org.eclipse.jgit/src/org/eclipse/jgit/attributes/AttributesHandler.java - sop/jgit - Git at Google

 /*
  * Copyright (C) 2015, Ivan Motsch <ivan.motsch@bsiag.com>
  *
  * 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.attributes;

 import java.io.IOException;
 import java.util.HashMap;
 import java.util.List;
 import java.util.ListIterator;
 import java.util.Map;

 import org.eclipse.jgit.annotations.Nullable;
 import org.eclipse.jgit.attributes.Attribute.State;
 import org.eclipse.jgit.dircache.DirCacheIterator;
 import org.eclipse.jgit.lib.FileMode;
 import org.eclipse.jgit.treewalk.AbstractTreeIterator;
 import org.eclipse.jgit.treewalk.CanonicalTreeParser;
 import org.eclipse.jgit.treewalk.TreeWalk;
 import org.eclipse.jgit.treewalk.TreeWalk.OperationType;
 import org.eclipse.jgit.treewalk.WorkingTreeIterator;

 /**
  * The attributes handler knows how to retrieve, parse and merge attributes from
  * the various gitattributes files. Furthermore it collects and expands macro
  * expressions. The method {@link #getAttributes()} yields the ready processed
  * attributes for the current path represented by the {@link TreeWalk}
  * <p>
  * The implementation is based on the specifications in
  * http://git-scm.com/docs/gitattributes
  *
  * @since 4.3
  */
 public class AttributesHandler {
 	private static final String MACRO_PREFIX = "[attr]"; //$NON-NLS-1$

 	private static final String BINARY_RULE_KEY = "binary"; //$NON-NLS-1$

 	/**
 	 * This is the default <b>binary</b> rule that is present in any git folder
 	 * <code>[attr]binary -diff -merge -text</code>
 	 */
 	private static final List<Attribute> BINARY_RULE_ATTRIBUTES = new AttributesRule(
 			MACRO_PREFIX + BINARY_RULE_KEY, "-diff -merge -text") //$NON-NLS-1$
 					.getAttributes();

 	private final TreeWalk treeWalk;

 	private final AttributesNode globalNode;

 	private final AttributesNode infoNode;

 	private final Map<String, List<Attribute>> expansions = new HashMap<>();

 	/**
 	 * Create an {@link AttributesHandler} with default rules as well as merged
 	 * rules from global, info and worktree root attributes
 	 *
 	 * @param treeWalk
 	 * @throws IOException
 	 */
 	public AttributesHandler(TreeWalk treeWalk) throws IOException {
 		this.treeWalk = treeWalk;
 		AttributesNodeProvider attributesNodeProvider =treeWalk.getAttributesNodeProvider();
 		this.globalNode = attributesNodeProvider != null
 				? attributesNodeProvider.getGlobalAttributesNode() : null;
 		this.infoNode = attributesNodeProvider != null
 				? attributesNodeProvider.getInfoAttributesNode() : null;

 		AttributesNode rootNode = attributesNode(treeWalk,
 				rootOf(
 						treeWalk.getTree(WorkingTreeIterator.class)),
 				rootOf(
 						treeWalk.getTree(DirCacheIterator.class)),
 				rootOf(treeWalk
 						.getTree(CanonicalTreeParser.class)));

 		expansions.put(BINARY_RULE_KEY, BINARY_RULE_ATTRIBUTES);
 		for (AttributesNode node : new AttributesNode[] { globalNode, rootNode,
 				infoNode }) {
 			if (node == null) {
 				continue;
 			}
 			for (AttributesRule rule : node.getRules()) {
 				if (rule.getPattern().startsWith(MACRO_PREFIX)) {
 					expansions.put(rule.getPattern()
 							.substring(MACRO_PREFIX.length()).trim(),
 							rule.getAttributes());
 				}
 			}
 		}
 	}

