Local variables/parameters named 'db' and 'cmp' were hiding class
member variables of the same name.

Change-Id: I98b770587aaf73744a93e6a3ee33d131a9fa91e9
Signed-off-by: David Pursehouse <david.pursehouse@sonymobile.com>

Change-Id: I3e6f83ad2bc7d493e2c1ab5a8c60affa2b49c386
Signed-off-by: David Pursehouse <david.pursehouse@sonymobile.com>

org.eclipse.jgit.lib.Repository class is an example of the API which
should be written with Java 8 java.util.Optional<T> type. Unfortunately
this API is already released and widely used. The good clients are
currently doing their best with checking return values for null and bad
clients do not know how bad their code is.

I've tried not to change any logic and to be as less intrusive as
possible. Most of the JGit code was well prepared to this, only few
classes needed some smaller fixes.

This change fixes all compiler errors in JGit and replaces possible
NPE's with either appropriate exceptions, avoiding multiple "Nullable
return" method calls or early returning from the method.

Because annotating getDirectory() and getFS() as Nullable would cause
lot of additional changes in JGit and EGit they are postponed.

Change-Id: Ie8369d2c9c5fac5ce83b3b1b9bc217d7b55502a3
Signed-off-by: Andrey Loskutov <loskutov@gmx.de>

To prevent potential resource leaks.

Change-Id: I2039af04d9fb75405f8e13abf508623b7d4ef324
Signed-off-by: David Pursehouse <david.pursehouse@sonymobile.com>

See the discussion [1] in the Gerrit mailing list.

[1] https://groups.google.com/forum/#!topic/repo-discuss/RRQT_xCqz4o

Change-Id: I2c67384309c5c2e8511a7d0d4e088b4e95f819ff
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Also update help text for the merge command now supporting recursive
strategy as the default merge strategy.

Change-Id: I07886fe875c407e2244f562c003bb9d04f398026
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Translatable texts aren't API and shouldn't require maintenance of
@since tags to prevent API warnings.

Change-Id: I228ff37f17c0e792a6bc188c463a0d19138e88ac
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

A few classes such as Constanrs are marked with @SuppressWarnings, as are
toString() methods with many liternal, but otherwise $NLS-n$ is used for
string containing text that should not be translated. A few literals may
fall into the gray zone, but mostly I've tried to only tag the obvious
ones.

Change-Id: I22e50a77e2bf9e0b842a66bdf674e8fa1692f590

Invoke the wrapper types' valueOf via static imports.
For booleans used in asserts, add a new assert in
the JUnit utility package since out current version of JUnit
does not have the assert(boolean, boolean) method.

Change-Id: I9099bd8efbc8c133479344d51ce7dabed8958a2b

The underlying problem is that System.out is a PrintWriter and
as such it does not throw exceptions on error, but rather just
sets a flag and continues.

This changes replaces the use of System.out with a PrintWriter-like
writer that does not catch error, but instead throw them to the
caller.

Bug: 366243
Change-Id: I44405edc4416e943b87f09a0f6ed041c6c51b046

We have two constants with the same content. DOT_GIT is intended
for the git repository below the work tree, while DOT_GIT_EXT is
the ".git" directory extension usually associated with bare
repositories.

Change-Id: I0946b4beb2d1c3af289ddbbb5641d2f4e4c49d3f
Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>

DHT based repository types don't use a java.io.File to name the
repository.  Moving the type to a string starts to open up more types
of repository names, making the standard pgm package easier to reuse
on other storage systems.

Change-Id: I262ccc8c01cd6db88f832ef317b0e1e5db2d016a
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
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>

HistogramDiff outperforms it for any case where PatienceDiff needs to
fallback to another algorithm.  Consequently it's not worth keeping
around, because we would always want a fallback enabled.

Change-Id: I39b99cb1db4b3be74a764dd3d68cd4c9ecd91481
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

When working on a difference algorithm's implementation, its generally
more important to care about how it behaves on real-world inputs than
it does on fake inputs created for unit test cases.  Run each
implementation against a number of real-world repositories, looking at
changes between files in each commit.  This gives a better picture of
how a particular algorithm performs.

This test suite run against JGit and linux-2.6 with the current
available algorithms shows HistogramDiff always out-performs
MyersDiff, and by a wide margin on the linux-2.6 sources.  As
HistogramDiff has similar output properties as PatienceDiff, the
resulting edits are probably also more human-readable.  These test
results show that HistogramDiff is a good choice for the default
implementation, and also show that PatienceDiff isn't worth keeping.

  jgit: start at baa83ae
            2686 files,          760 commits
    N=         3 min lines,     3016 max lines
  Algorithm                     Time(ns) (  Time(ns) on   Time(ns) on )
                                         (          N=3        N=3016 )
  ---------------------------------------------------------------------
  histogram_myers              314652100 (         3900        298100 )
  histogram                    315973000 (         3800        302100 )
  patience                     774724900 (         4500        347900 )
  patience_histogram_myers     786332800 (         3700        351200 )
  myers                        819359300 (         4100        379100 )
  patience_myers               843416700 (         3800        348000 )

  linux-2.6.git: start at 85a3318
            4001 files,         2680 commits
    N=         2 min lines,    39098 max lines
  Algorithm                     Time(ns) (  Time(ns) on   Time(ns) on )
                                         (          N=2       N=39098 )
  ---------------------------------------------------------------------
  histogram_myers             1229870000 (         5900       2642700 )
  histogram                   1235654100 (         6000       2695400 )
  patience                    3856546000 (         5900       2627700 )
  patience_histogram_myers    3866728100 (         7000       2624000 )
  patience_myers              4004875300 (         8000       2651700 )
  myers                       9794679000 (         7200       2716200 )

Change-Id: I2502684d31f7851e720356820d04d8cf767f7229
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>