introduce DocumentFooterCodeMining to draw minings at the document end

Author: tobias-melcher

bundles/org.eclipse.jface.text/src/org/eclipse/jface/internal/text/codemining/CodeMiningLineHeaderAnnotation.java

@@ -62,6 +62,12 @@ public class CodeMiningLineHeaderAnnotation extends LineHeaderAnnotation impleme
 	 */
 	private IProgressMonitor fMonitor;
 
+	/**
+	 * Indicates whether the code mining line annotation should be rendered at the very end of the
+	 * document
+	 */
+	private final boolean isDocumentFooterCodeMining;
+
 	/**
 	 * Code mining annotation constructor.
 	 *
@@ -84,10 +90,29 @@ public CodeMiningLineHeaderAnnotation(Position position, ISourceViewer viewer) {
 	 * @param onMouseMove the consumer to be called on mouse move
 	 */
 	public CodeMiningLineHeaderAnnotation(Position position, ISourceViewer viewer, Consumer<MouseEvent> onMouseHover, Consumer<MouseEvent> onMouseOut, Consumer<MouseEvent> onMouseMove) {
+		this(position, viewer, onMouseHover, onMouseOut, onMouseMove, false);
+	}
+
+	/**
+	 * Code mining annotation constructor.
+	 *
+	 * @param position the position
+	 * @param viewer the viewer
+	 * @param onMouseHover the consumer to be called on mouse hover. If set, the implementor needs
+	 *            to take care of setting the cursor if wanted.
+	 * @param onMouseOut the consumer to be called on mouse out. If set, the implementor needs to
+	 *            take care of resetting the cursor.
+	 * @param onMouseMove the consumer to be called on mouse move
+	 * @param isDocumentFooterCodeMining <code>true</code> if the annotation is at the beginning of
+	 *            the last line
+	 */
+	public CodeMiningLineHeaderAnnotation(Position position, ISourceViewer viewer, Consumer<MouseEvent> onMouseHover, Consumer<MouseEvent> onMouseOut, Consumer<MouseEvent> onMouseMove,
+			boolean isDocumentFooterCodeMining) {
 		super(position, viewer, onMouseHover, onMouseOut, onMouseMove);
 		fResolvedMinings= null;
 		fMinings= new ArrayList<>();
 		fBounds= new ArrayList<>();
+		this.isDocumentFooterCodeMining= isDocumentFooterCodeMining;
 	}
 
 	@Override
@@ -282,4 +307,8 @@ public Consumer<MouseEvent> getAction(MouseEvent e) {
 	public boolean isInVisibleLines() {
 		return super.isInVisibleLines();
 	}
+
+	public boolean isDocumentFooterCodeMining() {
+		return isDocumentFooterCodeMining;
+	}
 }

bundles/org.eclipse.jface.text/src/org/eclipse/jface/internal/text/codemining/CodeMiningManager.java

@@ -42,6 +42,7 @@
 import org.eclipse.jface.text.IDocument;
 import org.eclipse.jface.text.ITextViewer;
 import org.eclipse.jface.text.Position;
+import org.eclipse.jface.text.codemining.DocumentFooterCodeMining;
 import org.eclipse.jface.text.codemining.ICodeMining;
 import org.eclipse.jface.text.codemining.ICodeMiningProvider;
 import org.eclipse.jface.text.codemining.LineContentCodeMining;
@@ -273,7 +274,7 @@ private void renderCodeMinings(Map<Position, List<ICodeMining>> groups, ISourceV
 					mouseMove= first.getMouseMove();
 				}
 				ann= inLineHeader
-						? new CodeMiningLineHeaderAnnotation(pos, viewer, mouseHover, mouseOut, mouseMove)
+						? new CodeMiningLineHeaderAnnotation(pos, viewer, mouseHover, mouseOut, mouseMove, first instanceof DocumentFooterCodeMining)
 						: new CodeMiningLineContentAnnotation(pos, viewer, afterPosition, mouseHover, mouseOut, mouseMove);
 			} else if (ann instanceof ICodeMiningAnnotation && ((ICodeMiningAnnotation) ann).isInVisibleLines()) {
 				// annotation is in visible lines

bundles/org.eclipse.jface.text/src/org/eclipse/jface/text/codemining/DocumentFooterCodeMining.java

