.suggestions(context, s);
+    }
+
+    @Override
+    public String toString() {
+        return String.format("DelegatingSuggestionsProvider{name='%s',parser='%s'}", this.argumentName,
+                             this.parser.getClass().getCanonicalName());
+    }
+
+}

cloud-core/src/main/java/com/intellectualsites/commands/arguments/standard/StringArgument.java

@@ -215,6 +215,14 @@ public final class StringArgument<C> extends CommandArgument<C, String> {
             }
 
             if (this.stringMode == StringMode.SINGLE) {
+                if (commandContext.isSuggestions()) {
+                    final List<String> suggestions = this.suggestionsProvider.apply(commandContext, inputQueue.peek());
+                    if (!suggestions.isEmpty() && !suggestions.contains(input)) {
+                        return ArgumentParseResult.failure(new IllegalArgumentException(
+                                String.format("'%s' is not one of: %s", input, String.join(", ", suggestions))
+                        ));
+                    }
+                }
                 inputQueue.remove();
                 return ArgumentParseResult.success(input);
             }
@@ -222,7 +230,6 @@ public final class StringArgument<C> extends CommandArgument<C, String> {
             final StringJoiner sj = new StringJoiner(" ");
             final int size = inputQueue.size();
 
-
             boolean started = false;
             boolean finished = false;
 

cloud-core/src/main/java/com/intellectualsites/commands/context/CommandContext.java

@@ -37,6 +37,7 @@ public final class CommandContext<C> {
 
     private final Map<String, Object> internalStorage = new HashMap<>();
     private final C commandSender;
+    private final boolean suggestions;
 
     /**
      * Create a new command context instance
@@ -44,7 +45,18 @@ public final class CommandContext<C> {
      * @param commandSender Sender of the command
      */
     public CommandContext(@Nonnull final C commandSender) {
+        this(false, commandSender);
+    }
+
+    /**
+     * Create a new command context instance
+     *
+     * @param suggestions   Whether or not the context is created for command suggestions
+     * @param commandSender Sender of the command
+     */
+    public CommandContext(final boolean suggestions, @Nonnull final C commandSender) {
         this.commandSender = commandSender;
+        this.suggestions = suggestions;
     }
 
     /**
@@ -57,6 +69,15 @@ public final class CommandContext<C> {
         return this.commandSender;
     }
 
+    /**
+     * Check if this context was created for tab completion purposes
+     *
+     * @return {@code true} if this context is requesting suggestions, else {@code false}
+     */
+    public boolean isSuggestions() {
+        return this.suggestions;
+    }
+
     /**
      * Store a value in the context map
      *

cloud-core/src/main/java/com/intellectualsites/commands/context/CommandContextFactory.java

@@ -35,10 +35,11 @@ public interface CommandContextFactory<C> {
     /**
      * Create a new command context
      *
+     * @param suggestions Whether or not the sender is requesting suggestions
      * @param sender Command sender
      * @return Command context
      */
     @Nonnull
-    CommandContext<C> create(@Nonnull C sender);
+    CommandContext<C> create(boolean suggestions, @Nonnull C sender);
 
 }

cloud-core/src/main/java/com/intellectualsites/commands/context/StandardCommandContextFactory.java

@@ -30,13 +30,14 @@ public final class StandardCommandContextFactory<C> implements CommandContextFac
     /**
      * Construct a new command context
      *
-     * @param sender Command sender
+     * @param suggestions Whether or not the sender is requesting suggestions
+     * @param sender      Command sender
      * @return Created context
      */
     @Nonnull
     @Override
-    public CommandContext<C> create(@Nonnull final C sender) {
+    public CommandContext<C> create(final boolean suggestions, @Nonnull final C sender) {
-        return new CommandContext<>(sender);
+        return new CommandContext<>(suggestions, sender);
     }
 
 }

cloud-core/src/test/java/com/intellectualsites/commands/CommandSuggestionsTest.java

