SPIGOT-6705: Re-print tab completion "Display all" message in console, when another message is being logged

By: DerFrZocker <derrieple@gmail.com>

paper-server/nms-patches/net/minecraft/server/dedicated/DedicatedServer.patch

@@ -1,6 +1,6 @@
 --- a/net/minecraft/server/dedicated/DedicatedServer.java
 +++ b/net/minecraft/server/dedicated/DedicatedServer.java
-@@ -53,6 +53,16 @@
+@@ -53,6 +53,18 @@
  import net.minecraft.world.level.storage.Convertable;
  import org.slf4j.Logger;
  
@@ -10,6 +10,8 @@
 +import org.apache.logging.log4j.LogManager;
 +import org.apache.logging.log4j.io.IoBuilder;
 +import org.bukkit.command.CommandSender;
++import org.bukkit.craftbukkit.util.TerminalCompletionHandler;
++import org.bukkit.craftbukkit.util.TerminalConsoleWriterThread;
 +import org.bukkit.event.server.ServerCommandEvent;
 +import org.bukkit.event.server.RemoteServerCommandEvent;
 +// CraftBukkit end
@@ -17,7 +19,7 @@
  public class DedicatedServer extends MinecraftServer implements IMinecraftServer {
  
      static final Logger LOGGER = LogUtils.getLogger();
-@@ -61,7 +71,7 @@
+@@ -61,7 +73,7 @@
      private final List<ServerCommand> consoleInput = Collections.synchronizedList(Lists.newArrayList());
      @Nullable
      private RemoteStatusListener queryThreadGs4;
@@ -26,7 +28,7 @@
      @Nullable
      private RemoteControlListener rconThread;
      public DedicatedServerSettings settings;
-@@ -70,10 +80,12 @@
+@@ -70,10 +82,12 @@
      @Nullable
      private final TextFilter textFilterClient;
  
@@ -42,7 +44,7 @@
          this.textFilterClient = TextFilter.createFromConfig(dedicatedserversettings.getProperties().textFilteringConfig);
      }
  
-@@ -81,13 +93,44 @@
+@@ -81,13 +95,44 @@
      public boolean initServer() throws IOException {
          Thread thread = new Thread("Server console handler") {
              public void run() {
@@ -90,7 +92,7 @@
                      }
                  } catch (IOException ioexception) {
                      DedicatedServer.LOGGER.error("Exception handling console input", ioexception);
-@@ -96,6 +139,27 @@
+@@ -96,6 +141,29 @@
              }
          };
  
@@ -109,7 +111,9 @@
 +            }
 +        }
 +
-+        new org.bukkit.craftbukkit.util.TerminalConsoleWriterThread(System.out, this.reader).start();
++        TerminalConsoleWriterThread writerThread = new TerminalConsoleWriterThread(System.out, this.reader);
++        this.reader.setCompletionHandler(new TerminalCompletionHandler(writerThread, this.reader.getCompletionHandler()));
++        writerThread.start();
 +
 +        System.setOut(IoBuilder.forLogger(logger).setLevel(Level.INFO).buildPrintStream());
 +        System.setErr(IoBuilder.forLogger(logger).setLevel(Level.WARN).buildPrintStream());
@@ -118,7 +122,7 @@
          thread.setDaemon(true);
          thread.setUncaughtExceptionHandler(new DefaultUncaughtExceptionHandler(DedicatedServer.LOGGER));
          thread.start();
-@@ -120,7 +184,7 @@
+@@ -120,7 +188,7 @@
          this.setMotd(dedicatedserverproperties.motd);
          super.setPlayerIdleTimeout((Integer) dedicatedserverproperties.playerIdleTimeout.get());
          this.setEnforceWhitelist(dedicatedserverproperties.enforceWhitelist);
@@ -127,7 +131,7 @@
          DedicatedServer.LOGGER.info("Default game type: {}", dedicatedserverproperties.gamemode);
          InetAddress inetaddress = null;
  
-@@ -144,6 +208,12 @@
+@@ -144,6 +212,12 @@
              return false;
          }
  
@@ -140,7 +144,7 @@
          if (!this.usesAuthentication()) {
              DedicatedServer.LOGGER.warn("**** SERVER IS RUNNING IN OFFLINE/INSECURE MODE!");
              DedicatedServer.LOGGER.warn("The server will make no attempt to authenticate usernames. Beware.");
-@@ -158,19 +228,19 @@
+@@ -158,19 +232,19 @@
          if (!NameReferencingFileConverter.serverReadyAfterUserconversion(this)) {
              return false;
          } else {
@@ -163,7 +167,7 @@
              }
  
              if (dedicatedserverproperties.enableQuery) {
-@@ -296,6 +366,7 @@
+@@ -296,6 +370,7 @@
              this.queryThreadGs4.stop();
          }
  
