Changed TreeWalk.forPath(...) to work with recursive paths.

Previously, this method would not (always) work when a recursive path
such as "a/b" was passed into it.

Change-Id: I0752a1f5fc7fef32064d8f921b33187c0bdc7227
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>

org.eclipse.jgit.test/tst/org/eclipse/jgit/treewalk/ForPathTest.java

@@ -0,0 +1,147 @@
+/*
+ * Copyright (C) 2011, Garmin International
+ * Copyright (C) 2011, Jesse Greenwald <jesse.greenwald@gmail.com>
+ * and other copyright owners as documented in the project's IP log.
+ *
+ * This program and the accompanying materials are made available
+ * under the terms of the Eclipse Distribution License v1.0 which
+ * accompanies this distribution, is reproduced below, and is
+ * available at http://www.eclipse.org/org/documents/edl-v10.php
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials provided
+ *   with the distribution.
+ *
+ * - Neither the name of the Eclipse Foundation, Inc. nor the
+ *   names of its contributors may be used to endorse or promote
+ *   products derived from this software without specific prior
+ *   written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package org.eclipse.jgit.treewalk;
+
+import static org.junit.Assert.assertEquals;
+
+import org.eclipse.jgit.dircache.DirCache;
+import org.eclipse.jgit.dircache.DirCacheBuilder;
+import org.eclipse.jgit.dircache.DirCacheEntry;
+import org.eclipse.jgit.lib.Constants;
+import org.eclipse.jgit.lib.FileMode;
+import org.eclipse.jgit.lib.ObjectId;
+import org.eclipse.jgit.lib.ObjectInserter;
+import org.eclipse.jgit.lib.ObjectReader;
+import org.eclipse.jgit.lib.RepositoryTestCase;
+import org.junit.Test;
+
+public class ForPathTest extends RepositoryTestCase {
+
+	private static final FileMode SYMLINK = FileMode.SYMLINK;
+
+	private static final FileMode REGULAR_FILE = FileMode.REGULAR_FILE;
+
+	private static final FileMode EXECUTABLE_FILE = FileMode.EXECUTABLE_FILE;
+
+	private DirCacheEntry makeEntry(final String path, final FileMode mode)
+			throws Exception {
+		final DirCacheEntry ent = new DirCacheEntry(path);
+		ent.setFileMode(mode);
+		ent.setObjectId(new ObjectInserter.Formatter().idFor(
+				Constants.OBJ_BLOB, Constants.encode(path)));
+		return ent;
+	}
+
+	@Test
+	public void testFindObjects() throws Exception {
+		final DirCache tree0 = DirCache.newInCore();
+		final DirCacheBuilder b0 = tree0.builder();
+		ObjectReader or = db.newObjectReader();
+		ObjectInserter oi = db.newObjectInserter();
+
+		DirCacheEntry aDotB = makeEntry("a.b", EXECUTABLE_FILE);
+		b0.add(aDotB);
+		DirCacheEntry aSlashB = makeEntry("a/b", REGULAR_FILE);
+		b0.add(aSlashB);
+		DirCacheEntry aSlashCSlashD = makeEntry("a/c/d", REGULAR_FILE);
+		b0.add(aSlashCSlashD);
+		DirCacheEntry aZeroB = makeEntry("a0b", SYMLINK);
+		b0.add(aZeroB);
+		b0.finish();
+		assertEquals(4, tree0.getEntryCount());
+		ObjectId tree = tree0.writeTree(oi);
+
+		// Find the directories that were implicitly created above.
+		TreeWalk tw = new TreeWalk(or);
+		tw.addTree(tree);
+		ObjectId a = null;
+		ObjectId aSlashC = null;
+		while (tw.next()) {
+			if (tw.getPathString().equals("a")) {
+				a = tw.getObjectId(0);
+				tw.enterSubtree();
+				while (tw.next()) {
+					if (tw.getPathString().equals("a/c")) {
+						aSlashC = tw.getObjectId(0);
+						break;
+					}
+				}
+				break;
+			}
+		}
+
+		assertEquals(a, TreeWalk.forPath(or, "a", tree).getObjectId(0));
+		assertEquals(a, TreeWalk.forPath(or, "a/", tree).getObjectId(0));
+		assertEquals(null, TreeWalk.forPath(or, "/a", tree));
+		assertEquals(null, TreeWalk.forPath(or, "/a/", tree));
+
+		assertEquals(aDotB.getObjectId(), TreeWalk.forPath(or, "a.b", tree)
+				.getObjectId(0));
+		assertEquals(null, TreeWalk.forPath(or, "/a.b", tree));
+		assertEquals(null, TreeWalk.forPath(or, "/a.b/", tree));
+		assertEquals(aDotB.getObjectId(), TreeWalk.forPath(or, "a.b/", tree)
+				.getObjectId(0));
+
+		assertEquals(aZeroB.getObjectId(), TreeWalk.forPath(or, "a0b", tree)
+				.getObjectId(0));
+
+		assertEquals(aSlashB.getObjectId(), TreeWalk.forPath(or, "a/b", tree)
+				.getObjectId(0));
+		assertEquals(aSlashB.getObjectId(), TreeWalk.forPath(or, "b", a)
+				.getObjectId(0));
+
+		assertEquals(aSlashC, TreeWalk.forPath(or, "a/c", tree).getObjectId(0));
+		assertEquals(aSlashC, TreeWalk.forPath(or, "c", a).getObjectId(0));
+
+		assertEquals(aSlashCSlashD.getObjectId(),
+				TreeWalk.forPath(or, "a/c/d", tree).getObjectId(0));
+		assertEquals(aSlashCSlashD.getObjectId(), TreeWalk
+				.forPath(or, "c/d", a).getObjectId(0));
+
+		or.release();
+		oi.release();
+	}
+
+}

