add failing test for a UI bug: cell disappears after dragging

test/io/github/qualtagh/swing/table/util/MouseRobot.java

@@ -0,0 +1,30 @@
+package io.github.qualtagh.swing.table.util;
+
+import java.awt.AWTException;
+import java.awt.Robot;
+
+public class MouseRobot extends Robot {
+  private int lastX;
+  private int lastY;
+
+  public MouseRobot() throws AWTException {
+    super();
+    initDebugMode();
+  }
+
+  private void initDebugMode() {
+    setAutoDelay( 1000 );
+    setAutoWaitForIdle( true );
+  }
+
+  public void mouseMoveRelative( int x, int y ) {
+    mouseMove( lastX + x, lastY + y );
+  }
+
+  @Override
+  public void mouseMove( int x, int y ) {
+    super.mouseMove( x, y );
+    lastX = x;
+    lastY = y;
+  }
+}

test/io/github/qualtagh/swing/table/view/JBroTableTest.java

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+package io.github.qualtagh.swing.table.view;
+
+import com.sun.java.swing.plaf.windows.WindowsLookAndFeel;
+import io.github.qualtagh.swing.table.model.IModelFieldGroup;
+import io.github.qualtagh.swing.table.model.ModelData;
+import io.github.qualtagh.swing.table.model.ModelField;
+import io.github.qualtagh.swing.table.model.ModelFieldGroup;
+import io.github.qualtagh.swing.table.model.ModelRow;
+import io.github.qualtagh.swing.table.model.ModelSpan;
+import io.github.qualtagh.swing.table.util.MouseRobot;
+import java.awt.FlowLayout;
+import java.awt.Point;
+import java.awt.Rectangle;
+import java.awt.event.InputEvent;
+import java.awt.image.BufferedImage;
+import javax.swing.JFrame;
+import javax.swing.UIManager;
+import static org.junit.Assert.assertFalse;
+import org.junit.Before;
+import org.junit.Test;
+
+public class JBroTableTest {
+  private JBroTable table;
+
+  @Before
+  public void setUp() throws Exception {
+    UIManager.setLookAndFeel( WindowsLookAndFeel.class.getName() );
+    IModelFieldGroup groups[] = new IModelFieldGroup[] {
+      new ModelFieldGroup( "A", "A" )
+        .withChild( new ModelField( "B", "B" ) )
+        .withChild( new ModelField( "C", "C" ).withRowspan( 2 ) ),
+      new ModelFieldGroup( "D", "D" )
+        .withChild( new ModelField( "E", "E" ) )
+        .withChild( new ModelField( "F", "F" ) ),
+      new ModelField( "G", "G" ),
+      new ModelFieldGroup( "H", "H" )
+        .withChild( new ModelFieldGroup( "I", "I" )
+                      .withChild( new ModelField( "J", "J" ) ) )
+        .withChild( new ModelField( "K", "K" ) )
+        .withChild( new ModelFieldGroup( "L", "L" )
+                      .withChild( new ModelField( "M", "M" ) )
+                      .withChild( new ModelField( "N", "N" ) ) )
+    };
+    ModelData data = new ModelData( groups );
+    ModelField fields[] = ModelFieldGroup.getBottomFields( groups );
+    ModelRow rows[] = new ModelRow[ 10 ];
+    for ( int i = 0; i < rows.length; i++ ) {
+      rows[ i ] = new ModelRow( fields.length );
+      for ( int j = 0; j < fields.length; j++ )
+        rows[ i ].setValue( j, j == 1 || j == 2 ? rows[ i ].getValue( 0 ) : i == j ? "sort me" : fields[ j ].getCaption() + i );
+    }
+    data.setRows( rows );
+    table = new JBroTable( data );
+    table.setAutoCreateRowSorter( true );
+    table.setUI( new JBroTableUI().withSpan( new ModelSpan( "B", "B" ).withColumns( "B", "C", "E" ).withDrawAsHeader( true ) )
+                                  .withSpan( new ModelSpan( "G", "G" ).withColumns( "G", "J" ) ) );
+    JFrame frame = new JFrame( "Testing" );
+    frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
+    frame.setLayout( new FlowLayout() );
+    frame.add( table.getScrollPane() );
+    frame.pack();
+    frame.setLocationRelativeTo( null );
+    frame.setVisible( true );
+  }
+
+  @Test( timeout = 10000L )
+  public void disappearingCell() throws Exception {
+    Point start = table.getLocationOnScreen();
+    MouseRobot robot = new MouseRobot();
+    robot.mouseMove( start.x, start.y );
+    robot.mouseMoveRelative( 120, -10 );
+    robot.mousePress( InputEvent.BUTTON1_DOWN_MASK );
+    robot.mouseMoveRelative( 150, 0 );
+    robot.mouseRelease( InputEvent.BUTTON1_DOWN_MASK );
+    robot.mouseMoveRelative( 10, 0 );
+    BufferedImage bi = robot.createScreenCapture( new Rectangle( start.x, start.y - 75, 400, 75 ) );
+    int actual = bi.getRGB( 220, 60 );
+    int wrong = table.getTableHeader().getBackground().getRGB();
+    assertFalse( wrong == actual);
+  }
+}