@@ -171,7 +175,7 @@
      }
  
      @Override
-@@ -317,7 +388,15 @@
+@@ -317,7 +392,15 @@
          while (!this.consoleInput.isEmpty()) {
              ServerCommand servercommand = (ServerCommand) this.consoleInput.remove(0);
  
@@ -188,7 +192,7 @@
          }
  
      }
-@@ -544,16 +623,52 @@
+@@ -544,16 +627,52 @@
  
      @Override
      public String getPluginNames() {
@@ -245,7 +249,7 @@
      }
  
      public void storeUsingWhiteList(boolean flag) {
-@@ -604,4 +719,15 @@
+@@ -604,4 +723,15 @@
      public Optional<MinecraftServer.ServerResourcePackInfo> getServerResourcePack() {
          return this.settings.getProperties().serverResourcePackInfo;
      }

paper-server/src/main/java/org/bukkit/craftbukkit/util/TerminalCompletionHandler.java

@@ -0,0 +1,53 @@
+package org.bukkit.craftbukkit.util;
+
+import java.io.IOException;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import jline.console.ConsoleReader;
+import jline.console.completer.CompletionHandler;
+
+/**
+ * SPIGOT-6705: Make sure we print the display line again on tab completion, so that the user does not get stuck on it
+ * e.g. The user needs to press y / n to continue
+ */
+public class TerminalCompletionHandler implements CompletionHandler {
+
+    private final TerminalConsoleWriterThread writerThread;
+    private final CompletionHandler delegate;
+
+    public TerminalCompletionHandler(TerminalConsoleWriterThread writerThread, CompletionHandler delegate) {
+        this.writerThread = writerThread;
+        this.delegate = delegate;
+    }
+
+    @Override
+    public boolean complete(ConsoleReader reader, List<CharSequence> candidates, int position) throws IOException {
+        // First check normal list, so that we do not unnecessarily create a new HashSet if the not distinct list is already lower
+        if (candidates.size() <= reader.getAutoprintThreshold()) {
+            return delegate.complete(reader, candidates, position);
+        }
+
+        Set<CharSequence> distinct = new HashSet<>(candidates);
+        if (distinct.size() <= reader.getAutoprintThreshold()) {
+            return delegate.complete(reader, candidates, position);
+        }
+
+        writerThread.setCompletion(distinct.size());
+
+        // FIXME: Potential concurrency issue, when terminal writer prints the display message before the delegate does it
+        // resulting in two display message being present, until a new message gets logged or the user presses y / n
+        // But the probability of this happening are probably lower than the effort needed to fix this
+        // And seeing the display message at all should be a higher priority than seeing it two times in rare cases.
+        boolean result = delegate.complete(reader, candidates, position);
+
+        writerThread.setCompletion(-1);
+        // draw line to prevent concurrency issue,
+        // where terminal write would print the display message between delegate#complete finished and the completion set back to -1
+        // Resulting in the display message being present even after pressing y / n
+        reader.drawLine();
+        reader.flush();
+
+        return result;
+    }
+}

paper-server/src/main/java/org/bukkit/craftbukkit/util/TerminalConsoleWriterThread.java

@@ -3,16 +3,21 @@ package org.bukkit.craftbukkit.util;
 import com.mojang.logging.LogQueues;
 import java.io.IOException;
 import java.io.OutputStream;
+import java.util.Locale;
+import java.util.ResourceBundle;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import jline.console.ConsoleReader;
+import jline.console.completer.CandidateListCompletionHandler;
 import org.bukkit.craftbukkit.Main;
 import org.fusesource.jansi.Ansi;
 import org.fusesource.jansi.Ansi.Erase;
 
 public class TerminalConsoleWriterThread extends Thread {
+    private final ResourceBundle bundle = ResourceBundle.getBundle(CandidateListCompletionHandler.class.getName(), Locale.getDefault());
     private final ConsoleReader reader;
     private final OutputStream output;
+    private volatile int completion = -1;
 
     public TerminalConsoleWriterThread(OutputStream output, ConsoleReader reader) {
         super("TerminalConsoleWriter");
@@ -45,6 +50,12 @@ public class TerminalConsoleWriterThread extends Thread {
                     } catch (Throwable ex) {
                         reader.getCursorBuffer().clear();
                     }
+
+                    if (completion > -1) {
+                        // SPIGOT-6705: Make sure we print the display line again on tab completion, so that the user does not get stuck on it
+                        reader.print(String.format(bundle.getString("DISPLAY_CANDIDATES"), completion));
+                    }
+
                     reader.flush();
                 } else {
                     output.write(message.getBytes());
@@ -55,4 +66,8 @@ public class TerminalConsoleWriterThread extends Thread {
             }
         }
     }
+
+    void setCompletion(int completion) {
+        this.completion = completion;
+    }
 }