From 11c76639db6d78c985fefb2d216b3d57947ab4f5 Mon Sep 17 00:00:00 2001
From: Markus Schorn <markus.schorn@windriver.com>
Date: Mon, 26 Aug 2013 14:25:48 +0200
Subject: [PATCH] Bug 411605: ResourceLookup should honor the
 PathCanonicalization strategy.

---
 .../core/resources/FileRelevance.java         | 37 +++++++++++++++++--
 .../PathCanonicalizationStrategy.java         | 15 ++++++++
 .../core/resources/ResourceLookup.java        |  8 ++--
 3 files changed, 52 insertions(+), 8 deletions(-)

diff --git a/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/resources/FileRelevance.java b/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/resources/FileRelevance.java
index 8a50029e7d1..48c281ee054 100644
--- a/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/resources/FileRelevance.java
+++ b/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/resources/FileRelevance.java
@@ -11,12 +11,15 @@
  *******************************************************************************/
 package org.eclipse.cdt.internal.core.resources;
 
+import java.net.URI;
+
 import org.eclipse.cdt.core.model.CoreModel;
 import org.eclipse.cdt.core.model.ICProject;
 import org.eclipse.cdt.internal.core.model.CModelManager;
 import org.eclipse.core.resources.IFile;
 import org.eclipse.core.resources.IProject;
 import org.eclipse.core.resources.ResourceAttributes;
+import org.eclipse.core.runtime.IPath;
 
 /**
  * This class computes a relevance for files in case we have to select
@@ -43,6 +46,22 @@ public class FileRelevance {
 	 * @return integer representing file relevance. Larger numbers are more relevant
 	 */
 	public static int getRelevance(IFile f, IProject preferredProject) {
+		return getRelevance(f, preferredProject, true, null);
+	}
+
+	/**
+	 * Compute a relevance for the given file. The higher the score the more relevant the
+	 * file. It is determined by the following criteria: <br>
+	 * - file belongs to preferred project <br>
+	 * - file belongs to a cdt-project <br>
+	 * - file belongs to a source folder of a cdt-project <br>
+	 * - file is accessible
+	 * - file is not a link
+	 * - file matches the original location
+	 * @param f the file to compute the relevance for
+	 * @return integer representing file relevance. Larger numbers are more relevant
+	 */
+	public static int getRelevance(IFile f, IProject preferredProject, boolean degradeSymLinks, Object originalLocation) {
 		int result= 0;
 		IProject p= f.getProject();
 		if (p.equals(preferredProject))
@@ -55,14 +74,24 @@ public class FileRelevance {
 				result+= ON_SOURCE_ROOT;
 		}
 
-		if (!f.isAccessible())
+		if (!f.isAccessible()) {
 			result >>= INACCESSIBLE_SHIFT;
-		else {
+		} else if (f.isLinked()) {
+			result -= LINK_PENALTY;
+		} else if (degradeSymLinks) {
 			ResourceAttributes ra = f.getResourceAttributes();
-			if (f.isLinked() || (ra != null && ra.isSymbolicLink()))
+			if (ra != null && ra.isSymbolicLink())
 				result -= LINK_PENALTY;
+		} else {
+			// Symbolic links are not degraded, prefer the original location
+			if (originalLocation instanceof URI) {
+				if (originalLocation.equals(f.getLocationURI()))
+					result += LINK_PENALTY;
+			} else if (originalLocation instanceof IPath) {
+				if (originalLocation.equals(f.getLocation()))
+					result+= LINK_PENALTY;
+			}
 		}
-
 		return result;
 	}
 }
diff --git a/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/resources/PathCanonicalizationStrategy.java b/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/resources/PathCanonicalizationStrategy.java
index e592fb95ab6..5f1fe6ae686 100644
--- a/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/resources/PathCanonicalizationStrategy.java
+++ b/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/resources/PathCanonicalizationStrategy.java
@@ -29,6 +29,10 @@ public abstract class PathCanonicalizationStrategy {
 	public static String getCanonicalPath(File file) {
 		return instance.getCanonicalPathInternal(file);
 	}
+	
+	public static boolean resolvesSymbolicLinks() {
+		return instance.resolvesSymbolicLinksInternal();
+	}
 
 	/**
 	 * Sets path canonicalization strategy. If <code>canonicalize</code> is <code>true</code>,
@@ -49,6 +53,11 @@ public abstract class PathCanonicalizationStrategy {
 						return file.getAbsolutePath();
 					}
 				}
+
+				@Override
+				protected boolean resolvesSymbolicLinksInternal() {
+					return true;
+				}
 			};
 		} else {
 			instance = new PathCanonicalizationStrategy() {
@@ -56,9 +65,15 @@ public abstract class PathCanonicalizationStrategy {
 				protected String getCanonicalPathInternal(File file) {
 					return file.getAbsolutePath();
 				}
+
+				@Override
+				protected boolean resolvesSymbolicLinksInternal() {
+					return false;
+				}
 			};
 		}
 	}
 
 	protected abstract String getCanonicalPathInternal(File file);
+	protected abstract boolean resolvesSymbolicLinksInternal();
 }
diff --git a/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/resources/ResourceLookup.java b/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/resources/ResourceLookup.java
index 6598ae9b5bf..803173b65fe 100644
--- a/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/resources/ResourceLookup.java
+++ b/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/core/resources/ResourceLookup.java
@@ -76,7 +76,7 @@ public class ResourceLookup {
 	 * 			NB the returned IFile may not exist
 	 */
 	public static IFile selectFileForLocationURI(URI location, IProject preferredProject) {
-		return selectFile(findFilesForLocationURI(location), preferredProject);
+		return selectFile(findFilesForLocationURI(location), preferredProject, location);
 	}
 
 	/**
@@ -89,7 +89,7 @@ public class ResourceLookup {
 	 * 			NB the returned IFile may not exist
 	 */
 	public static IFile selectFileForLocation(IPath location, IProject preferredProject) {
-		return selectFile(findFilesForLocation(location), preferredProject);
+		return selectFile(findFilesForLocation(location), preferredProject, location);
 	}
 
 	/**
@@ -102,7 +102,7 @@ public class ResourceLookup {
 	 * one that's most relevant, then first try to find it directly - before getting to the more expensive 
 	 * loop of computing the "relevance scores" for all the files.
 	 */
-	private static IFile selectFile(IFile[] files, IProject preferredProject) {
+	private static IFile selectFile(IFile[] files, IProject preferredProject, Object originalLocation) {
 		if (files.length == 0)
 			return null;
 
@@ -134,7 +134,7 @@ public class ResourceLookup {
 		int bestRelevance= -1;
 
 		for (IFile file : files) {
-			int relevance= FileRelevance.getRelevance(file, preferredProject);
+			int relevance= FileRelevance.getRelevance(file, preferredProject, PathCanonicalizationStrategy.resolvesSymbolicLinks(), originalLocation);
 			if (best == null || relevance > bestRelevance ||
 					(relevance == bestRelevance &&
 							best.getFullPath().toString().compareTo(file.getFullPath().toString()) > 0)) {