Revert 4678f4b and provide another solution for bug 467631

Making gitlinks and folders match in a tree walk was the wrong
approach to fix bug 467631. The problem is that in such a conflict
the tree walk may then not descend into the folder.

Revert the changes to Paths.java and PathsTest.java from commit
4678f4b. Instead test for the problem case from bug 467631 explicitly
in IndexDiff. Add Daniel's test case from bug 545162, and add yet
another test case for DiffEntry.scan() that covers the problem
originally reported in bug 545162.

Bug: 545162
Change-Id: Ie2214c5d5ee32ac6596b621f0f1c7b86d38fa9b7
Also-by: Daniel Veihelmann <daniel.veihelmann@gmail.com>
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

3 files changed, 96 insertions, 19 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/diff/DiffEntryTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/diff/DiffEntryTest.java
index 73c230ac68..de768118bf 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/diff/DiffEntryTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/diff/DiffEntryTest.java
@@ -59,9 +59,12 @@ import org.eclipse.jgit.diff.DiffEntry.ChangeType;
 import org.eclipse.jgit.dircache.DirCache;
 import org.eclipse.jgit.dircache.DirCacheEditor;
 import org.eclipse.jgit.dircache.DirCacheEditor.PathEdit;
+import org.eclipse.jgit.internal.storage.file.FileRepository;
 import org.eclipse.jgit.dircache.DirCacheEntry;
+import org.eclipse.jgit.junit.JGitTestUtil;
 import org.eclipse.jgit.junit.RepositoryTestCase;
 import org.eclipse.jgit.lib.FileMode;
+import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.revwalk.RevCommit;
 import org.eclipse.jgit.treewalk.EmptyTreeIterator;
 import org.eclipse.jgit.treewalk.FileTreeIterator;
@@ -417,4 +420,64 @@ public class DiffEntryTest extends RepositoryTestCase {
 			assertEquals(FileMode.REGULAR_FILE, diff.getOldMode());
 		}
 	}
+
+	@Test
+	public void shouldReportSubmoduleReplacedByFileMove() throws Exception {
+		// Create a submodule
+		FileRepository submoduleStandalone = createWorkRepository();
+		JGitTestUtil.writeTrashFile(submoduleStandalone, "fileInSubmodule",
+				"submodule");
+		Git submoduleStandaloneGit = Git.wrap(submoduleStandalone);
+		submoduleStandaloneGit.add().addFilepattern("fileInSubmodule").call();
+		submoduleStandaloneGit.commit().setMessage("add file to submodule")
+				.call();
+
+		Repository submodule_db = Git.wrap(db).submoduleAdd()
+				.setPath("modules/submodule")
+				.setURI(submoduleStandalone.getDirectory().toURI().toString())
+				.call();
+		File submodule_trash = submodule_db.getWorkTree();
+		addRepoToClose(submodule_db);
+		writeTrashFile("fileInRoot", "root");
+		Git rootGit = Git.wrap(db);
+		rootGit.add().addFilepattern("fileInRoot").call();
+		rootGit.commit().setMessage("add submodule and root file").call();
+		// Dummy change on fileInRoot
+		writeTrashFile("fileInRoot", "changed");
+		rootGit.add().addFilepattern("fileInRoot").call();
+		RevCommit firstCommit = rootGit.commit().setMessage("change root file")
+				.call();
+		// Remove the submodule again and move fileInRoot into that subfolder
+		rootGit.rm().setCached(true).addFilepattern("modules/submodule").call();
+		recursiveDelete(submodule_trash);
+		JGitTestUtil.deleteTrashFile(db, "fileInRoot");
+		// Move the fileInRoot file
+		writeTrashFile("modules/submodule/fileInRoot", "changed");
+		rootGit.rm().addFilepattern("fileInRoot").addFilepattern("modules/")
+				.call();
+		rootGit.add().addFilepattern("modules/").call();
+		RevCommit secondCommit = rootGit.commit()
+				.setMessage("remove submodule and move root file")
+				.call();
+		// Diff should report submodule having been deleted and file moved
+		// (deleted and added)
+		try (TreeWalk walk = new TreeWalk(db)) {
+			walk.addTree(firstCommit.getTree());
+			walk.addTree(secondCommit.getTree());
+			walk.setRecursive(true);
+			List<DiffEntry> diffs = DiffEntry.scan(walk);
+			assertEquals(3, diffs.size());
+			DiffEntry e = diffs.get(0);
+			assertEquals(DiffEntry.ChangeType.DELETE, e.getChangeType());
+			assertEquals("fileInRoot", e.getOldPath());
+			e = diffs.get(1);
+			assertEquals(DiffEntry.ChangeType.DELETE, e.getChangeType());
+			assertEquals("modules/submodule", e.getOldPath());
+			assertEquals(FileMode.GITLINK, e.getOldMode());
+			e = diffs.get(2);
+			assertEquals(DiffEntry.ChangeType.ADD, e.getChangeType());
+			assertEquals("modules/submodule/fileInRoot", e.getNewPath());
+		}
+
+	}
 }
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/IndexDiffSubmoduleTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/IndexDiffSubmoduleTest.java
index 93ada4f301..fa7f5ab522 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/IndexDiffSubmoduleTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/IndexDiffSubmoduleTest.java
@@ -43,12 +43,14 @@
 
 package org.eclipse.jgit.lib;
 
