Test was broken by commit b087bba3 changing formatting of merge
commit messages.

Change-Id: I98b1b936b9b6cbaa50fbc59d243a43e66a6ee9f9
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

We stopped handling URIs such as "example.com:/some/p ath", because
this was confused with the Windows absolute path syntax of "c:/path".
Support absolute style scp URIs again, but only when the host name
is more than 2 characters long.

Change-Id: I9ab049bc9aad2d8d42a78c7ab34fa317a28efc1a
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

IndexDiff was extended to detect files which are both removed from the
index and untracked.  Before this change these files were only added
to the removed collection.

Change-Id: I971d8261d2e8932039fce462b59c12e143f79f90
Signed-off-by: Jens Baumgart <jens.baumgart@sap.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

There was a bug in ResolveMerger which is one reason for
bug 328841. If a merge was failing because of conflicts
deletions where not handled correctly. Files which have
to be deleted (because there was a non-conflicting deletion
coming in from THEIRS) are not deleted. In the
non-conflicting case we also forgot to delete the file but
in this case we explicitly checkout in the end these files
get deleted during that checkout.

This is fixed by handling incoming deletions explicitly.

Bug: 328841
Change-Id: I7f4c94ab54138e1b2f3fcdf34fb803d68e209ad0
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>

The automatically generated commit message of a merge should have the
same structure as in C Git for consistency (as per git fmt-merge-msg).

Before this change:

  merging refs/heads/a into refs/heads/master

After:

  Merge branch 'a'

Plurals, "into" and joining by "," and "and" also work.

Change-Id: I9658ce2817adc90d2df1060e8ac508d7bd0571cb

There were also some compiler warning due to empty catch blocks that
were fixed.

Change-Id: I165bcddcdfacd34f020d1b938a41954916eb106e
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>

This mirrors the getByte() API in ObjectId and allows the caller to
modify a single byte, which is useful when updating it as part of a
loop walking through 0x00..0xff inside of a range of objects.

Change-Id: I57fa8420011fe5ed5fc6bfeb26f87a02b3197dab
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Processing git notes requires random access to part of the raw data
of each ObjectId... which isn't easy because ObjectIds are stored
with an internal representation of 5 ints.  Expose random access
to the individual data bytes through new methods, avoiding the
need to convert first to a byte[20].

Change-Id: I99e64700b27fc0c95aa14ef8ad46a0e8832d4441
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

The JGit merge algorithm or the Merge Command may have problems with handling
deletions always correctly. Therefore one additional test is added to check
this.

Change-Id: Id6aa49136996b29047c340994fe7faba68858e8c
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>

JGit merge algorithm behaved differently from C Git when
we had adjacent modifications. If line 9 was modified by
OURS and line 10 by theirs then C Git will return a
conflict while JGit was seeing this as independent
modifications. This change is not only there to achieve
compatibility, but there where also some really wrong
merge results produced by JGit in the area of adjacent
modifications.

Change-Id: I8d77cb59e82638214e45b3cf9ce3a1f1e9b35c70
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>

Introduced similar helper methods than in AbstractDiffTestCase.
Then the test cases are much smaller and better understandable.

Change-Id: I2beb4db5a93bd8c0c1238d5d3039cbd6719eee90
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>

When adding a new method near the end of the sequence we want to
show the full method inserted, and not tear the prior method due
to the common trailing curly brace being consumed as part of the
common end region of the sequences.

Bug: 328895
Change-Id: I233bc40445fb5452863f5fb082bc3097433a8da6
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

This test isn't that useful.  The better way to evaluate diff
algorithm performance is to run `jgit debug-diff-algorithms` over
real-world repositories, such as linux-2.6.git.  Whenever we modify
an algorithm we should manually verify that its runtime performance
doesn't get any worse than it already is.

Change-Id: I0beed3a5a8a537c958a5a6438a1283f97fa2097a
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

HistogramDiff failed on cases where the initial element for the LCS
was actually very common (e.g. has 20 occurrences), and the first
element of the inserted region after the LCS was also common but
had fewer occurrences (e.g. 10), while the LCS also contained a
unique element (1 occurrence).

This happens often in Java source code.  The initial element for
the LCS might be the empty line ("\n"), and the inserted but common
element might be "\t/**\n", with the LCS being a large span of
lines that contains unique method declarations.  Even though "/**"
occurs less often than the empty line its not a better LCS if the
LCS we already have contains a unique element.

