Implement DIR_NO_GITLINKS

Implement the DIR_NO_GITLINKS setting with the same functionality
it provides in cGit.

Bug: 436200
Change-Id: I8304e42df2d7e8d7925f515805e075a92ff6ce28
Signed-off-by: Preben Ingvaldsen <preben@puppetlabs.com>

7 files changed, 99 insertions, 11 deletions

diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/api/AddCommand.java b/org.eclipse.jgit/src/org/eclipse/jgit/api/AddCommand.java
index 3b94f16f1a..1f37833a41 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/api/AddCommand.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/api/AddCommand.java
@@ -45,6 +45,7 @@ package org.eclipse.jgit.api;
 
 import static org.eclipse.jgit.lib.Constants.OBJ_BLOB;
 import static org.eclipse.jgit.lib.FileMode.GITLINK;
+import static org.eclipse.jgit.lib.FileMode.TYPE_GITLINK;
 import static org.eclipse.jgit.lib.FileMode.TYPE_TREE;
 
 import java.io.IOException;
@@ -201,7 +202,10 @@ public class AddCommand extends GitCommand<DirCache> {
 					continue;
 				}
 
-				if (f.getEntryRawMode() == TYPE_TREE) {
+				if ((f.getEntryRawMode() == TYPE_TREE
+						&& f.getIndexFileMode(c) != FileMode.GITLINK) ||
+						(f.getEntryRawMode() == TYPE_GITLINK
+								&& f.getIndexFileMode(c) == FileMode.TREE)) {
 					// Index entry exists and is symlink, gitlink or file,
 					// otherwise the tree would have been entered above.
 					// Replace the index entry by diving into tree of files.
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/lib/ConfigConstants.java b/org.eclipse.jgit/src/org/eclipse/jgit/lib/ConfigConstants.java
index 054d193017..abc8c269ff 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/lib/ConfigConstants.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/lib/ConfigConstants.java
@@ -235,6 +235,12 @@ public class ConfigConstants {
 	 */
 	public static final String CONFIG_KEY_HIDEDOTFILES = "hidedotfiles";
 
+	/**
+	 * The "dirnogitlinks" key
+	 * @since 4.3
+	 */
+	public static final String CONFIG_KEY_DIRNOGITLINKS = "dirNoGitLinks";
+
 	/** The "precomposeunicode" key */
 	public static final String CONFIG_KEY_PRECOMPOSEUNICODE = "precomposeunicode";
 
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/AbstractTreeIterator.java b/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/AbstractTreeIterator.java
index dc835e4f36..07fc829db4 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/AbstractTreeIterator.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/AbstractTreeIterator.java
@@ -729,4 +729,13 @@ public abstract class AbstractTreeIterator {
 	public String toString() {
 		return getClass().getSimpleName() + "[" + getEntryPathString() + "]"; //$NON-NLS-1$
 	}
+
+	/**
+	 * @return whether or not this Iterator is iterating through the Work Tree
+	 *
+	 * @since 4.3
+	 */
+	public boolean isWorkTree() {
+		return false;
+	}
 }
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/FileTreeIterator.java b/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/FileTreeIterator.java
index eb4f1a87d0..db81e1af9b 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/FileTreeIterator.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/FileTreeIterator.java
@@ -94,7 +94,10 @@ public class FileTreeIterator extends WorkingTreeIterator {
 	 *            the repository whose working tree will be scanned.
 	 */
 	public FileTreeIterator(Repository repo) {
-		this(repo, DefaultFileModeStrategy.INSTANCE);
+		this(repo,
+				repo.getConfig().get(WorkingTreeOptions.KEY).isDirNoGitLinks() ?
+						NoGitlinksStrategy.INSTANCE :
+						DefaultFileModeStrategy.INSTANCE);
 	}
 
 	/**
@@ -291,6 +294,35 @@ public class FileTreeIterator extends WorkingTreeIterator {
 		}
 	}
 
+	/**
+	 * A FileModeStrategy that implements native git's DIR_NO_GITLINKS
+	 * behavior. This is the same as the default FileModeStrategy, except
+	 * all directories will be treated as directories regardless of whether
+	 * or not they contain a .git directory or file.
+	 *
+	 * @since 4.3
+	 */
+	static public class NoGitlinksStrategy implements FileModeStrategy {
+
+		/**
+		 * a singleton instance of the default FileModeStrategy
+		 */
+		public final static NoGitlinksStrategy INSTANCE = new NoGitlinksStrategy();
+
+		@Override
+		public FileMode getMode(File f, FS.Attributes attributes) {
+			if (attributes.isSymbolicLink()) {
+				return FileMode.SYMLINK;
+			} else if (attributes.isDirectory()) {
+				return FileMode.TREE;
+			} else if (attributes.isExecutable()) {
+				return FileMode.EXECUTABLE_FILE;
+			} else {
+				return FileMode.REGULAR_FILE;
+			}
+		}
+	}
+
 