+import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 
 import java.io.File;
 import java.io.IOException;
+import java.util.Arrays;
 import java.util.Set;
 
 import org.eclipse.jgit.api.CloneCommand;
@@ -128,7 +130,8 @@ public class IndexDiffSubmoduleTest extends RepositoryTestCase {
 		IndexDiff indexDiff = new IndexDiff(db2, Constants.HEAD,
 				new FileTreeIterator(db2));
 		indexDiff.setIgnoreSubmoduleMode(mode);
-		assertFalse(indexDiff.diff());
+		boolean changed = indexDiff.diff();
+		assertFalse(changed);
 	}
 
 	@Theory
@@ -263,4 +266,33 @@ public class IndexDiffSubmoduleTest extends RepositoryTestCase {
 		assertDiff(indexDiff, mode, IgnoreSubmoduleMode.ALL,
 				IgnoreSubmoduleMode.DIRTY, IgnoreSubmoduleMode.UNTRACKED);
 	}
+
+	@Theory
+	public void testSubmoduleReplacedByMovedFile(IgnoreSubmoduleMode mode)
+			throws Exception {
+		Git git = Git.wrap(db);
+		git.rm().setCached(true).addFilepattern("modules/submodule").call();
+		recursiveDelete(submodule_trash);
+		JGitTestUtil.deleteTrashFile(db, "fileInRoot");
+		// Move the fileInRoot file
+		writeTrashFile("modules/submodule/fileInRoot", "root");
+		git.rm().addFilepattern("fileInRoot").addFilepattern("modules/").call();
+		git.add().addFilepattern("modules/").call();
+		IndexDiff indexDiff = new IndexDiff(db, Constants.HEAD,
+				new FileTreeIterator(db));
+		indexDiff.setIgnoreSubmoduleMode(mode);
+		assertTrue(indexDiff.diff());
+		String[] removed = indexDiff.getRemoved().toArray(new String[0]);
+		Arrays.sort(removed);
+		if (IgnoreSubmoduleMode.ALL.equals(mode)) {
+			assertArrayEquals(new String[] { "fileInRoot" }, removed);
+		} else {
+			assertArrayEquals(
+					new String[] { "fileInRoot", "modules/submodule" },
+					removed);
+		}
+		assertEquals("[modules/submodule/fileInRoot]",
+				indexDiff.getAdded().toString());
+	}
+
 }
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/PathsTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/PathsTest.java
index f78cbe2601..7542ec8910 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/PathsTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/PathsTest.java
@@ -89,29 +89,14 @@ public class PathsTest {
 				a, 0, a.length, FileMode.TREE.getBits(),
 				b, 0, b.length, FileMode.TREE.getBits()));
 		assertEquals(0, compare(
-				a, 0, a.length, FileMode.TREE.getBits(),
-				b, 0, b.length, FileMode.GITLINK.getBits()));
-		assertEquals(0, compare(
-				a, 0, a.length, FileMode.GITLINK.getBits(),
-				b, 0, b.length, FileMode.GITLINK.getBits()));
-		assertEquals(0, compare(
-				a, 0, a.length, FileMode.GITLINK.getBits(),
-				b, 0, b.length, FileMode.TREE.getBits()));
-		assertEquals(0, compare(
 				a, 0, a.length, FileMode.REGULAR_FILE.getBits(),
 				b, 0, b.length, FileMode.REGULAR_FILE.getBits()));
 		assertEquals(-47, compare(
 				a, 0, a.length, FileMode.REGULAR_FILE.getBits(),
 				b, 0, b.length, FileMode.TREE.getBits()));
-		assertEquals(0, compare(
-				a, 0, a.length, FileMode.REGULAR_FILE.getBits(),
-				b, 0, b.length, FileMode.GITLINK.getBits()));
 		assertEquals(47, compare(
 				a, 0, a.length, FileMode.TREE.getBits(),
 				b, 0, b.length, FileMode.REGULAR_FILE.getBits()));
-		assertEquals(0, compare(
-				a, 0, a.length, FileMode.GITLINK.getBits(),
-				b, 0, b.length, FileMode.REGULAR_FILE.getBits()));
 
 		assertEquals(0, compareSameName(
 				a, 0, a.length,
@@ -119,9 +104,6 @@ public class PathsTest {
 		assertEquals(0, compareSameName(
 				a, 0, a.length,
 				b, 0, b.length, FileMode.REGULAR_FILE.getBits()));
-		assertEquals(0, compareSameName(
-				a, 0, a.length,
-				b, 0, b.length, FileMode.GITLINK.getBits()));
 
 		a = Constants.encode("a.c");
 		b = Constants.encode("a");