fix(console): show each log line once and stop following on user input

runelite-client/src/main/java/net/runelite/client/ui/ClientUI.java

@@ -278,6 +278,7 @@ void removeNavigation(NavigationButton navBtn)
 						: selectedTabHistory.removeLast();
 
 					openPanel(entry.navBtn, entry.sidebarOpen);
+					saveSidebarTab();
 				}
 			}
 			finally
@@ -452,15 +453,7 @@ public void componentMoved(ComponentEvent e)
 
 				if (!updatingNavigation)
 				{
-					sidebarTabRestored = true;
-					if (newSelectedTab == null)
-					{
-						configManager.unsetConfiguration(CONFIG_GROUP, CONFIG_CLIENT_SIDEBAR_TAB);
-					}
-					else
-					{
-						configManager.setConfiguration(CONFIG_GROUP, CONFIG_CLIENT_SIDEBAR_TAB, newSelectedTab.getTooltip());
-					}
+					saveSidebarTab();
 				}
 
 				if (sidebar.isVisible())
@@ -764,6 +757,7 @@ public void show()
 			frame.revalidateMinimumSize();
 			// this must run after the native window border is installed on the window
 			frame.updateContainsInScreen();
+			sidebarTabRestored = true;
 		});
 
 		// Show out of date dialog if needed
@@ -1125,6 +1119,19 @@ public GraphicsConfiguration getGraphicsConfiguration()
 		return frame.getGraphicsConfiguration();
 	}
 
+	private void saveSidebarTab()
+	{
+		sidebarTabRestored = true;
+		if (selectedTab == null)
+		{
+			configManager.unsetConfiguration(CONFIG_GROUP, CONFIG_CLIENT_SIDEBAR_TAB);
+		}
+		else
+		{
+			configManager.setConfiguration(CONFIG_GROUP, CONFIG_CLIENT_SIDEBAR_TAB, selectedTab.getTooltip());
+		}
+	}
+
 	void openPanel(NavigationButton navBtn, boolean showSidebar)
 	{
 		if (navBtn != null && !sidebarEntries.contains(navBtn))
@@ -1294,6 +1301,7 @@ private void initializeConsoleLogging()
 		System.setOut(consolePrintStream);
 
 		LoggerContext loggerContext = (LoggerContext) LoggerFactory.getILoggerFactory();
+		ConsoleLogAppender.bindStdoutAppenders(loggerContext, originalOut);
 		consoleLogAppender = new ConsoleLogAppender(consolePanel::append);
 		consoleLogAppender.setContext(loggerContext);
 		consoleLogAppender.start();

runelite-client/src/main/java/net/runelite/client/ui/ConsoleLogAppender.java

@@ -4,9 +4,16 @@
  */
 package net.runelite.client.ui;
 
+import ch.qos.logback.classic.Logger;
+import ch.qos.logback.classic.LoggerContext;
 import ch.qos.logback.classic.PatternLayout;
 import ch.qos.logback.classic.spi.ILoggingEvent;
+import ch.qos.logback.core.Appender;
 import ch.qos.logback.core.AppenderBase;
+import ch.qos.logback.core.ConsoleAppender;
+import ch.qos.logback.core.joran.spi.ConsoleTarget;
+import java.io.OutputStream;
+import java.util.Iterator;
 import java.util.function.Consumer;
 
 final class ConsoleLogAppender extends AppenderBase<ILoggingEvent>
@@ -19,6 +26,23 @@ final class ConsoleLogAppender extends AppenderBase<ILoggingEvent>
 		this.logConsumer = logConsumer;
 	}
 
+	static void bindStdoutAppenders(LoggerContext context, OutputStream stdout)
+	{
+		for (Logger logger : context.getLoggerList())
+		{
+			Iterator<Appender<ILoggingEvent>> appenders = logger.iteratorForAppenders();
+			while (appenders.hasNext())
+			{
+				Appender<ILoggingEvent> appender = appenders.next();
+				if (appender instanceof ConsoleAppender
+					&& ConsoleTarget.SystemOut.getName().equals(((ConsoleAppender<ILoggingEvent>) appender).getTarget()))
+				{
+					((ConsoleAppender<ILoggingEvent>) appender).setOutputStream(stdout);
+				}
+			}
+		}
+	}
+
 	@Override
 	public void start()
 	{

