Bug: 431552
Change-Id: I469316f5645205016e1fa6b0fbd2ff3b509b14bc
Signed-off-by: Robin Stocker <robin@nibor.org>

Without explicit <p> elements, Javadoc joins all paragraph, resulting in
unreadable Javadoc output, e.g. see here:

http://download.eclipse.org/jgit/docs/jgit-2.1.0.201209190230-r/apidocs/org/eclipse/jgit/diff/MyersDiff.html

Also, <pre> is needed to preserve pre-formatted content.

The reflowing of text was automatically done on save.

Change-Id: Ia02dd6d759ae066700098e22669ef925e3c813b5

Use Integer, Character, and Long valueOf methods when
passing parameters to MessageFormat and other places
that expect objects instead of primitives

Change-Id: I5942fbdbca6a378136c00d951ce61167f2366ca4

Change-Id: I763590a45d75f00a09097ab6f89581a3bbd3c797

It's probably not possible that these numbers are negative in the
algorithm, but it's cleaner this way and gets rid of three more
FindBugs warnings.

Change-Id: Ifbce4e2c787fb9a7cd309c605e8d86211ef8a352

When passing to a fallback algorithm, we can avoid creating a new copy
of the hash codes for each sequence by passing in the hashed sequences
directly.  This makes it cheaper to switch from HistogramDiff down to
MyersDiff in a single pass.

Change-Id: Ibf2e81be57c083862eeb134279aed676653bf9b5
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

As it turns out, every single diff algorithm we might try to
implement can benfit from using the SequenceComparator's native
concept of the simple reduceCommonStartEnd() step.  For most inputs,
there can be a significant number of elements that can be removed
from the space the DiffAlgorithm needs to consider, which will
reduce the overall running time for the final solution.

Pool this logic inside of DiffAlgorithm itself as a default, but
permit a specific algorithm to override it when necessary.

Convert MyersDiff to use this reduction to reduce the space it
needs to search, making it perform slightly better on common inputs.

Change-Id: I14004d771117e4a4ab2a02cace8deaeda9814bc1
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Most diff implementations really want to use cached hash codes for
elements, rather than element equality, as they need to perform many
compares and unique hash codes for elements can really speed that
process up.

To make it easier to define element hash functions, move the caching
of hash codes into a wrapper sequence type, so that individual
sequence types like RawText don't need to do this themselves.  This
has a nice property of also allowing the sequence to no longer care
about the specific SequenceComparator that is going to be used, and
permits the caching to only examine the middle region that isn't
common to the two inputs.

Change-Id: If8623556da9419117b07c5073e8bce39de02570e
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

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>

Instead of making the sequence itself responsible for the equivalence
function, use an external function that is supplied by the caller.
This cleans up the code because we now say cmp.equals(a, ai, b, bi)
instead of a.equals(ai, b, bi).

This refactoring also removes the odd concept of creating different
types of sequences to have different behaviors for whitespace
ignoring.  Instead DiffComparator now supports singleton functions
that apply a particular equivalence algorithm to a type of sequence.

Change-Id: I559f494d81cdc6f06bfb4208f60780c0ae251df9
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

The strings are externalized into the root resource bundles.
The resource bundles are stored under the new "resources" source
folder to get proper maven build.

Strings from tests are, in general, not externalized. Only in
cases where it was necessary to make the test pass the strings
were externalized. This was typically necessary in cases where
e.getMessage() was used in assert and the exception message was
slightly changed due to reuse of the externalized strings.

Change-Id: Ic0f29c80b9a54fcec8320d8539a3e112852a1f7b
Signed-off-by: Sasa Zivkov <sasa.zivkov@sap.com>

This change only fixes warnings of the eclipse build regarding missing javadocs.
Some comments where just missing, so they have been added. Other comments where
at the wrong (from eclipse point of view) place, so eclipse was complaining.
Also two method which existed for debugging purposes have been removed to get
rid of Eclipse warngins about unused code.

MyersDiff was crashing with ArrayIndexOutOfBoundsException when
diffing huge files. This was because the snake data (begin and
end position while processing chunks of the text) was sequeezed
into a single int. But with longer texts to diff these values
exceeded the range of java int values. It is fixed by squeezing
the two ints into a long and by adding the LongList helper
class.

Change-Id: Iacb9082e1b076e994d1486aa8e512342ad7432b3
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>

Myers' algorithm is the standard way to generate diff scripts in
an efficient manner (especially memory-wise).

The source contains extensive documentation about the principal
ideas of the algorithm.

Bug: 291083
Eclipse-CQ: 3559
Change-Id: Id873e7c2c204692cb4a1a05d24b733154b9ed49c
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>