 	/**
 	 * see {@link TreeWalk#getAttributes()}
 	 *
 	 * @return the {@link Attributes} for the current path represented by the
 	 *         {@link TreeWalk}
 	 * @throws IOException
 	 */
 	public Attributes getAttributes() throws IOException {
 		String entryPath = treeWalk.getPathString();
 		boolean isDirectory = (treeWalk.getFileMode() == FileMode.TREE);
 		Attributes attributes = new Attributes();

 		// Gets the info attributes
 		mergeInfoAttributes(entryPath, isDirectory, attributes);

 		// Gets the attributes located on the current entry path
 		mergePerDirectoryEntryAttributes(entryPath, entryPath.lastIndexOf('/'),
 				isDirectory,
 				treeWalk.getTree(WorkingTreeIterator.class),
 				treeWalk.getTree(DirCacheIterator.class),
 				treeWalk.getTree(CanonicalTreeParser.class),
 				attributes);

 		// Gets the attributes located in the global attribute file
 		mergeGlobalAttributes(entryPath, isDirectory, attributes);

 		// now after all attributes are collected - in the correct hierarchy
 		// order - remove all unspecified entries (the ! marker)
 		for (Attribute a : attributes.getAll()) {
 			if (a.getState() == State.UNSPECIFIED)
 				attributes.remove(a.getKey());
 		}

 		return attributes;
 	}

 	/**
 	 * Merges the matching GLOBAL attributes for an entry path.
 	 *
 	 * @param entryPath
 	 *            the path to test. The path must be relative to this attribute
 	 *            node's own repository path, and in repository path format
 	 *            (uses '/' and not '\').
 	 * @param isDirectory
 	 *            true if the target item is a directory.
 	 * @param result
 	 *            that will hold the attributes matching this entry path. This
 	 *            method will NOT override any existing entry in attributes.
 	 */
 	private void mergeGlobalAttributes(String entryPath, boolean isDirectory,
 			Attributes result) {
 		mergeAttributes(globalNode, entryPath, isDirectory, result);
 	}

 	/**
 	 * Merges the matching INFO attributes for an entry path.
 	 *
 	 * @param entryPath
 	 *            the path to test. The path must be relative to this attribute
 	 *            node's own repository path, and in repository path format
 	 *            (uses '/' and not '\').
 	 * @param isDirectory
 	 *            true if the target item is a directory.
 	 * @param result
 	 *            that will hold the attributes matching this entry path. This
 	 *            method will NOT override any existing entry in attributes.
 	 */
 	private void mergeInfoAttributes(String entryPath, boolean isDirectory,
 			Attributes result) {
 		mergeAttributes(infoNode, entryPath, isDirectory, result);
 	}

 	/**
 	 * Merges the matching working directory attributes for an entry path.
 	 *
 	 * @param entryPath
 	 *            the path to test. The path must be relative to this attribute
 	 *            node's own repository path, and in repository path format
 	 *            (uses '/' and not '\').
 	 * @param nameRoot
 	 *            index of the '/' preceeding the current level, or -1 if none
 	 * @param isDirectory
 	 *            true if the target item is a directory.
 	 * @param workingTreeIterator
 	 * @param dirCacheIterator
 	 * @param otherTree
 	 * @param result
 	 *            that will hold the attributes matching this entry path. This
 	 *            method will NOT override any existing entry in attributes.
 	 * @throws IOException
 	 */
 	private void mergePerDirectoryEntryAttributes(String entryPath,
 			int nameRoot, boolean isDirectory,
 			@Nullable WorkingTreeIterator workingTreeIterator,
 			@Nullable DirCacheIterator dirCacheIterator,
 			@Nullable CanonicalTreeParser otherTree, Attributes result)
 					throws IOException {
 		// Prevents infinite recurrence
 		if (workingTreeIterator != null || dirCacheIterator != null
 				|| otherTree != null) {
 			AttributesNode attributesNode = attributesNode(
 					treeWalk, workingTreeIterator, dirCacheIterator, otherTree);
 			if (attributesNode != null) {
 				mergeAttributes(attributesNode,
 						entryPath.substring(nameRoot + 1), isDirectory,
 						result);
 			}
 			mergePerDirectoryEntryAttributes(entryPath,
 					entryPath.lastIndexOf('/', nameRoot - 1), isDirectory,
 					parentOf(workingTreeIterator), parentOf(dirCacheIterator),
 					parentOf(otherTree), result);
 		}
 	}

