To improve runtime performance, caching the WorkingTreeOptions inside
of the Config object using the Config.SectionParser API allows
the WorkingTreeOptions to be accessed more efficiently whenever a
FileTreeIterator is constructed for the Repository.

Instead of passing the filemode handling option into isModified(),
the WorkingTreeIterator should always honor whatever setting has
been configured in this repository, as defined by its own copy of
the WorkingTreeOptions.  This simplifies all of the callers as they
no longer need to lookup core.filemode on their own.

A few locations were changed from always using a hardcoded "true"
on the file mode to passing what is actually configured in the
repository.  This is a behavior change, but corrects what should be
considered to be bugs as the core.filemode variable wasn't always
being used.

Change-Id: Idb176736fa0dc97af372f1d652a94ecc72fb457c
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Some method parameters in WorkingTreeIterator are never used. Remove
them. Especially the removal of the FS parameter in isModified()
simplifies upcoming performance optimizations.

Change-Id: I7c449589283a4a6b6e23f2586cd784febdca8bcd
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>

Its confusing that a new TreeWalk() needs to have reset() invoked
on it before addTree().  This is a historical accident caused by
how TreeWalk was abused within ObjectWalk.

Drop the initial empty tree from the TreeWalk and thus remove a
number of pointless reset() operations from unit tests and some of
the internal JGit code.

Existing application code which is still calling reset() will simply
be incurring a few unnecessary field assignments, but they should
consider cleaning up their code in the future.

Change-Id: I434e94ffa43491019e7dff52ca420a4d2245f48b
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

java.io.File.delete() reports failure as an exceptional
return value false. Fix the code which silently ignored
this exceptional return value. Also remove some duplicate
deletion helper methods.

Change-Id: I80ed20ca1f07a2bc6e779957a4ad0c713789c5be
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

DirCacheCheckout needs to use ObjectLoader.copyTo to avoid loading the
complete content of a large file into the JVM heap.

Bug: 321097
Change-Id: I967590b6f233fd1c83d873075db01d653208b3b9
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
CC: Chris Aniszczyk <caniszczyk@gmail.com>
CC: Christian Halstrick <christian.halstrick@sap.com>

In the case where DirCacheCheckout was used to checkout a tree
without taking HEAD into account (e.g. during a clone or hard reset)
we didn't handle conflicts correctly. E.g. if there are conflicts
(entries with stage != 0) in the index and we tried to hard reset
we have been processing the conflicting pathes multiple times (once
for every stage). With this fix we will update the index with the
entry from the "merge" state (the state we want checkout) when we
detect existing conflicts.

Change-Id: Iffbddccaa588cf0d1460a5e44dabaf540d996e26
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>

When DirCacheCheckout should be used to checkout only one
tree (reset --hard, clone) then we had to use the standard
constructor and specify null as value for head. This change
adds explicit constructors not taking HEAD and documents
that.

Bug: 330021
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>

Added missing null check for getDirCacheEntry(). This method may
return null for example if the curernt entry is a subtree.

The code analyzer can't know that passing a value known to be null is
not a problem. Hence better pass null explicitly instead of the
parameters being null.

Change-Id: I8db6f8014de6c00dd95974d60f61ecc66191e6d4
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Change-Id: I950de82db15c4610dc5a94f304279971daef971e

When checking out a tree, files that are identical to the file in
the current index and working directory don't need to be updated.

Change-Id: I9e025a53facd42410796eae821baaeff684a25c5
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>

There was a chance that we hit a NPE which doing a checkout
with DirCacheCheckout when there is no HEAD (e.g. initial
checkout). This is fixed here.

Change-Id: Ie3b8cae21dcd90ba8352823ea94a700f8ee9221a
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>

Change-Id: I34d773b18e6a1ee05774d7b9471f9915c48aa63e
Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>

This adds the first merge strategy to JGit which does real
content-merges if necessary. The new merge strategy "resolve" takes as
input three commits: a common base, ours and theirs. It will simply takeover
changes on files which are only touched in ours or theirs. For files
touched in ours and theirs it will try to merge the two contents
knowing taking into account the specified common base.

Rename detection has not been introduced for now.

Change-Id: I49a5ebcdcf4f540f606092c0f1dc66c965dc66ba
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
Signed-off-by: Stefan Lay <stefan.lay@sap.com>

Implementation of a checkout (or 'git read-tree') operation which
works together with DirCache. This implementation does similar things
as WorkDirCheckout which main problem is that it works with deprecated
GitIndex. Since GitIndex doesn't support multiple stages of a file
which is required in merge situations this new implementation is
required to enable merge support.

Change-Id: I13f0f23ad60d98e5168118a7e7e7308e066ecf9c
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>