Fixes problem with single project repositories and GitFileHistory

The GitFileHistory class must consider empty relative path to project
for repositories that contain one single project and the project
contains the .git folder. This patch adds the necessary check to the
GitFileHistory class and a JUnit test that verifies that the fix works
as expected.

Bug: 356020
Change-Id: I1b4fc3d6e818f39a7c7e5450b7325cea0dcdcce4
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

2 files changed, 62 insertions, 3 deletions

diff --git a/org.eclipse.egit.core.test/src/org/eclipse/egit/core/internal/storage/BlobStorageTest.java b/org.eclipse.egit.core.test/src/org/eclipse/egit/core/internal/storage/BlobStorageTest.java
index 83c699592d..c1d8313df5 100644
--- a/org.eclipse.egit.core.test/src/org/eclipse/egit/core/internal/storage/BlobStorageTest.java
+++ b/org.eclipse.egit.core.test/src/org/eclipse/egit/core/internal/storage/BlobStorageTest.java
@@ -8,15 +8,33 @@
  *******************************************************************************/
 package org.eclipse.egit.core.internal.storage;
 
+import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.fail;
 
+import java.io.ByteArrayInputStream;
+import java.io.File;
+import java.util.Collections;
+
+import org.eclipse.core.resources.IFile;
+import org.eclipse.core.resources.IProject;
 import org.eclipse.core.runtime.CoreException;
+import org.eclipse.core.runtime.IProgressMonitor;
+import org.eclipse.core.runtime.NullProgressMonitor;
 import org.eclipse.core.runtime.Path;
+import org.eclipse.egit.core.Activator;
+import org.eclipse.egit.core.op.ConnectProviderOperation;
+import org.eclipse.egit.core.op.DisconnectProviderOperation;
 import org.eclipse.egit.core.test.GitTestCase;
+import org.eclipse.egit.core.test.TestProject;
+import org.eclipse.jgit.api.Git;
+import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.Repository;
+import org.eclipse.jgit.revwalk.RevCommit;
 import org.eclipse.jgit.storage.file.FileRepository;
+import org.eclipse.jgit.util.FileUtils;
+import org.eclipse.team.core.history.IFileHistory;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
@@ -49,6 +67,43 @@ public class BlobStorageTest extends GitTestCase {
 	}
 
 	@Test
+	public void testGitFileHistorySingleProjectOk() throws Exception {
+		IProgressMonitor progress = new NullProgressMonitor();
+		TestProject singleRepoProject = new TestProject(true, "Project-2");
+		IProject proj = singleRepoProject.getProject();
+		File singleProjectGitDir = new File(proj.getLocation().toFile(), Constants.DOT_GIT);
+		if (singleProjectGitDir.exists())
+			FileUtils.delete(singleProjectGitDir, FileUtils.RECURSIVE | FileUtils.RETRY);
+
+		Repository singleProjectRepo = new FileRepository(singleProjectGitDir);
+		singleProjectRepo.create();
+
+		// Repository must be mapped in order to test the GitFileHistory
+		Activator.getDefault().getRepositoryUtil().addConfiguredRepository(singleProjectGitDir);
+		ConnectProviderOperation connectOp = new ConnectProviderOperation(proj, singleProjectGitDir);
+		connectOp.execute(progress);
+
+		try {
+			IFile file = proj.getFile("file");
+			file.create(new ByteArrayInputStream("data".getBytes()), 0, progress);
+			Git git = new Git(singleProjectRepo);
+			git.add().addFilepattern(".").call();
+			RevCommit commit = git.commit().setAuthor("JUnit", "junit@jgit.org").setAll(true).setMessage("First commit").call();
+
+			GitFileHistoryProvider fhProvider = new GitFileHistoryProvider();
+			IFileHistory fh = fhProvider.getFileHistoryFor(singleRepoProject.getProject(), 0, null);
+			assertNotNull(fh);
+			assertEquals(fh.getFileRevisions().length, 1);
+			assertNotNull(fh.getFileRevision(commit.getId().getName()));
+		} finally {
+			DisconnectProviderOperation disconnectOp = new DisconnectProviderOperation(Collections.singletonList(proj));
+			disconnectOp.execute(progress);
+			Activator.getDefault().getRepositoryUtil().removeDir(singleProjectGitDir);
+			singleProjectRepo.close();
+		}
+	}
+
+	@Test
 	public void testFailNotFound() throws Exception {
 		BlobStorage blobStorage = new BlobStorage(repository, "file", ObjectId.fromString("0123456789012345678901234567890123456789"));
 		assertEquals("file", blobStorage.getName());
diff --git a/org.eclipse.egit.core/src/org/eclipse/egit/core/internal/storage/GitFileHistory.java b/org.eclipse.egit.core/src/org/eclipse/egit/core/internal/storage/GitFileHistory.java
index 451ca85345..5ee328d08b 100644
--- a/org.eclipse.egit.core/src/org/eclipse/egit/core/internal/storage/GitFileHistory.java
+++ b/org.eclipse.egit.core/src/org/eclipse/egit/core/internal/storage/GitFileHistory.java
@@ -66,9 +66,13 @@ class GitFileHistory extends FileHistory implements IAdaptable {
 			db = rm.getRepository();
 			walk = new KidWalk(db);
 			gitPath = rm.getRepoRelativePath(resource);
-			walk.setTreeFilter(AndTreeFilter.create(PathFilterGroup
-					.createFromStrings(Collections.singleton(gitPath)),
-					TreeFilter.ANY_DIFF));
+			if(gitPath == null || gitPath.isEmpty()) {
+				walk.setTreeFilter(TreeFilter.ANY_DIFF);
+			} else {
+				walk.setTreeFilter(AndTreeFilter.create(PathFilterGroup
+						.createFromStrings(Collections.singleton(gitPath)),
+						TreeFilter.ANY_DIFF));
+			}
 		}
 
 		revisions = buildRevisions(monitor, flags);