 	/**
 	 * Merges the matching node attributes for an entry path.
 	 *
 	 * @param node
 	 *            the node to scan for matches to entryPath
 	 * @param entryPath
 	 *            the path to test. The path must be relative to this attribute
 	 *            node's own repository path, and in repository path format
 	 *            (uses '/' and not '\').
 	 * @param isDirectory
 	 *            true if the target item is a directory.
 	 * @param result
 	 *            that will hold the attributes matching this entry path. This
 	 *            method will NOT override any existing entry in attributes.
 	 */
 	protected void mergeAttributes(@Nullable AttributesNode node,
 			String entryPath,
 			boolean isDirectory, Attributes result) {
 		if (node == null)
 			return;
 		List<AttributesRule> rules = node.getRules();
 		// Parse rules in the reverse order that they were read since the last
 		// entry should be used
 		ListIterator<AttributesRule> ruleIterator = rules
 				.listIterator(rules.size());
 		while (ruleIterator.hasPrevious()) {
 			AttributesRule rule = ruleIterator.previous();
 			if (rule.isMatch(entryPath, isDirectory)) {
 				ListIterator<Attribute> attributeIte = rule.getAttributes()
 						.listIterator(rule.getAttributes().size());
 				// Parses the attributes in the reverse order that they were
 				// read since the last entry should be used
 				while (attributeIte.hasPrevious()) {
 					expandMacro(attributeIte.previous(), result);
 				}
 			}
 		}
 	}

 	/**
 	 * @param attr
 	 * @param result
 	 *            contains the (recursive) expanded and merged macro attributes
 	 *            including the attribute iself
 	 */
 	protected void expandMacro(Attribute attr, Attributes result) {
 		// loop detection = exists check
 		if (result.containsKey(attr.getKey()))
 			return;

 		// also add macro to result set, same does native git
 		result.put(attr);

 		List<Attribute> expansion = expansions.get(attr.getKey());
 		if (expansion == null) {
 			return;
 		}
 		switch (attr.getState()) {
 		case UNSET: {
 			for (Attribute e : expansion) {
 				switch (e.getState()) {
 				case SET:
 					expandMacro(new Attribute(e.getKey(), State.UNSET), result);
 					break;
 				case UNSET:
 					expandMacro(new Attribute(e.getKey(), State.SET), result);
 					break;
 				case UNSPECIFIED:
 					expandMacro(new Attribute(e.getKey(), State.UNSPECIFIED),
 							result);
 					break;
 				case CUSTOM:
 				default:
 					expandMacro(e, result);
 				}
 			}
 			break;
 		}
 		case CUSTOM: {
 			for (Attribute e : expansion) {
 				switch (e.getState()) {
 				case SET:
 				case UNSET:
 				case UNSPECIFIED:
 					expandMacro(e, result);
 					break;
 				case CUSTOM:
 				default:
 					expandMacro(new Attribute(e.getKey(), attr.getValue()),
 							result);
 				}
 			}
 			break;
 		}
 		case UNSPECIFIED: {
 			for (Attribute e : expansion) {
 				expandMacro(new Attribute(e.getKey(), State.UNSPECIFIED),
 						result);
 			}
 			break;
 		}
 		case SET:
 		default:
 			for (Attribute e : expansion) {
 				expandMacro(e, result);
 			}
 			break;
 		}
 	}

