Fix findGitDir() with no ceiling directories

Bug: 322866
Change-Id: I64205bb0315a725dfa523ccff1796de50f465162
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
CC: Ketan Padegaonkar <KetanPadegaonkar@gmail.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

org.eclipse.jgit.test/tst/org/eclipse/jgit/storage/file/FileRepositoryBuilderTest.java

@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2010, Google Inc.
+ * 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.storage.file;
+
+import java.io.File;
+
+import org.eclipse.jgit.junit.LocalDiskRepositoryTestCase;
+
+public class FileRepositoryBuilderTest extends LocalDiskRepositoryTestCase {
+	public void testShouldAutomagicallyDetectGitDirectory() throws Exception {
+		FileRepository r = createWorkRepository();
+		File d = new File(r.getDirectory(), "sub-dir");
+		d.mkdir();
+
+		assertEquals(r.getDirectory(), new FileRepositoryBuilder()
+				.findGitDir(d).getGitDir());
+	}
+}

org.eclipse.jgit/src/org/eclipse/jgit/lib/BaseRepositoryBuilder.java

@@ -457,7 +457,8 @@ public class BaseRepositoryBuilder<B extends BaseRepositoryBuilder, R extends Re
 				}
 
 				current = current.getParentFile();
-				if (current != null && ceilingDirectories.contains(current))
+				if (current != null && ceilingDirectories != null
+						&& ceilingDirectories.contains(current))
 					break;
 			}
 		}