The logic in HistogramDiff would normally have worked fine, except I
tried to optimize scanning of B by making tryLongestCommonSequence
return the end of the region when there are matching elements
found in A.  This allows us to skip over the current LCS region,
as it has already been examined, but caused us to fail to identify
an element that had a lower occurrence count within the region.

The solution used here is to trade space-for-time by keeping a
table of A positions to their occurrence counts.  This allows the
matching logic to always use the smallest count for this region,
even if the smallest count doesn't appear on the initial element.

The new unit test testEdit_LcsContainsUnique() verifies this new
behavior works as expected.

Bug: 328895
Change-Id: Id170783b891f645b6a8cf6f133c6682b8de40aaf
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

As described in Bug 328551 there was a bug that the merge algorithm
was not always reporting conflicts when the same line was deleted
and modified. This problem was introduced during commit
0c017188b4 when reported conflicts have
been checked for common pre- and suffixes.

This was fixed here by better determining whether after stripping
off common prefixes and suffixes from a conflicting region there
is still some conflicting part left.
I also added a unit test to test this situation.

Bug: 328551
Change-Id: Iec6c9055d00e5049938484a27ab98dda2577afc4
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>

When creating a local branch based on another local branch, the
upstream configuration contains "." as origin and the source branch
as "merge". The PullCommand should support this by skipping the
fetch step altogether and use the base branch to merge with.

Change-Id: I260a1771aeeffca5b0161d1494fd63c672ecc2a6
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>

Don't permit transient worker threads to access the underlying output
stream of a ProgressMonitor, as they might get marked as the stream's
writer thread.  Instead proxy update events from the workers back onto
the application's real work thread.  This ensures that the stream only
sees a single thread, and its the thread that will remain alive for
the entire life cycle of the operation.

This fixes IOException("Write end dead") during local repository fetch
when threaded delta search is enabled.  One of the transient delta
search threads became the designated writer for the pipe, and when it
terminated the reader end thought the writer was dead, even though the
main writer thread was still executing in PackWriter.

Bug: 326557
Change-Id: I01d1b20a3d7be1c0b480c7fb5c9773c161fe5c15
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Implemented the initial version of a cherry-pick command.
A correct error handling is missing (what happens if the
checkout fails, the cherry-pick leads to conflicts etc).
But straightforward cherry-picks works.

Change-Id: I235c0eb3a7a2d5bdfe40400f1deed06f29d746e1
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Since the introduction of HashedSequence we no longer need to supply
the RawTextComparator at the time of constructing a RawText.  Drop the
definition from the constructor, because it doesn't make sense as part
of our public API.

Change-Id: Iaab34611d60eee4a2036830142b089b2dae81842
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

When an empty line was inserted at the beginning of the common end
part of a RawText the comparator incorrectly considered it to be
common, which meant the DiffAlgorithm would later not even have it be
part of the region it examines.  This would cause JGit to skip a line
of insertion, which later confused Gerrit Code Review when it tried to
match up the pre and post RawText files for a difference that had this
type of insertion.

Define two new unit tests to check for this insertion of a blank line
condition and correct for it by removing the LF from the common region
when the condition is detected.

Change-Id: I2108570eb2929803b9a56f9fb9c400c758e7156b
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Change-Id: I003b601f384ff1213da6750dd13846367a511d0b
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

It wrongly uses the full name of the branch to remove the
configuration entries but must use the shortened one.

Change-Id: Ie386a128a6c6beccc20bafd15c2e36254c5f560d
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>

When creating a branch with CreateBranchCommand.call() without
specifying an explicit startPoint HEAD should be used as startPoint.
There was a bug leading to an NPE in such a case.

Change-Id: Ic0a5dc1f33a0987d66c09996c8012c45785500ff
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>

We wanted to wrap all LowLevel JGit excpetions into a
JGitInternalException so that users of this high-level interface
don't have to explicitly catch all of them. This
was forgotten on BranchCreateCommand.call() and I added
it.

Change-Id: Ie140e99574fb004137c66e80fb92eb6c6d0fa5e1
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>

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>

The need for branching becomes more pressing with pull
support: we need to make sure the upstream configuration entries
are written correctly when creating and renaming branches
(and of course are cleaned up when deleting them).
This adds support for listing, adding, deleting and renaming
branches including the more common options.

Bug: 326938
Change-Id: I00bcc19476e835d6fd78fd188acde64946c1505c
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>

Application code, including unit tests for storage implementations,
should not extend RevCommit outside of the scope of using it for a
RevWalk.  Its a lot of overhead and unlikely to work long-term.