runelite-client/src/main/java/net/runelite/client/ui/LogConsolePanel.java

@@ -6,6 +6,8 @@
 
 import java.awt.*;
 import java.awt.event.HierarchyEvent;
+import java.awt.event.KeyAdapter;
+import java.awt.event.KeyEvent;
 import java.awt.event.MouseAdapter;
 import java.awt.event.MouseEvent;
 import java.awt.event.MouseMotionAdapter;
@@ -45,6 +47,7 @@ final class LogConsolePanel extends JPanel
 	private boolean followTail = true;
 	private boolean snapQueued;
 	private int snapAttempts;
+	private int tailCaretDot = -1;
 
 	LogConsolePanel()
 	{
@@ -61,15 +64,65 @@ final class LogConsolePanel extends JPanel
 		textArea.setForeground(new Color(0, 255, 70));
 		textArea.setBorder(null);
 
-		DefaultCaret caret = (DefaultCaret) textArea.getCaret();
+		DefaultCaret caret = new DefaultCaret()
+		{
+			@Override
+			protected void adjustVisibility(Rectangle nloc)
+			{
+				if (getDot() != tailCaretDot || getMark() != tailCaretDot)
+				{
+					super.adjustVisibility(nloc);
+				}
+			}
+		};
 		caret.setUpdatePolicy(DefaultCaret.NEVER_UPDATE);
+		textArea.setCaret(caret);
 
 		scrollPane.setBorder(null);
 		add(scrollPane, BorderLayout.CENTER);
 
 		// Following is decided by what the user does, never by measuring the view: under a flood the
 		// scroll position trails the document, which reads as "the user scrolled up".
-		scrollPane.addMouseWheelListener(ev -> reconsiderFollowingTail());
+		scrollPane.addMouseWheelListener(ev ->
+		{
+			if (ev.getPreciseWheelRotation() < 0)
+			{
+				followTail = false;
+			}
+			reconsiderFollowingTail();
+		});
+
+		textArea.addKeyListener(new KeyAdapter()
+		{
+			@Override
+			public void keyPressed(KeyEvent ev)
+			{
+				followTail = false;
+				SwingUtilities.invokeLater(LogConsolePanel.this::reconsiderFollowingTail);
+			}
+		});
+		textArea.addMouseListener(new MouseAdapter()
+		{
+			@Override
+			public void mousePressed(MouseEvent ev)
+			{
+				followTail = false;
+			}
+
+			@Override
+			public void mouseReleased(MouseEvent ev)
+			{
+				reconsiderFollowingTail();
+			}
+		});
+		textArea.addMouseMotionListener(new MouseMotionAdapter()
+		{
+			@Override
+			public void mouseDragged(MouseEvent ev)
+			{
+				followTail = false;
+			}
+		});
 
 		JScrollBar vertical = scrollPane.getVerticalScrollBar();
 		vertical.addMouseListener(new MouseAdapter()
@@ -135,7 +188,7 @@ private void queueSnapToBottom()
 	private void snapToBottom()
 	{
 		int end = textArea.getDocument().getLength();
-		textArea.setCaretPosition(end);
+		moveCaretToTail();
 
 		Rectangle2D newestLine;
 		try
@@ -184,11 +237,10 @@ void append(String text)
 		{
 			pending.append(text, 0, text.length());
 
-			int excess = pending.length() - MAX_CHARACTERS_SCROLLED_UP;
-			if (excess > 0)
+			if (pending.length() > 2 * MAX_CHARACTERS_SCROLLED_UP)
 			{
 				// the oldest buffered lines would be trimmed out of the document on arrival anyway
-				pending.delete(0, excess);
+				pending.delete(0, pending.length() - MAX_CHARACTERS_SCROLLED_UP);
 			}
 
 			if (flushScheduled)
@@ -212,7 +264,8 @@ private void flushPending()
 				return;
 			}
 
-			text = pending.toString();
+			int cap = followTail ? MAX_CHARACTERS : MAX_CHARACTERS_SCROLLED_UP;
+			text = pending.substring(Math.max(0, pending.length() - cap));
 			pending.setLength(0);
 		}
 
