From 8e5004827edfba54bb6f86739b283e2f1c40c73e Mon Sep 17 00:00:00 2001
From: John Dallaway <john@dallaway.org.uk>
Date: Sun, 15 Oct 2023 17:45:14 +0100
Subject: [PATCH] Provide viewer filter for absent C/C++ translation unit files

---
 core/org.eclipse.cdt.ui/plugin.properties     |  3 ++
 core/org.eclipse.cdt.ui/plugin.xml            |  6 ++++
 .../filters/AbsentTranslationUnitFilter.java  | 30 +++++++++++++++++++
 3 files changed, 39 insertions(+)
 create mode 100644 core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/filters/AbsentTranslationUnitFilter.java

diff --git a/core/org.eclipse.cdt.ui/plugin.properties b/core/org.eclipse.cdt.ui/plugin.properties
index cdc61b49b7e..2e208202e37 100644
--- a/core/org.eclipse.cdt.ui/plugin.properties
+++ b/core/org.eclipse.cdt.ui/plugin.properties
@@ -344,6 +344,9 @@ HideObjectFiles.description= Hides Object files
 HideNonCElements.label= Non-C elements
 HideNonCElements.description= Show only C elements
 
+HideAbsentTranslationUnit.label=Absent C/C++ translation unit files
+HideAbsentTranslationUnit.description=Hides absent C/C++ translation unit files (eg source files of pre-built libraries)
+
 HideNonCProjects.label = Non-C projects
 HideNonCProjects.description= Show only C projects
 
diff --git a/core/org.eclipse.cdt.ui/plugin.xml b/core/org.eclipse.cdt.ui/plugin.xml
index a3e9c39b981..dbd37475e31 100644
--- a/core/org.eclipse.cdt.ui/plugin.xml
+++ b/core/org.eclipse.cdt.ui/plugin.xml
@@ -4203,6 +4203,12 @@
           description="%HideNonCElements.description"
           id="org.eclipse.cdt.ui.navigator.filters.NonCElementFilter"
           name="%HideNonCElements.label"/>
+    <commonFilter
+          activeByDefault="true"
+          class="org.eclipse.cdt.internal.ui.filters.AbsentTranslationUnitFilter"
+          description="%HideAbsentTranslationUnit.description"
+          id="org.eclipse.cdt.ui.navigator.filters.AbsentTranslationUnitFilter"
+          name="%HideAbsentTranslationUnit.label"/>
     <commonFilter
           activeByDefault="true"
           class="org.eclipse.cdt.internal.ui.filters.AnonymousStructFilter"
diff --git a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/filters/AbsentTranslationUnitFilter.java b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/filters/AbsentTranslationUnitFilter.java
new file mode 100644
index 00000000000..6c37aec1896
--- /dev/null
+++ b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/filters/AbsentTranslationUnitFilter.java
@@ -0,0 +1,30 @@
+/*******************************************************************************
+ * Copyright (c) 2023 John Dallaway and others.
+ *
+ * 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
+ *
+ * Contributors:
+ *     John Dallaway - initial implementation (#563)
+ *******************************************************************************/
+package org.eclipse.cdt.internal.ui.filters;
+
+import org.eclipse.cdt.core.model.ITranslationUnit;
+import org.eclipse.jface.viewers.Viewer;
+import org.eclipse.jface.viewers.ViewerFilter;
+
+/**
+ * Filters out translation unit source files that are not present locally
+ */
+public class AbsentTranslationUnitFilter extends ViewerFilter {
+
+	@Override
+	public boolean select(Viewer viewer, Object parentElement, Object element) {
+		return !(element instanceof ITranslationUnit tu) || (null != tu.getResource()) || tu.exists();
+	}
+
+}