 	/**
 	 * Get the {@link AttributesNode} for the current entry.
 	 * <p>
 	 * This method implements the fallback mechanism between the index and the
 	 * working tree depending on the operation type
 	 * </p>
 	 *
 	 * @param treeWalk
 	 * @param workingTreeIterator
 	 * @param dirCacheIterator
 	 * @param otherTree
 	 * @return a {@link AttributesNode} of the current entry,
 	 *         {@link NullPointerException} otherwise.
 	 * @throws IOException
 	 *             It raises an {@link IOException} if a problem appears while
 	 *             parsing one on the attributes file.
 	 */
 	private static AttributesNode attributesNode(TreeWalk treeWalk,
 			@Nullable WorkingTreeIterator workingTreeIterator,
 			@Nullable DirCacheIterator dirCacheIterator,
 			@Nullable CanonicalTreeParser otherTree) throws IOException {
 		AttributesNode attributesNode = null;
 		switch (treeWalk.getOperationType()) {
 		case CHECKIN_OP:
 			if (workingTreeIterator != null) {
 				attributesNode = workingTreeIterator.getEntryAttributesNode();
 			}
 			if (attributesNode == null && dirCacheIterator != null) {
 				attributesNode = dirCacheIterator
 						.getEntryAttributesNode(treeWalk.getObjectReader());
 			}
 			if (attributesNode == null && otherTree != null) {
 				attributesNode = otherTree
 						.getEntryAttributesNode(treeWalk.getObjectReader());
 			}
 			break;
 		case CHECKOUT_OP:
 			if (otherTree != null) {
 				attributesNode = otherTree
 						.getEntryAttributesNode(treeWalk.getObjectReader());
 			}
 			if (attributesNode == null && dirCacheIterator != null) {
 				attributesNode = dirCacheIterator
 						.getEntryAttributesNode(treeWalk.getObjectReader());
 			}
 			if (attributesNode == null && workingTreeIterator != null) {
 				attributesNode = workingTreeIterator.getEntryAttributesNode();
 			}
 			break;
 		default:
 			throw new IllegalStateException(
 					"The only supported operation types are:" //$NON-NLS-1$
 							+ OperationType.CHECKIN_OP + "," //$NON-NLS-1$
 							+ OperationType.CHECKOUT_OP);
 		}

 		return attributesNode;
 	}

 	private static <T extends AbstractTreeIterator> T parentOf(@Nullable T node) {
 		if(node==null) return null;
 		@SuppressWarnings("unchecked")
 		Class<T> type = (Class<T>) node.getClass();
 		AbstractTreeIterator parent = node.parent;
 		if (type.isInstance(parent)) {
 			return type.cast(parent);
 		}
 		return null;
 	}

 	private static <T extends AbstractTreeIterator> T rootOf(
 			@Nullable T node) {
 		if(node==null) return null;
 		AbstractTreeIterator t=node;
 		while (t!= null && t.parent != null) {
 			t= t.parent;
 		}
 		@SuppressWarnings("unchecked")
 		Class<T> type = (Class<T>) node.getClass();
 		if (type.isInstance(t)) {
 			return type.cast(t);
 		}
 		return null;
 	}

 }
	/*
	* Copyright (C) 2015, Ivan Motsch <ivan.motsch@bsiag.com>
	*
	* 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.attributes;

	import java.io.IOException;
	import java.util.HashMap;
	import java.util.List;
	import java.util.ListIterator;
	import java.util.Map;

	import org.eclipse.jgit.annotations.Nullable;
	import org.eclipse.jgit.attributes.Attribute.State;
	import org.eclipse.jgit.dircache.DirCacheIterator;
	import org.eclipse.jgit.lib.FileMode;
	import org.eclipse.jgit.treewalk.AbstractTreeIterator;
	import org.eclipse.jgit.treewalk.CanonicalTreeParser;
	import org.eclipse.jgit.treewalk.TreeWalk;
	import org.eclipse.jgit.treewalk.TreeWalk.OperationType;
	import org.eclipse.jgit.treewalk.WorkingTreeIterator;