@@ -73,6 +73,9 @@ public class CommandSuggestionsTest {
         final String input2 = "test ";
         final List<String> suggestions2 = manager.suggest(new TestCommandSender(), input2);
         Assertions.assertEquals(Arrays.asList("alt", "comb", "one", "two", "var"), suggestions2);
+        final String input3 = "test a";
+        final List<String> suggestions3 = manager.suggest(new TestCommandSender(), input3);
+        Assertions.assertEquals(Collections.singletonList("alt"), suggestions3);
     }
 
     @Test
@@ -82,7 +85,7 @@ public class CommandSuggestionsTest {
         Assertions.assertTrue(suggestions.isEmpty());
         final String input2 = "test var one";
         final List<String> suggestions2 = manager.suggest(new TestCommandSender(), input2);
-        Assertions.assertTrue(suggestions2.isEmpty());
+        Assertions.assertEquals(Collections.emptyList(), suggestions2);
         final String input3 = "test var one f";
         final List<String> suggestions3 = manager.suggest(new TestCommandSender(), input3);
         Assertions.assertEquals(Collections.singletonList("foo"), suggestions3);

cloud-minecraft/cloud-bukkit-test/src/main/java/com/intellectualsites/commands/BukkitTest.java

@@ -88,6 +88,12 @@ public final class BukkitTest extends JavaPlugin {
                 getLogger().warning("Failed to initialize Brigadier support: " + e.getMessage());
             }
 
+            try {
+                ((PaperCommandManager<CommandSender>) mgr).registerAsynchronousCompletions();
+            } catch (final Throwable e) {
+                getLogger().warning("Failed to register asynchronous command completions: " + e.getMessage());
+            }
+
             final AnnotationParser<CommandSender> annotationParser
                     = new AnnotationParser<>(mgr, CommandSender.class, p ->
                     BukkitCommandMetaBuilder.builder().withDescription(p.get(StandardParameters.DESCRIPTION,
@@ -180,7 +186,8 @@ public final class BukkitTest extends JavaPlugin {
     @CommandMethod(value = "annotation|a <input> [number]", permission = "some.permission.node")
     private void annotatedCommand(@Nonnull final Player player,
                                   @Argument("input") @Completions("one,two,duck") @Nonnull final String input,
-                                  @Argument("number") @Range(min = "10", max = "100") final int number) {
+                                  @Argument(value = "number", defaultValue = "5") @Range(min = "10", max = "100")
+                                      final int number) {
         player.sendMessage(ChatColor.GOLD + "Your input was: " + ChatColor.AQUA + input + ChatColor.GREEN + " (" + number + ")");
     }
 

cloud-minecraft/cloud-bukkit/src/main/java/com/intellectualsites/commands/bukkit/BukkitCommand.java

@@ -37,6 +37,7 @@ import org.bukkit.plugin.Plugin;
 
 import javax.annotation.Nonnull;
 import java.util.List;
+import java.util.concurrent.CompletionException;
 
 final class BukkitCommand<C> extends org.bukkit.command.Command implements PluginIdentifiableCommand {
 
@@ -76,6 +77,10 @@ final class BukkitCommand<C> extends org.bukkit.command.Command implements Plugi
                                     builder.toString())
                     .whenComplete(((commandResult, throwable) -> {
                         if (throwable != null) {
+                            if (throwable instanceof CompletionException) {
+                                throwable = throwable.getCause();
+                            }
+                            final Throwable finalThrowable = throwable;
                             if (throwable instanceof InvalidSyntaxException) {
                                 this.manager.handleException(sender,
                                                              InvalidSyntaxException.class,
@@ -84,7 +89,7 @@ final class BukkitCommand<C> extends org.bukkit.command.Command implements Plugi
                                                                              ChatColor.RED + "Invalid Command Syntax. "
                                                                                      + "Correct command syntax is: "
                                                                                      + ChatColor.GRAY + "/"
-                                                                                     + ((InvalidSyntaxException) throwable)
+                                                                                     + ((InvalidSyntaxException) finalThrowable)
                                                                                      .getCorrectSyntax())
                                 );
                             } else if (throwable instanceof InvalidCommandSenderException) {
@@ -92,7 +97,7 @@ final class BukkitCommand<C> extends org.bukkit.command.Command implements Plugi
                                                              InvalidCommandSenderException.class,
                                                              (InvalidCommandSenderException) throwable, (c, e) ->
                                                                      commandSender.sendMessage(
-                                                                             ChatColor.RED + throwable.getMessage())
+                                                                             ChatColor.RED + finalThrowable.getMessage())
                                 );
                             } else if (throwable instanceof NoPermissionException) {
                                 this.manager.handleException(sender,
@@ -112,7 +117,7 @@ final class BukkitCommand<C> extends org.bukkit.command.Command implements Plugi
                                                              (ArgumentParseException) throwable, (c, e) ->
                                                                      commandSender.sendMessage(
                                                                              ChatColor.RED + "Invalid Command Argument: "
-                                                                                     + ChatColor.GRAY + throwable.getCause()
+                                                                                     + ChatColor.GRAY + finalThrowable.getCause()
                                                                                                                  .getMessage())
                                 );
                             } else {