Instead for the one test that matters, use a custom subclass of the
ObjectId type.  This lets us measure exactly what we are looking for,
which is that the subclass isn't retained.

A lot of other tests were unnecessarily wrapping an object with a
RevCommit and storing that back into the RefUpdate.  This is just
retesting what the earlier no-cache test was doing, and complicated
the test considerably.  Drop that code and just rely on the value that
was configured by the helper method.

Change-Id: I5b31813484eaa306e9bc4de9622dd5bd4846b16d
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

In bug 323571 it is mentioned that if you call
'toURI().toURL().toString()' on a java.io.File you cannot pass
that string to jgit as an URIish. Problem is that the passed
URI looks like 'file:/C:/a/b.txt' and that we where expecting
double slashes after scheme':'. This fix adds support for this
single-slash file URLs.

Bug: 323571
Change-Id: I866a76a4fcd0c3b58e0d26a104fc4564e7ba5999
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>

This is the minimal implementation of a "Pull" command. It does not
have any parameters besides the generic progress monitor and timeout.
It works on the currently checked-out branch and assumes that the
configuration contains the keys "branch.<branch name>.remote" and
"branch.<branch name>.merge" to determine the remote configuration
for the fetch and the remote branch name for the merge.

Bug: 303404
Change-Id: I7fe09029996d0cfc09a7d8f097b5d6af1488fa93
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>

There where quite some bugs regarding wrong URI parsing. In order
to solve them the parsing has to be refactored. We now have
specialized regexps for 'scheme://host/...', scp URIs and local
file names. Now we can detect problems while parsing 'git://host:/abc' which
was previously not possible.

Bug: 315571
Bug: 292897
Bug: 307017
Bug: 323571
Bug: 317388
Change-Id: If72576576ebb6b9d9dc8b7e51ddd87c9909e8b62
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

The regular expression which should handle the
user/password part in an URI was potentially
processing too many chars. This led to problems
when user/pwd and port was specified

Change-Id: I87db02494c4b367283e1d00437b1c06d2c8fdd28
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

URIs for the git protocol have to have a hostname.
(see http://www.kernel.org/pub/software/scm/git/docs
/git-clone.html#_git_urls_a_id_urls_a) Some tests tested
URIs like git:/abc.git which is not allowed. Fixed this.

Change-Id: Ia3b8b681ad6592f03b090a874a6e91068a8301fe
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>

Change-Id: Iff144a51fdc9a1112a21492c390a873a2b293bc9
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>

Projects like org.eclipse.mdt contain large XML files about 6 MiB
in size.  So does the Android project platform/frameworks/base.
Doing a clone of either project with JGit takes forever to checkout
the files into the working directory, because delta decompression
tends to be very expensive as we need to constantly reposition the
base stream for each copy instruction.  This can be made worse by
a very bad ordering of offsets, possibly due to an XML editor that
doesn't preserve the order of elements in the file very well.

Increasing the threshold to the same limit PackWriter uses when
doing delta compression (50 MiB) permits a default configured
JGit to decompress these XML file objects using the faster
random-access arrays, rather than re-seeking through an inflate
stream, significantly reducing checkout time after a clone.

Since this new limit may be dangerously close to the JVM maximum
heap size, every allocation attempt is now wrapped in a try/catch
so that JGit can degrade by switching to the large object stream
mode when the allocation is refused.  It will run slower, but the
operation will still complete.

The large stream mode will run very well for big objects that aren't
delta compressed, and is acceptable for delta compressed objects that
are using only forward referencing copy instructions.  Copies using
prior offsets are still going to be horrible, and there is nothing
we can do about it except increase core.streamFileThreshold.

We might in the future want to consider changing the way the delta
generators work in JGit and native C Git to avoid prior offsets once
an object reaches a certain size, even if that causes the delta
instruction stream to be slightly larger.  Unfortunately native
C Git won't want to do that until its also able to stream objects
rather than malloc them as contiguous blocks.

Change-Id: Ief7a3896afce15073e80d3691bed90c6a3897307
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>

HistogramDiff is an alternative implementation of patience diff,
performing a search over all matching locations and picking the
longest common subsequence that has the lowest occurrence count.
If there are unique common elements, its behavior is identical to
that of patience diff.

Actual performance on real-world source files usually beats
MyersDiff, sometimes by a factor of 3, especially for complex
comparators that ignore whitespace.