@@ -252,7 +305,7 @@ private void appendOnEdt(String text)
 			trimIfNecessary(atBottom);
 			if (atBottom)
 			{
-				textArea.setCaretPosition(document.getLength());
+				moveCaretToTail();
 				// NEVER_UPDATE stops the caret dragging the view, so move it ourselves; the attempt
 				// budget is per batch, or a flood that outruns the layout would exhaust it for good.
 				snapAttempts = 0;
@@ -265,12 +318,18 @@ private void appendOnEdt(String text)
 		}
 	}
 
+	private void moveCaretToTail()
+	{
+		tailCaretDot = textArea.getDocument().getLength();
+		textArea.setCaretPosition(tailCaretDot);
+	}
+
 	// Deferred so the user's gesture has reached the scrollbar before it is read.
 	private void reconsiderFollowingTail()
 	{
 		SwingUtilities.invokeLater(() ->
 		{
-			followTail = isScrolledToBottom();
+			followTail = isScrolledToBottom() && textArea.getSelectionStart() == textArea.getSelectionEnd();
 			if (followTail)
 			{
 				snapAttempts = 0;

runelite-client/src/test/java/net/runelite/client/ui/ConsoleLogAppenderTest.java

@@ -0,0 +1,103 @@
+package net.runelite.client.ui;
+
+import ch.qos.logback.classic.Logger;
+import ch.qos.logback.classic.LoggerContext;
+import ch.qos.logback.classic.encoder.PatternLayoutEncoder;
+import ch.qos.logback.classic.spi.ILoggingEvent;
+import ch.qos.logback.core.ConsoleAppender;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.io.PrintStream;
+import java.nio.charset.StandardCharsets;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import static org.junit.Assert.assertEquals;
+
+public class ConsoleLogAppenderTest
+{
+	private PrintStream originalOut;
+	private LoggerContext context;
+
+	@Before
+	public void setUp()
+	{
+		originalOut = System.out;
+		context = new LoggerContext();
+	}
+
+	@After
+	public void tearDown()
+	{
+		System.setOut(originalOut);
+		context.stop();
+	}
+
+	@Test
+	public void logLineReachesTheConsoleOnceAndStdoutOnce()
+	{
+		ByteArrayOutputStream terminal = new ByteArrayOutputStream();
+		ByteArrayOutputStream consolePanel = new ByteArrayOutputStream();
+		StringBuilder console = new StringBuilder();
+
+		Logger root = context.getLogger(Logger.ROOT_LOGGER_NAME);
+		PatternLayoutEncoder encoder = new PatternLayoutEncoder();
+		encoder.setContext(context);
+		encoder.setPattern("%msg%n");
+		encoder.start();
+		ConsoleAppender<ILoggingEvent> stdout = new ConsoleAppender<>();
+		stdout.setContext(context);
+		stdout.setEncoder(encoder);
+		stdout.start();
+		root.addAppender(stdout);
+
+		System.setOut(new PrintStream(new Tee(consolePanel, terminal), true, StandardCharsets.UTF_8));
+
+		ConsoleLogAppender.bindStdoutAppenders(context, terminal);
+		ConsoleLogAppender appender = new ConsoleLogAppender(console::append);
+		appender.setContext(context);
+		appender.start();
+		root.addAppender(appender);
+
+		root.info("flood line");
+		System.out.println("plain print");
+
+		String panel = console + consolePanel.toString(StandardCharsets.UTF_8);
+		assertEquals(1, occurrences(panel, "flood line"));
+		assertEquals(1, occurrences(panel, "plain print"));
+
+		String out = terminal.toString(StandardCharsets.UTF_8);
+		assertEquals(1, occurrences(out, "flood line"));
+		assertEquals(1, occurrences(out, "plain print"));
+	}
+
+	private static int occurrences(String text, String needle)
+	{
+		int count = 0;
+		for (int i = text.indexOf(needle); i >= 0; i = text.indexOf(needle, i + 1))
+		{
+			count++;
+		}
+		return count;
+	}
+
+	private static final class Tee extends OutputStream
+	{
+		private final OutputStream first;
+		private final OutputStream second;
+
+		private Tee(OutputStream first, OutputStream second)
+		{
+			this.first = first;
+			this.second = second;
+		}
+
+		@Override
+		public void write(int b) throws IOException
+		{
+			first.write(b);
+			second.write(b);
+		}
+	}
+}