cloud-minecraft/cloud-bungee/src/main/java/com/intellectualsites/commands/bungee/BungeeCommand.java

@@ -37,6 +37,7 @@ import net.md_5.bungee.api.plugin.Command;
 import net.md_5.bungee.api.plugin.TabExecutor;
 
 import javax.annotation.Nonnull;
+import java.util.concurrent.CompletionException;
 
 public final class BungeeCommand<C> extends Command implements TabExecutor {
 
@@ -73,6 +74,10 @@ public final class BungeeCommand<C> extends Command implements TabExecutor {
                                     builder.toString())
             .whenComplete(((commandResult, throwable) -> {
                              if (throwable != null) {
+                                 if (throwable instanceof CompletionException) {
+                                     throwable = throwable.getCause();
+                                 }
+                                 final Throwable finalThrowable = throwable;
                                  if (throwable instanceof InvalidSyntaxException) {
                                      this.manager.handleException(sender,
                                                                   InvalidSyntaxException.class,
@@ -82,16 +87,17 @@ public final class BungeeCommand<C> extends Command implements TabExecutor {
                                                           .color(ChatColor.RED)
                                                           .append("/")
                                                           .color(ChatColor.GRAY)
-                                                          .append(((InvalidSyntaxException) throwable).getCorrectSyntax())
+                                                          .append(((InvalidSyntaxException) finalThrowable).getCorrectSyntax())
                                                           .color(ChatColor.GRAY)
                                                           .create()
                                           )
                                      );
                                  } else if (throwable instanceof InvalidCommandSenderException) {
+                                     final Throwable finalThrowable1 = throwable;
                                      this.manager.handleException(sender,
                                                                   InvalidCommandSenderException.class,
                                                                   (InvalidCommandSenderException) throwable, (c, e) ->
-                                          commandSender.sendMessage(new ComponentBuilder(throwable.getMessage())
+                                          commandSender.sendMessage(new ComponentBuilder(finalThrowable1.getMessage())
                                                                             .color(ChatColor.RED)
                                                                             .create())
                                      );
@@ -117,7 +123,7 @@ public final class BungeeCommand<C> extends Command implements TabExecutor {
                                                                   (ArgumentParseException) throwable, (c, e) ->
                                           commandSender.sendMessage(new ComponentBuilder("Invalid Command Argument: ")
                                                                             .color(ChatColor.GRAY)
-                                                                            .append(throwable.getCause().getMessage())
+                                                                            .append(finalThrowable.getCause().getMessage())
                                                                             .create())
                                      );
                                  } else {

cloud-minecraft/cloud-paper/src/main/java/com/intellectualsites/commands/paper/AsyncCommandSuggestionsListener.java