	/**
	* The attributes handler knows how to retrieve, parse and merge attributes from
	* the various gitattributes files. Furthermore it collects and expands macro
	* expressions. The method {@link #getAttributes()} yields the ready processed
	* attributes for the current path represented by the {@link TreeWalk}
	* <p>
	* The implementation is based on the specifications in
	* http://git-scm.com/docs/gitattributes
	*
	* @since 4.3
	*/
	public class AttributesHandler {
	private static final String MACRO_PREFIX = "[attr]"; //$NON-NLS-1$

	private static final String BINARY_RULE_KEY = "binary"; //$NON-NLS-1$

	/**
	* This is the default <b>binary</b> rule that is present in any git folder
	* <code>[attr]binary -diff -merge -text</code>
	*/
	private static final List<Attribute> BINARY_RULE_ATTRIBUTES = new AttributesRule(
	MACRO_PREFIX + BINARY_RULE_KEY, "-diff -merge -text") //$NON-NLS-1$
	.getAttributes();

	private final TreeWalk treeWalk;

	private final AttributesNode globalNode;

	private final AttributesNode infoNode;

	private final Map<String, List<Attribute>> expansions = new HashMap<>();

	/**
	* Create an {@link AttributesHandler} with default rules as well as merged
	* rules from global, info and worktree root attributes
	*
	* @param treeWalk
	* @throws IOException
	*/
	public AttributesHandler(TreeWalk treeWalk) throws IOException {
	this.treeWalk = treeWalk;
	AttributesNodeProvider attributesNodeProvider =treeWalk.getAttributesNodeProvider();
	this.globalNode = attributesNodeProvider != null
	? attributesNodeProvider.getGlobalAttributesNode() : null;
	this.infoNode = attributesNodeProvider != null
	? attributesNodeProvider.getInfoAttributesNode() : null;

	AttributesNode rootNode = attributesNode(treeWalk,
	rootOf(
	treeWalk.getTree(WorkingTreeIterator.class)),
	rootOf(
	treeWalk.getTree(DirCacheIterator.class)),
	rootOf(treeWalk
	.getTree(CanonicalTreeParser.class)));

	expansions.put(BINARY_RULE_KEY, BINARY_RULE_ATTRIBUTES);
	for (AttributesNode node : new AttributesNode[] { globalNode, rootNode,
	infoNode }) {
	if (node == null) {
	continue;
	}
	for (AttributesRule rule : node.getRules()) {
	if (rule.getPattern().startsWith(MACRO_PREFIX)) {
	expansions.put(rule.getPattern()
	.substring(MACRO_PREFIX.length()).trim(),
	rule.getAttributes());
	}
	}
	}
	}

	/**
	* see {@link TreeWalk#getAttributes()}
	*
	* @return the {@link Attributes} for the current path represented by the
	* {@link TreeWalk}
	* @throws IOException
	*/
	public Attributes getAttributes() throws IOException {
	String entryPath = treeWalk.getPathString();
	boolean isDirectory = (treeWalk.getFileMode() == FileMode.TREE);
	Attributes attributes = new Attributes();

	// Gets the info attributes
	mergeInfoAttributes(entryPath, isDirectory, attributes);

	// Gets the attributes located on the current entry path
	mergePerDirectoryEntryAttributes(entryPath, entryPath.lastIndexOf('/'),
	isDirectory,
	treeWalk.getTree(WorkingTreeIterator.class),
	treeWalk.getTree(DirCacheIterator.class),
	treeWalk.getTree(CanonicalTreeParser.class),
	attributes);

	// Gets the attributes located in the global attribute file
	mergeGlobalAttributes(entryPath, isDirectory, attributes);

	// now after all attributes are collected - in the correct hierarchy
	// order - remove all unspecified entries (the ! marker)
	for (Attribute a : attributes.getAll()) {
	if (a.getState() == State.UNSPECIFIED)
	attributes.remove(a.getKey());
	}

	return attributes;
	}

	/**
	* Merges the matching GLOBAL attributes for an entry path.
	*
	* @param entryPath
	* the path to test. The path must be relative to this attribute
	* node's own repository path, and in repository path format
	* (uses '/' and not '\').
	* @param isDirectory
	* true if the target item is a directory.
	* @param result
	* that will hold the attributes matching this entry path. This
	* method will NOT override any existing entry in attributes.
	*/
	private void mergeGlobalAttributes(String entryPath, boolean isDirectory,
	Attributes result) {
	mergeAttributes(globalNode, entryPath, isDirectory, result);
	}

