Instead of polling the system clock on every update(1) method call,
use a scheduled executor to toggle a volatile once per second until
the task is done.  Check the volatile on each update(int), looking
to see if output should occur.

This limits progress output to either once per 1% complete, or once
per second.  To save time during update calls the timer isn't reset
during each 1% of output, which means we may see one unnecessary
output trigger if at least 1% completed during the one second of the
alarm time.

Change-Id: I8fdd7e31c37bef39a5d1b3da7105da0ef879eb84
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

The diff algorithm which is used by Merge, Cherry-Pick, Rebase
should be configurable. A new configuration parameter "diff.algorithm"
is introduced which currently accepts the values "myers" or
"histogram". Based on this parameter for example the ResolveMerger
will choose a diff algorithm. The reason for this is bug 331078.
This bug shows that JGit is more compatible with C Git when
histogram diff is in place. But since histogram diff is quite new we
need an easy way to fall back to Myers diff.

Bug: 331078
Change-Id: I2549c992e478d991c61c9508ad826d1a9e539ae3
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
Signed-off-by: Philipp Thun <philipp.thun@sap.com>

jgit.sh <command> --help was not working for the commands Diff
and ShowCommands because of missing metaVar information. Missing
information is added here.

Change-Id: I0ab7e35006b6aa7d4326a634309dddfcdb78f2a6
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>

The diff command in the pgm package was enhanced to allow
choosing the diff algorithm (currently myers or histogram)

Change-Id: I72083e78fb5c92868eb5d8ec512277d212a39349
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>

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>

Similar to C Git, default our difference when no trees are given
to us to something that makes a tiny bit of sense to the human.

We also now support the --cached flag, and have its meaning work the
same way as C Git.

Change-Id: I2f19dad4e018404e280ea3e95ebd448a4b667f59
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Change-Id: I0c7154a51143d56362f12ee4fa93133778d3a9eb
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Applications just want a quick way to configure our diff
implementation, and then just want to use it without a lot of fuss.

Move all of the rename detection logic and path following logic
out of our pgm package and into DiffFormatter itself, making it
much easier for a GUI to take advantage of the features without
duplicating a lot of code.

Change-Id: I4b54e987bb6dc804fb270cbc495fe4cae26c7b0e
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Change-Id: If92545b731ff80bff071aee9bbd852bbd187c7c5
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

TreeWalk calls this value "path", while "name" is the stuff after the
last slash.  FileHeader should do the same thing to be consistent.
Rename getOldName to getOldPath and getNewName to getNewPath.

Bug: 318526
Change-Id: Ib2e372ad4426402d37939b48d8f233154cc637da
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Similar to what we did with diff, implement whitespace ignore options
for log too.  This requires us to define some means of creating any
RawText object type at will inside of DiffFormatter, so we define a
new factory interface to construct RawText instances on demand.

Unfortunately we have to copy the entire block of common options.
args4j only processes the options/arguments on the one command class
and Java doesn't support multiple inheritance.

Change-Id: Ia16cd3a11b850fffae9fbe7b721d7e43f1d0e8a5
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Passing around the OutputStream and the Repository is crazy.  Instead
put the stream in the constructor, since this formatter exists only to
output to the stream, and put the repository as a member variable that
can be optionally set.

Change-Id: I2bad012fee7f40dc1346700ebd19f1e048982878
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Implement rename detection in the command line diff and log commands.
Also support --name-status, -p and -U flags, as these can be quite
useful to view more detail.

All of the Git patch file formatting code is now moved over to the
DiffFormatter class.  This permits us to reuse it in any context,
including inside of IDEs.

Change-Id: I687ccba34e18105a07e0a439d2181c323209d96c
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Added a check in Diff to ensure that files that are most likely
not text are not line-by-line diffed. Files are determined to be
binary by checking the first 8000 bytes for a null character. This
is a similar heuristic to what C Git uses.

Change-Id: I2b6f05674c88d89b3f549a5db483f850f7f46c26

Added code to support ignoring leading, trailing, and changed
whitespace when performing a diff operation. I also added command
line options to Diff to enable the various whitespace ignoring
methods. These match the flags for git diff.

Change-Id: Ie56301aafad59ee3f0fe5de62719f5023cd702c8

We drop the "Object" suffix, because its pretty clear here that
we want to open an object, given that we pass in AnyObjectId as
the main parameter.  We also fix the calling convention to throw
a MissingObjectException or IncorrectObjectTypeException, so that
callers don't have to do this error checking themselves.

Change-Id: I72c43353cea8372278b032f5086d52082c1eee39
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>

My Galileo eclipse was complaining about unneeded import statements and
how static methods have been accessed in Diff.java. There was also one method
call which could be removed because he had no sideeffects and the return value
was not used. I fixed this so that there are no warnings anymore.

Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
Change-Id: I48d7e01536aab1524140d72af574e3fd7149cd23

This commit contains fixes provided by Christian Halstrick.

Bug: 291083
Eclipse-CQ: 3559
Change-Id: If8d187e70a51f31040f99098489e513791dc6415
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Per CQ 3448 this is the initial contribution of the JGit project
to eclipse.org.  It is derived from the historical JGit repository
at commit 3a2dd9921c.

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