@@ -0,0 +1,62 @@
+//
+// MIT License
+//
+// Copyright (c) 2020 Alexander Söderberg
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+//
+package com.intellectualsites.commands.paper;
+
+import com.destroystokyo.paper.event.server.AsyncTabCompleteEvent;
+import org.bukkit.command.CommandSender;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.Listener;
+
+import javax.annotation.Nonnull;
+import java.util.ArrayList;
+import java.util.List;
+
+class AsyncCommandSuggestionsListener<C> implements Listener {
+
+    private static final long CACHE_EXPIRATION_TIME = 30L;
+
+    private final PaperCommandManager<C> paperCommandManager;
+
+    AsyncCommandSuggestionsListener(@Nonnull final PaperCommandManager<C> paperCommandManager) {
+        this.paperCommandManager = paperCommandManager;
+    }
+
+    @EventHandler
+    void onTabCompletion(@Nonnull final AsyncTabCompleteEvent event) throws Exception {
+        if (event.getBuffer().isEmpty() || !event.getBuffer().startsWith("/")) {
+            return;
+        }
+        final String[] arguments = event.getBuffer().substring(1).split(" ");
+        if (paperCommandManager.getCommandTree().getNamedNode(arguments[0]) == null) {
+            return;
+        }
+        final CommandSender sender = event.getSender();
+        final C cloudSender = this.paperCommandManager.getCommandSenderMapper().apply(sender);
+        final List<String> suggestions = new ArrayList<>(this.paperCommandManager.suggest(cloudSender,
+                                                                                          event.getBuffer().substring(1)));
+        event.setCompletions(suggestions);
+        event.setHandled(true);
+    }
+
+}

cloud-minecraft/cloud-paper/src/main/java/com/intellectualsites/commands/paper/PaperCommandManager.java

@@ -82,4 +82,12 @@ public class PaperCommandManager<C> extends BukkitCommandManager<C> {
         }
     }
 
+    /**
+     * Register asynchronous completions. This requires all argument parsers to be thread safe, and it
+     * is up to the caller to guarantee that such is the case
+     */
+    public void registerAsynchronousCompletions() {
+        Bukkit.getServer().getPluginManager().registerEvents(new AsyncCommandSuggestionsListener<>(this), this.getOwningPlugin());
+    }
+
 }

cloud-minecraft/cloud-velocity/src/main/java/com/intellectualsites/commands/velocity/VelocityPluginRegistrationHandler.java

@@ -44,6 +44,7 @@ import javax.annotation.Nonnull;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.concurrent.CompletionException;
 
 final class VelocityPluginRegistrationHandler<C> implements CommandRegistrationHandler {
 
@@ -84,6 +85,10 @@ final class VelocityPluginRegistrationHandler<C> implements CommandRegistrationH
                    final C sender = this.manager.getCommandSenderMapper().apply(source);
                    this.manager.executeCommand(sender, input).whenComplete((result, throwable) -> {
                        if (throwable != null) {
+                           if (throwable instanceof CompletionException) {
+                               throwable = throwable.getCause();
+                           }
+                           final Throwable finalThrowable = throwable;
                            if (throwable instanceof InvalidSyntaxException) {
                                this.manager.handleException(sender,
                                                             InvalidSyntaxException.class,
@@ -96,7 +101,7 @@ final class VelocityPluginRegistrationHandler<C> implements CommandRegistrationH
                                this.manager.handleException(sender,
                                                             InvalidCommandSenderException.class,
                                                             (InvalidCommandSenderException) throwable, (c, e) ->
-                                   source.sendMessage(TextComponent.of(throwable.getMessage()).color(NamedTextColor.RED))
+                                   source.sendMessage(TextComponent.of(finalThrowable.getMessage()).color(NamedTextColor.RED))
                                );
                            } else if (throwable instanceof NoPermissionException) {
                                this.manager.handleException(sender,
@@ -114,8 +119,10 @@ final class VelocityPluginRegistrationHandler<C> implements CommandRegistrationH
                                this.manager.handleException(sender,
                                                             ArgumentParseException.class,
                                                             (ArgumentParseException) throwable, (c, e) ->
-                                   source.sendMessage(TextComponent.builder("Invalid Command Argument: ", NamedTextColor.RED)
+                                   source.sendMessage(TextComponent.builder("Invalid Command Argument: ",
-                                                                   .append(throwable.getCause().getMessage(), NamedTextColor.GRAY)
+                                                                            NamedTextColor.RED)
+                                                                   .append(finalThrowable.getCause().getMessage(),
+                                                                           NamedTextColor.GRAY)
                                                                    .build())
                                );
                            } else {