	/**
	* Merges the matching INFO attributes for an entry path.
	*
	* @param entryPath
	* the path to test. The path must be relative to this attribute
	* node's own repository path, and in repository path format
	* (uses '/' and not '\').
	* @param isDirectory
	* true if the target item is a directory.
	* @param result
	* that will hold the attributes matching this entry path. This
	* method will NOT override any existing entry in attributes.
	*/
	private void mergeInfoAttributes(String entryPath, boolean isDirectory,
	Attributes result) {
	mergeAttributes(infoNode, entryPath, isDirectory, result);
	}

	/**
	* Merges the matching working directory attributes for an entry path.
	*
	* @param entryPath
	* the path to test. The path must be relative to this attribute
	* node's own repository path, and in repository path format
	* (uses '/' and not '\').
	* @param nameRoot
	* index of the '/' preceeding the current level, or -1 if none
	* @param isDirectory
	* true if the target item is a directory.
	* @param workingTreeIterator
	* @param dirCacheIterator
	* @param otherTree
	* @param result
	* that will hold the attributes matching this entry path. This
	* method will NOT override any existing entry in attributes.
	* @throws IOException
	*/
	private void mergePerDirectoryEntryAttributes(String entryPath,
	int nameRoot, boolean isDirectory,
	@Nullable WorkingTreeIterator workingTreeIterator,
	@Nullable DirCacheIterator dirCacheIterator,
	@Nullable CanonicalTreeParser otherTree, Attributes result)
	throws IOException {
	// Prevents infinite recurrence
	if (workingTreeIterator != null \|\| dirCacheIterator != null
	\|\| otherTree != null) {
	AttributesNode attributesNode = attributesNode(
	treeWalk, workingTreeIterator, dirCacheIterator, otherTree);
	if (attributesNode != null) {
	mergeAttributes(attributesNode,
	entryPath.substring(nameRoot + 1), isDirectory,
	result);
	}
	mergePerDirectoryEntryAttributes(entryPath,
	entryPath.lastIndexOf('/', nameRoot - 1), isDirectory,
	parentOf(workingTreeIterator), parentOf(dirCacheIterator),
	parentOf(otherTree), result);
	}
	}

	/**
	* Merges the matching node attributes for an entry path.
	*
	* @param node
	* the node to scan for matches to entryPath
	* @param entryPath
	* the path to test. The path must be relative to this attribute
	* node's own repository path, and in repository path format
	* (uses '/' and not '\').
	* @param isDirectory
	* true if the target item is a directory.
	* @param result
	* that will hold the attributes matching this entry path. This
	* method will NOT override any existing entry in attributes.
	*/
	protected void mergeAttributes(@Nullable AttributesNode node,
	String entryPath,
	boolean isDirectory, Attributes result) {
	if (node == null)
	return;
	List<AttributesRule> rules = node.getRules();
	// Parse rules in the reverse order that they were read since the last
	// entry should be used
	ListIterator<AttributesRule> ruleIterator = rules
	.listIterator(rules.size());
	while (ruleIterator.hasPrevious()) {
	AttributesRule rule = ruleIterator.previous();
	if (rule.isMatch(entryPath, isDirectory)) {
	ListIterator<Attribute> attributeIte = rule.getAttributes()
	.listIterator(rule.getAttributes().size());
	// Parses the attributes in the reverse order that they were
	// read since the last entry should be used
	while (attributeIte.hasPrevious()) {
	expandMacro(attributeIte.previous(), result);
	}
	}
	}
	}

	/**
	* @param attr
	* @param result
	* contains the (recursive) expanded and merged macro attributes
	* including the attribute iself
	*/
	protected void expandMacro(Attribute attr, Attributes result) {
	// loop detection = exists check
	if (result.containsKey(attr.getKey()))
	return;

	// also add macro to result set, same does native git
	result.put(attr);

