From f4f6a2db52d663f70f31393740b70e5a2c831f9b Mon Sep 17 00:00:00 2001
From: Sebastian Thomschke <sebthom@users.noreply.github.com>
Date: Thu, 13 Nov 2025 10:47:09 +0100
Subject: [PATCH] feat: display line numbers in debugger stack frame elements

---
 org.eclipse.lsp4e.debug/META-INF/MANIFEST.MF  |  2 +-
 .../lsp4e/debug/debugmodel/DSPStackFrame.java |  5 ++-
 .../DSPDebugModelPresentation.java            | 38 ++++++++++++++++++-
 3 files changed, 41 insertions(+), 4 deletions(-)

diff --git a/org.eclipse.lsp4e.debug/META-INF/MANIFEST.MF b/org.eclipse.lsp4e.debug/META-INF/MANIFEST.MF
index d4fcbe319..b044de654 100644
--- a/org.eclipse.lsp4e.debug/META-INF/MANIFEST.MF
+++ b/org.eclipse.lsp4e.debug/META-INF/MANIFEST.MF
@@ -3,7 +3,7 @@ Bundle-ManifestVersion: 2
 Bundle-Name: Debug Adapter client for Eclipse IDE (Incubation)
 Bundle-SymbolicName: org.eclipse.lsp4e.debug;singleton:=true
 Bundle-Vendor: Eclipse LSP4E
-Bundle-Version: 0.15.16.qualifier
+Bundle-Version: 0.15.17.qualifier
 Bundle-Activator: org.eclipse.lsp4e.debug.DSPPlugin
 Require-Bundle: org.eclipse.ui,
  org.eclipse.core.runtime,
diff --git a/org.eclipse.lsp4e.debug/src/org/eclipse/lsp4e/debug/debugmodel/DSPStackFrame.java b/org.eclipse.lsp4e.debug/src/org/eclipse/lsp4e/debug/debugmodel/DSPStackFrame.java
index 9583ea39a..64127354e 100644
--- a/org.eclipse.lsp4e.debug/src/org/eclipse/lsp4e/debug/debugmodel/DSPStackFrame.java
+++ b/org.eclipse.lsp4e.debug/src/org/eclipse/lsp4e/debug/debugmodel/DSPStackFrame.java
@@ -183,8 +183,9 @@ public int getCharEnd() throws DebugException {
 		return -1;
 	}
 
-	public String getSourceName() {
-		return stackFrame.getSource().getPath();
+	public @Nullable String getSourceName() {
+		final var source = stackFrame.getSource();
+		return source == null ? null : source.getPath();
 	}
 
 	public Integer getFrameId() {
diff --git a/org.eclipse.lsp4e.debug/src/org/eclipse/lsp4e/debug/presentation/DSPDebugModelPresentation.java b/org.eclipse.lsp4e.debug/src/org/eclipse/lsp4e/debug/presentation/DSPDebugModelPresentation.java
index f937e89fe..14a71b667 100644
--- a/org.eclipse.lsp4e.debug/src/org/eclipse/lsp4e/debug/presentation/DSPDebugModelPresentation.java
+++ b/org.eclipse.lsp4e.debug/src/org/eclipse/lsp4e/debug/presentation/DSPDebugModelPresentation.java
@@ -33,6 +33,7 @@
 import org.eclipse.jface.viewers.LabelProvider;
 import org.eclipse.lsp4e.debug.DSPPlugin;
 import org.eclipse.lsp4e.debug.debugmodel.DSPDebugElement;
+import org.eclipse.lsp4e.debug.debugmodel.DSPStackFrame;
 import org.eclipse.lsp4e.debug.debugmodel.DSPThread;
 import org.eclipse.osgi.util.NLS;
 import org.eclipse.swt.SWT;
@@ -58,7 +59,6 @@ public String getText(Object element) {
 		final var label = new StringBuilder();
 		if (element instanceof DSPThread thread) {
 			label.append(NLS.bind("Thread #{0} [{1}]", thread.getId(), thread.getName()));
-
 		}
 
 		if (label.length() != 0) {
@@ -72,6 +72,28 @@ public String getText(Object element) {
 		} else {
 			// Use default TODO should the entire default be copied here?
 			label.append(DebugUIPlugin.getDefaultLabelProvider().getText(element));
+
+			if (element instanceof DSPStackFrame frame) {
+				try {
+					final int line = frame.getLineNumber();
+					if (line > 0) {
+						final String source = frame.getSourceName();
+						if (source != null) {
+							String file = new Path(source).lastSegment();
+							if (file == null) {
+								file = source;
+							}
+							final String suffix = '(' + file + ":" + line + ')'; //$NON-NLS-1$
+							if (!endsWith(label, suffix)) {
+								label.append(' ');
+								label.append(suffix);
+							}
+						}
+					}
+				} catch (final Exception ex) {
+					DSPPlugin.logWarning("Failed to determine stack frame line number", ex);
+				}
+			}
 		}
 		if (element instanceof DSPDebugElement debugElement) {
 			if (debugElement.getErrorMessage() != null) {
@@ -197,6 +219,20 @@ public void computeDetail(IValue value, IValueDetailListener listener) {
 		}
 	}
 
+	private static boolean endsWith(final StringBuilder sb, final String suffix) {
+		final int sbLen = sb.length();
+		final int suffixLen = suffix.length();
+		if (suffixLen > sbLen) {
+			return false;
+		}
+		for (int i = 1; i <= suffixLen; i++) {
+			if (sb.charAt(sbLen - i) != suffix.charAt(suffixLen - i)) {
+				return false;
+			}
+		}
+		return true;
+	}
+
 	public static Display getDisplay() {
 		Display display;
 		display = Display.getCurrent();