Change-Id: I1806cd708087e36d144fb824a0e5ab7cdd579d73
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Each algorithm should produce a particular number of results
given one of the standard inputs used during the performance
tests.  To help ensure those tests are accurate, assert that
the edit list length is correct.

Change-Id: I292f8fde0cec6a60a75ce09e70814a00ca47cb99
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Because PatienceDiff works by looking for common unique lines within
the region, the DiffTestDataGenerator needs to be modified to produce
a unique character for each region.  If we don't give PatienceDiff
a few unique points, it will just offer back a single REPLACE edit
that covers the entire files, and this doesn't tell us very much.

Change-Id: I5129faea1e763c74739118ca20d86bd62e0deaef
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

For certain tiny input sequences, every DiffAlgorithm should produce
exactly the same results, as there should be no ambiguity.  Package
these up in an abstract TestCase that algorithms can extend from in
order to perform basic validation of their implementation.

Since these tests are more complete than what we used to have for
the MyersDiff algorithm, throw away Johannes' tests and only use
this new package.

Change-Id: I9a044330887c849ad4c78aa5c7aa04c783c10252
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Change-Id: Ic7a76df2861ea6c569ab9756a62018987912bd13
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

This is a faster exact match based form that tries to improve
performance for the common case of the header and trailer of
a text file not changing at all. After this fast path we use
the slower path based on the super class' using equals() to
allow for whitespace ignore modes to still work.

Some simple performance testing showed a major improvement over the
older implementation for a common edit we see in JGit.  The test
compared blob 29a89bc and 372a978, which is the ObjectDirectory.java
file difference in commit 41dd9ed1c0.
The two text files are approximately 22 KiB in size.

  DEFAULT        old   203900 ns
  DEFAULT        new   100400 ns

This new version is 2x faster for the DEFAULT comparator, which does
not treat space specially.  This is because we can now examine a
larger swath of text with fewer instructions per byte compared.  The
older algorithm had to stop at each line break and recompute how to
examine the next line, while the new algorithm only stops when the
first difference is found.

  WS_IGNORE_ALL  old   298500 ns
  WS_IGNORE_ALL  new    63300 ns

Its 4.7x faster for the whitespace ignore comparator, as the common
header and footer do not have a whitespace difference.  Avoiding the
special case handling for whitespace on each byte considered saves a
lot of time.

Since most edits to source code (and other text like files) appears in
the interior of the file, fast elimination of common header/footer
means faster diff throughput.  In the less common case of an actual
header or footer edit, the common header/footer elimination is stopped
rather quickly either way, so there is very little downside to the
optimiation applied here.

Change-Id: I1d501b4c3ff80ed086b20bf12faf51ae62167db7
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Adds API for performing git fetch operations.

Change-Id: Idd95664fd4e3bca03211e4ffda3e354849f92a35
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>

Method test006_readCaseInsensitive in TestConfig already does the
same thing, and doesn't require an OS specific test for the value being 
asserted.
This is additionally a fast fix for the failing JUnit test after 
change 3fe5276. 

Change-Id: I96d2794dbc7db55bdd0fbfcf675aabb15cc8419f
Signed-off-by: Stefan Lay <stefan.lay@sap.com>

Change-Id: I54815c85b32b9492c059064b39f48677e68c5e90
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Change-Id: Ideab4923a5d8055f0e8a36ddcf0bc8adbf71c329
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Change-Id: I114106f3286c36f7d5e136748a7e5130f4da163f
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Change-Id: I07a3391de03379f32ecfd055d45750e3860b2be4
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Change-Id: Ic411b1b8a7e6039ae3ff567e2c9cdd5db84f4d41
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

In PlotCommitList.enter() commits are positioned on lanes for visual
presentation. This implementation was buggy: commits without
children (often the starting points for the RevWalk) are not positioned
on separate lanes.

The problem was that when handling commits with multiple children
(that's where branches fork out) it was not handled that some of the
children may not have been positioned on a lane yet. I fixed that and
added a number of tests which specifically test the layout of commits
on lanes.

Bug: 300282
Bug: 320263
Change-Id: I267b97ecccb5251cec54cec90207e075ab50503e
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

This makes it easier to parametrize DiffFormatter with a different
implementation, as we later plan to add PatienceDiff to JGit.

Change-Id: Id35ef478d5fa20fe10a1ba297f9436fd7adde9ce
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

git allows remotes to be relative paths, but the regex
validating urls wouldn't accept anything starting with "..".
Other functionality works fine with these paths.

Bug: 311300
Change-Id: Ib74de0450a1c602b22884e19d994ce2f52634c77