org.eclipse.jgit/src/org/eclipse/jgit/treewalk/TreeWalk.java

@@ -45,7 +45,6 @@
 package org.eclipse.jgit.treewalk;
 
 import java.io.IOException;
-import java.util.Collections;
 
 import org.eclipse.jgit.errors.CorruptObjectException;
 import org.eclipse.jgit.errors.IncorrectObjectTypeException;
@@ -59,7 +58,7 @@ import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.ObjectReader;
 import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.revwalk.RevTree;
-import org.eclipse.jgit.treewalk.filter.PathFilterGroup;
+import org.eclipse.jgit.treewalk.filter.PathFilter;
 import org.eclipse.jgit.treewalk.filter.TreeFilter;
 import org.eclipse.jgit.util.RawParseUtils;
 
@@ -114,12 +113,20 @@ public class TreeWalk {
 	public static TreeWalk forPath(final ObjectReader reader, final String path,
 			final AnyObjectId... trees) throws MissingObjectException,
 			IncorrectObjectTypeException, CorruptObjectException, IOException {
-		final TreeWalk r = new TreeWalk(reader);
+		TreeWalk tw = new TreeWalk(reader);
-		r.setFilter(PathFilterGroup.createFromStrings(Collections
+		PathFilter f = PathFilter.create(path);
-				.singleton(path)));
+		tw.setFilter(f);
-		r.setRecursive(r.getFilter().shouldBeRecursive());
+		tw.reset(trees);
-		r.reset(trees);
+		tw.setRecursive(false);
-		return r.next() ? r : null;
+
+		while (tw.next()) {
+			if (f.isDone(tw)) {
+				return tw;
+			} else if (tw.isSubtree()) {
+				tw.enterSubtree();
+			}
+		}
+		return null;
 	}
 
 	/**
@@ -748,6 +755,13 @@ public class TreeWalk {
 		return r;
 	}
 
+	/**
+	 * @return The path length of the current entry.
+	 */
+	public int getPathLength() {
+		return currentHead.pathLen;
+	}
+
 	/**
 	 * Test if the supplied path matches the current entry's path.
 	 * <p>

org.eclipse.jgit/src/org/eclipse/jgit/treewalk/filter/PathFilter.java

@@ -116,4 +116,14 @@ public class PathFilter extends TreeFilter {
 	public String toString() {
 		return "PATH(\"" + pathStr + "\")";
 	}
+
+	/**
+	 * @param walker
+	 *            The walk to check against.
+	 * @return {@code true} if the path length of this filter matches the length
+	 *         of the current path of the supplied TreeWalk.
+	 */
+	public boolean isDone(final TreeWalk walker) {
+		return pathRaw.length == walker.getPathLength();
+	}
 }