 	/**
 	 * Wrapper for a standard Java IO file
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/TreeWalk.java b/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/TreeWalk.java
index aecbac11ea..501d676735 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/TreeWalk.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/TreeWalk.java
@@ -1187,7 +1187,12 @@ public class TreeWalk implements AutoCloseable, AttributesProvider {
 		for (int i = 0; i < trees.length; i++) {
 			final AbstractTreeIterator t = trees[i];
 			final AbstractTreeIterator n;
-			if (t.matches == ch && !t.eof() && FileMode.TREE.equals(t.mode))
+			// If we find a GITLINK when attempting to enter a subtree, then the
+			// GITLINK must exist as a TREE in the index, meaning the working tree
+			// entry should be treated as a TREE
+			if (t.matches == ch && !t.eof() &&
+					(FileMode.TREE.equals(t.mode)
+							|| (FileMode.GITLINK.equals(t.mode) && t.isWorkTree())))
 				n = t.createSubtreeIterator(reader, idBuffer);
 			else
 				n = t.createEmptyTreeIterator();
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/WorkingTreeIterator.java b/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/WorkingTreeIterator.java
index ca8f9aa373..39176c621e 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/WorkingTreeIterator.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/WorkingTreeIterator.java
@@ -264,7 +264,7 @@ public abstract class WorkingTreeIterator extends AbstractTreeIterator {
 			// the cached index information for the path.
 			//
 			DirCacheIterator i = state.walk.getTree(state.dirCacheTree,
-					DirCacheIterator.class);
+							DirCacheIterator.class);
 			if (i != null) {
 				DirCacheEntry ent = i.getDirCacheEntry();
 				if (ent != null && compareMetadata(ent) == MetadataDiff.EQUAL) {
@@ -289,6 +289,11 @@ public abstract class WorkingTreeIterator extends AbstractTreeIterator {
 		return zeroid;
 	}
 
+	@Override
+	public boolean isWorkTree() {
+		return true;
+	}
+
 	/**
 	 * Get submodule id for given entry.
 	 *
@@ -916,17 +921,31 @@ public abstract class WorkingTreeIterator extends AbstractTreeIterator {
 	 */
 	public FileMode getIndexFileMode(final DirCacheIterator indexIter) {
 		final FileMode wtMode = getEntryFileMode();
-		if (indexIter == null)
-			return wtMode;
-		if (getOptions().isFileMode())
+		if (indexIter == null) {
 			return wtMode;
+		}
 		final FileMode iMode = indexIter.getEntryFileMode();
-		if (FileMode.REGULAR_FILE == wtMode
-				&& FileMode.EXECUTABLE_FILE == iMode)
+		if (getOptions().isFileMode() && iMode != FileMode.GITLINK && iMode != FileMode.TREE) {
+			return wtMode;
+		}
+		if (!getOptions().isFileMode()) {
+			if (FileMode.REGULAR_FILE == wtMode
+					&& FileMode.EXECUTABLE_FILE == iMode) {
+				return iMode;
+			}
+			if (FileMode.EXECUTABLE_FILE == wtMode
+					&& FileMode.REGULAR_FILE == iMode) {
+				return iMode;
+			}
+		}
+		if (FileMode.GITLINK == iMode
+				&& FileMode.TREE == wtMode) {
 			return iMode;
-		if (FileMode.EXECUTABLE_FILE == wtMode
-				&& FileMode.REGULAR_FILE == iMode)
+		}
+		if (FileMode.TREE == iMode
+				&& FileMode.GITLINK == wtMode) {
 			return iMode;
+		}
 		return wtMode;
 	}
 
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/WorkingTreeOptions.java b/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/WorkingTreeOptions.java
index a8990b1e95..dea07c1973 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/WorkingTreeOptions.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/treewalk/WorkingTreeOptions.java
@@ -73,6 +73,8 @@ public class WorkingTreeOptions {
 
 	private final HideDotFiles hideDotFiles;
 
+	private final boolean dirNoGitLinks;
+
 	private WorkingTreeOptions(final Config rc) {
 		fileMode = rc.getBoolean(ConfigConstants.CONFIG_CORE_SECTION,
 				ConfigConstants.CONFIG_KEY_FILEMODE, true);
@@ -87,6 +89,9 @@ public class WorkingTreeOptions {
 		hideDotFiles = rc.getEnum(ConfigConstants.CONFIG_CORE_SECTION, null,
 				ConfigConstants.CONFIG_KEY_HIDEDOTFILES,
 				HideDotFiles.DOTGITONLY);
+		dirNoGitLinks = rc.getBoolean(ConfigConstants.CONFIG_CORE_SECTION, null,
+				ConfigConstants.CONFIG_KEY_DIRNOGITLINKS,
+				false);
 	}
 
 	/** @return true if the execute bit on working files should be trusted. */
@@ -131,4 +136,12 @@ public class WorkingTreeOptions {
 	public HideDotFiles getHideDotFiles() {
 		return hideDotFiles;
 	}
+
+	/**
+	 * @return whether or not we treat nested repos as directories.
+	 * 		   If true, folders containing .git entries will not be
+	 * 		   treated as gitlinks.
+	 * @since 4.3
+	 */
+	public boolean isDirNoGitLinks() { return dirNoGitLinks; }
 }