	List<Attribute> expansion = expansions.get(attr.getKey());
	if (expansion == null) {
	return;
	}
	switch (attr.getState()) {
	case UNSET: {
	for (Attribute e : expansion) {
	switch (e.getState()) {
	case SET:
	expandMacro(new Attribute(e.getKey(), State.UNSET), result);
	break;
	case UNSET:
	expandMacro(new Attribute(e.getKey(), State.SET), result);
	break;
	case UNSPECIFIED:
	expandMacro(new Attribute(e.getKey(), State.UNSPECIFIED),
	result);
	break;
	case CUSTOM:
	default:
	expandMacro(e, result);
	}
	}
	break;
	}
	case CUSTOM: {
	for (Attribute e : expansion) {
	switch (e.getState()) {
	case SET:
	case UNSET:
	case UNSPECIFIED:
	expandMacro(e, result);
	break;
	case CUSTOM:
	default:
	expandMacro(new Attribute(e.getKey(), attr.getValue()),
	result);
	}
	}
	break;
	}
	case UNSPECIFIED: {
	for (Attribute e : expansion) {
	expandMacro(new Attribute(e.getKey(), State.UNSPECIFIED),
	result);
	}
	break;
	}
	case SET:
	default:
	for (Attribute e : expansion) {
	expandMacro(e, result);
	}
	break;
	}
	}

	/**
	* Get the {@link AttributesNode} for the current entry.
	* <p>
	* This method implements the fallback mechanism between the index and the
	* working tree depending on the operation type
	* </p>
	*
	* @param treeWalk
	* @param workingTreeIterator
	* @param dirCacheIterator
	* @param otherTree
	* @return a {@link AttributesNode} of the current entry,
	* {@link NullPointerException} otherwise.
	* @throws IOException
	* It raises an {@link IOException} if a problem appears while
	* parsing one on the attributes file.
	*/
	private static AttributesNode attributesNode(TreeWalk treeWalk,
	@Nullable WorkingTreeIterator workingTreeIterator,
	@Nullable DirCacheIterator dirCacheIterator,
	@Nullable CanonicalTreeParser otherTree) throws IOException {
	AttributesNode attributesNode = null;
	switch (treeWalk.getOperationType()) {
	case CHECKIN_OP:
	if (workingTreeIterator != null) {
	attributesNode = workingTreeIterator.getEntryAttributesNode();
	}
	if (attributesNode == null && dirCacheIterator != null) {
	attributesNode = dirCacheIterator
	.getEntryAttributesNode(treeWalk.getObjectReader());
	}
	if (attributesNode == null && otherTree != null) {
	attributesNode = otherTree
	.getEntryAttributesNode(treeWalk.getObjectReader());
	}
	break;
	case CHECKOUT_OP:
	if (otherTree != null) {
	attributesNode = otherTree
	.getEntryAttributesNode(treeWalk.getObjectReader());
	}
	if (attributesNode == null && dirCacheIterator != null) {
	attributesNode = dirCacheIterator
	.getEntryAttributesNode(treeWalk.getObjectReader());
	}
	if (attributesNode == null && workingTreeIterator != null) {
	attributesNode = workingTreeIterator.getEntryAttributesNode();
	}
	break;
	default:
	throw new IllegalStateException(
	"The only supported operation types are:" //$NON-NLS-1$
	+ OperationType.CHECKIN_OP + "," //$NON-NLS-1$
	+ OperationType.CHECKOUT_OP);
	}

	return attributesNode;
	}

	private static <T extends AbstractTreeIterator> T parentOf(@Nullable T node) {
	if(node==null) return null;
	@SuppressWarnings("unchecked")
	Class<T> type = (Class<T>) node.getClass();
	AbstractTreeIterator parent = node.parent;
	if (type.isInstance(parent)) {
	return type.cast(parent);
	}
	return null;
	}

	private static <T extends AbstractTreeIterator> T rootOf(
	@Nullable T node) {
	if(node==null) return null;
	AbstractTreeIterator t=node;
	while (t!= null && t.parent != null) {
	t= t.parent;
	}
	@SuppressWarnings("unchecked")
	Class<T> type = (Class<T>) node.getClass();
	if (type.isInstance(t)) {
	return type.cast(t);
	}
	return null;
	}

	}