@@ -0,0 +1,31 @@
+/*******************************************************************************
+* Copyright (c) 2025 SAP SE
+*
+* This program and the accompanying materials
+* are made available under the terms of the Eclipse Public License 2.0
+* which accompanies this distribution, and is available at
+* https://www.eclipse.org/legal/epl-2.0/
+*
+* SPDX-License-Identifier: EPL-2.0
+******************************************************************************/
+package org.eclipse.jface.text.codemining;
+
+import java.util.function.Consumer;
+
+import org.eclipse.swt.events.MouseEvent;
+
+import org.eclipse.jface.text.BadLocationException;
+import org.eclipse.jface.text.IDocument;
+import org.eclipse.jface.text.Position;
+
+/**
+ * A code mining rendered at the start of the line, located at the very end of the document.
+ *
+ * @since 3.27
+ */
+public class DocumentFooterCodeMining extends LineHeaderCodeMining {
+
+	public DocumentFooterCodeMining(IDocument document, ICodeMiningProvider provider, Consumer<MouseEvent> action) throws BadLocationException {
+		super(new Position(document.getLength(), 0), provider, action);
+	}
+}

bundles/org.eclipse.jface.text/src/org/eclipse/jface/text/source/inlined/InlinedAnnotationDrawingStrategy.java

@@ -166,7 +166,11 @@ private static void draw(LineHeaderAnnotation annotation, GC gc, StyledText text
 			// Setting vertical indent first, before computing bounds
 			int height;
 			if (annotation instanceof CodeMiningLineHeaderAnnotation cmlha) {
-				height= cmlha.getHeight(gc);
+				if (cmlha.isDocumentFooterCodeMining()) {
+					height= 0;
+				} else {
+					height= cmlha.getHeight(gc);
+				}
 			} else {
 				height= annotation.getHeight();
 			}
@@ -188,9 +192,24 @@ private static void draw(LineHeaderAnnotation annotation, GC gc, StyledText text
 				x= bounds.x;
 				y= bounds.y;
 			} else {
-				Point locAtOff= textWidget.getLocationAtOffset(offset);
-				x= locAtOff.x;
-				y= locAtOff.y - height;
+				if (annotation instanceof CodeMiningLineHeaderAnnotation cmlha && cmlha.isDocumentFooterCodeMining()) {
+					int lineAtOffset= textWidget.getLineAtOffset(offset);
+					int offsetAtBeginningOfLine= textWidget.getOffsetAtLine(lineAtOffset);
+					if (offsetAtBeginningOfLine >= charCount) {
+						Point locAtOff= textWidget.getLocationAtOffset(offsetAtBeginningOfLine);
+						x= locAtOff.x;
+						y= locAtOff.y;
+					} else {
+						Rectangle bounds= textWidget.getTextBounds(offsetAtBeginningOfLine, offsetAtBeginningOfLine);
+						int lineSpacing= textWidget.getLineSpacing();
+						x= bounds.x;
+						y= bounds.y + bounds.height + lineSpacing;
+					}
+				} else {
+					Point locAtOff= textWidget.getLocationAtOffset(offset);
+					x= locAtOff.x;
+					y= locAtOff.y - height;
+				}
 			}
 			// Draw the line header annotation
 			gc.setBackground(textWidget.getBackground());

tests/org.eclipse.jface.text.tests/src/org/eclipse/jface/text/tests/codemining/CodeMiningTest.java

@@ -52,6 +52,7 @@
 import org.eclipse.jface.text.ITextViewer;
 import org.eclipse.jface.text.Position;
 import org.eclipse.jface.text.codemining.AbstractCodeMiningProvider;
+import org.eclipse.jface.text.codemining.DocumentFooterCodeMining;
 import org.eclipse.jface.text.codemining.ICodeMining;
 import org.eclipse.jface.text.codemining.ICodeMiningProvider;
 import org.eclipse.jface.text.codemining.LineHeaderCodeMining;
@@ -289,6 +290,90 @@ protected boolean condition() {
 		}.waitForCondition(fViewer.getTextWidget().getDisplay(), 10_000));
 	}
 
