From 61c06f6e88d2640bd72ca5d7a4a5ed0fe69ffda4 Mon Sep 17 00:00:00 2001
From: Anton Leherbauer <anton.leherbauer@windriver.com>
Date: Tue, 11 Sep 2007 11:38:13 +0000
Subject: [PATCH] Fix for 202085: CDT contributions to ProjectExplorer slows
 performance down dramatically

---
 .../internal/core/model/DeltaProcessor.java   | 10 ++--
 .../cdt/ui/CElementContentProvider.java       | 48 +++++++++++--------
 2 files changed, 34 insertions(+), 24 deletions(-)

diff --git a/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/DeltaProcessor.java b/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/DeltaProcessor.java
index 0b37e21c932..aba3921f727 100644
--- a/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/DeltaProcessor.java
+++ b/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/DeltaProcessor.java
@@ -458,7 +458,11 @@ public class DeltaProcessor {
 			IResource resource = delta.getResource();
 			ICElement current = createElement(resource);
 			updateChildren = updateCurrentDeltaAndIndex(current, delta);
-			if (current == null || current instanceof ISourceRoot) {
+			if (current == null) {
+				nonCResourcesChanged(parent, delta);
+				// no corresponding ICElement - we are done
+				return;
+			} else if (current instanceof ISourceRoot) {
 				nonCResourcesChanged(parent, delta);
 			} else if (current instanceof ICProject) {
 				ICProject cprj = (ICProject)current;
@@ -467,9 +471,7 @@ public class DeltaProcessor {
 					nonCResourcesChanged(parent, delta);
 				}
 			}
-			if (current != null) {
-				parent = current;
-			}
+			parent = current;
 		} catch (CModelException e) {
 		}
 		if (updateChildren){
diff --git a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/ui/CElementContentProvider.java b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/ui/CElementContentProvider.java
index beb30f5257e..77736921c88 100644
--- a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/ui/CElementContentProvider.java
+++ b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/ui/CElementContentProvider.java
@@ -15,23 +15,6 @@ package org.eclipse.cdt.ui;
 
 import java.util.HashSet;
 
-import org.eclipse.cdt.core.model.CModelException;
-import org.eclipse.cdt.core.model.CoreModel;
-import org.eclipse.cdt.core.model.ElementChangedEvent;
-import org.eclipse.cdt.core.model.IArchive;
-import org.eclipse.cdt.core.model.IBinary;
-import org.eclipse.cdt.core.model.ICElement;
-import org.eclipse.cdt.core.model.ICElementDelta;
-import org.eclipse.cdt.core.model.ICProject;
-import org.eclipse.cdt.core.model.IElementChangedListener;
-import org.eclipse.cdt.core.model.IParent;
-import org.eclipse.cdt.core.model.ITranslationUnit;
-import org.eclipse.cdt.core.model.IWorkingCopy;
-import org.eclipse.cdt.internal.core.model.ArchiveContainer;
-import org.eclipse.cdt.internal.core.model.BinaryContainer;
-import org.eclipse.cdt.internal.ui.BaseCElementContentProvider;
-import org.eclipse.cdt.internal.ui.actions.SelectionConverter;
-import org.eclipse.cdt.internal.ui.text.CWordFinder;
 import org.eclipse.core.resources.IResource;
 import org.eclipse.core.resources.IResourceDelta;
 import org.eclipse.jface.text.IRegion;
@@ -45,6 +28,27 @@ import org.eclipse.jface.viewers.Viewer;
 import org.eclipse.swt.widgets.Control;
 import org.eclipse.ui.texteditor.ITextEditor;
 
+import org.eclipse.cdt.core.model.CModelException;
+import org.eclipse.cdt.core.model.CoreModel;
+import org.eclipse.cdt.core.model.ElementChangedEvent;
+import org.eclipse.cdt.core.model.IArchive;
+import org.eclipse.cdt.core.model.IBinary;
+import org.eclipse.cdt.core.model.ICElement;
+import org.eclipse.cdt.core.model.ICElementDelta;
+import org.eclipse.cdt.core.model.ICModel;
+import org.eclipse.cdt.core.model.ICProject;
+import org.eclipse.cdt.core.model.IElementChangedListener;
+import org.eclipse.cdt.core.model.IParent;
+import org.eclipse.cdt.core.model.ITranslationUnit;
+import org.eclipse.cdt.core.model.IWorkingCopy;
+
+import org.eclipse.cdt.internal.core.model.ArchiveContainer;
+import org.eclipse.cdt.internal.core.model.BinaryContainer;
+
+import org.eclipse.cdt.internal.ui.BaseCElementContentProvider;
+import org.eclipse.cdt.internal.ui.actions.SelectionConverter;
+import org.eclipse.cdt.internal.ui.text.CWordFinder;
+
 /**
  * A content provider for C elements.
  * <p>
@@ -169,8 +173,10 @@ public class CElementContentProvider extends BaseCElementContentProvider impleme
 		// well, we do see bugzilla 147694
 		if (element instanceof ITranslationUnit) {
 			ITranslationUnit unit = (ITranslationUnit) element;
-			if (!getProvideWorkingCopy() && unit.isWorkingCopy()) {
-				return;
+			if (unit.isWorkingCopy()) {
+				if (!getProvideWorkingCopy() || kind == ICElementDelta.REMOVED || kind == ICElementDelta.ADDED) {
+					return;
+				}
 			}
 			if (!getProvideMembers() && kind == ICElementDelta.CHANGED) {
 				return;
@@ -230,8 +236,10 @@ public class CElementContentProvider extends BaseCElementContentProvider impleme
 		if (deltas == null)
 			return false;
 		
-		if (deltas.length > 1) {
+		if (deltas.length > 1 && !(parent instanceof ICModel)) {
 			// more than one child changed, refresh from here downwards
+			// but not if the parent is ICModel
+			// see https://bugs.eclipse.org/bugs/show_bug.cgi?id=202085
 			postRefresh(parent);
 			return true;
 		}