+	@Test
+	public void testFinalLineCodeMining() throws Exception {
+		String source= "first\nsecond";
+		fViewer.getDocument().set(source);
+		fViewer.setCodeMiningProviders(new ICodeMiningProvider[] { new ICodeMiningProvider() {
+			@Override
+			public CompletableFuture<List<? extends ICodeMining>> provideCodeMinings(ITextViewer viewer, IProgressMonitor monitor) {
+				List<ICodeMining> minings= new ArrayList<>();
+				try {
+					minings.add(new DocumentFooterCodeMining(viewer.getDocument(), this, null) {
+						@Override
+						public String getLabel() {
+							return "multiline first line\nmultiline second line";
+						}
+					});
+				} catch (BadLocationException e) {
+					e.printStackTrace();
+				}
+				return CompletableFuture.completedFuture(minings);
+			}
+
+			@Override
+			public void dispose() {
+			}
+		} });
+		Assert.assertTrue("Code mining is not visible at end of document", new DisplayHelper() {
+			@Override
+			protected boolean condition() {
+				try {
+					boolean res= hasCodeMiningPrintedBelowLine(fViewer, 1);
+					if (!res) {
+						fViewer.getTextWidget().redraw();
+					}
+					return res;
+				} catch (BadLocationException e) {
+					e.printStackTrace();
+					return false;
+				}
+			}
+		}.waitForCondition(fViewer.getTextWidget().getDisplay(), 10_000));
+	}
+
+	@Test
+	public void testFinalLineCodeMiningEmptyDocument() throws Exception {
+		String source= "";
+		fViewer.getDocument().set(source);
+		fViewer.setCodeMiningProviders(new ICodeMiningProvider[] { new ICodeMiningProvider() {
+			@Override
+			public CompletableFuture<List<? extends ICodeMining>> provideCodeMinings(ITextViewer viewer, IProgressMonitor monitor) {
+				List<ICodeMining> minings= new ArrayList<>();
+				try {
+					minings.add(new DocumentFooterCodeMining(viewer.getDocument(), this, null) {
+						@Override
+						public String getLabel() {
+							return "multiline first line\nmultiline second line";
+						}
+					});
+				} catch (BadLocationException e) {
+					e.printStackTrace();
+				}
+				return CompletableFuture.completedFuture(minings);
+			}
+
+			@Override
+			public void dispose() {
+			}
+		} });
+		Assert.assertTrue("Code mining is not visible at end of document", new DisplayHelper() {
+			@Override
+			protected boolean condition() {
+				try {
+					boolean res= hasCodeMiningPrintedBelowLine(fViewer, 0);
+					if (!res) {
+						fViewer.getTextWidget().redraw();
+					}
+					return res;
+				} catch (BadLocationException e) {
+					e.printStackTrace();
+					return false;
+				}
+			}
+		}.waitForCondition(fViewer.getTextWidget().getDisplay(), 10_000));
+	}
+
 	@Test
 	public void testCodeMiningAtEndOfDocumentWithEmptyLine() throws Exception {
 		String source= "first\nsecond\n";
@@ -425,16 +510,27 @@ private static boolean hasCodeMiningPrintedBelowLine(ITextViewer viewer, int lin
 		if (lineLength < 0) {
 			lineLength= 0;
 		}
-		Rectangle lineBounds= widget.getTextBounds(document.getLineOffset(line), document.getLineOffset(line) + lineLength);
-		lineBounds.y= lineBounds.y + lineBounds.height;
+		int lineOffset= document.getLineOffset(line);
+		int startx, starty;
+		if (lineOffset + lineLength >= widget.getCharCount()) {
+			Point loc= widget.getLocationAtOffset(lineOffset);
+			startx= loc.x;
+			starty= loc.y + widget.getLineHeight(lineOffset);
+		} else {
+			Rectangle lineBounds= widget.getTextBounds(lineOffset, lineOffset + lineLength);
+			lineBounds.y= lineBounds.y + lineBounds.height;
+			startx= lineBounds.x;
+			starty= lineBounds.y;
+		}
+
 		Image image= new Image(widget.getDisplay(), widget.getSize().x, widget.getSize().y);
 		try {
 			GC gc= new GC(widget);
 			gc.copyArea(image, 0, 0);
 			gc.dispose();
 			ImageData imageData= image.getImageData();
-			for (int x= lineBounds.x + 1; x < image.getBounds().width && x < imageData.width; x++) {
-				for (int y= lineBounds.y; y < imageData.height - 10 /*do not include the border*/; y++) {
+			for (int x= startx + 1; x < image.getBounds().width && x < imageData.width; x++) {
+				for (int y= starty; y < imageData.height - 10 /*do not include the border*/; y++) {
 					if (!imageData.palette.getRGB(imageData.getPixel(x, y)).equals(widget.getBackground().getRGB())) {
 						// code mining printed
 						return true;