Commit Graph

599 Commits

Author SHA1 Message Date
Matthias Sohn ffc010fda4 [findbugs] Static comparator made final
Fixing FindBugs warning MS_SHOULD_BE_FINAL.

Change-Id: Ic69e6f6425e0a8950ce809eb3894f48a33e860aa
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2010-10-23 22:25:29 +02:00
Chris Aniszczyk 241ab22735 Add FindBugs and CPD to the build.
We need to use findbugs-maven-plugin:2.3.2-SNAPSHOT
since otherwise build fails with maven-3.0 [1], [2].
We should switch to the release version as soon
as this becomes available.

[1] http://www.sonatype.com/people/2010/10/maven-3-0-has-landed/
[2] http://jira.codehaus.org/browse/MFINDBUGS-122

Bug: 327799
Change-Id: I1c57f81cf6f0450e56411881488c4ee754e458e3
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2010-10-23 12:26:00 +02:00
Shawn O. Pearce d00420ae6e Make ObjectDirectory getPacks() work the first time
If an object hasn't been accessed yet the pack list for a repository
may not have been scanned from disk.  If an application (e.g. the dumb
transport servlet support code) asks for the pack list for an
ObjectDirectory, we should load it immediately.

Change-Id: I93d7b1bca422d905948e8e83b2afa83c8894a68b
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2010-10-20 00:51:44 +02:00
Shawn O. Pearce e51e06946f Update CachedObjectDirectory when inserting objects
If an ObjectInserter is created from a CachedObjectDirectory, we need
to ensure the cache is updated whenever a new loose object is actually
added to the loose objects directory, otherwise a future read from an
ObjectReader on the CachedObjectDirectory might not be able to open
the newly created object.

We mostly had the infrastructure in place to implement this due to the
injection of unpacked large deltas, but we didn't have a way to pass
the ObjectId from ObjectDirectoryInserter to CachedObjectDirectory,
because the inserter was using the underlying ObjectDirectory and not
the CachedObjectDirectory.  Redirecting to CachedObjectDirectory
ensures the cache is updated.

Change-Id: I1f7bdfacc7ad77ebdb885f655e549cc570652225
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-10-17 23:10:47 -07:00
Shawn O. Pearce f5e5b98c3a IndexPack: Make translated progress messages non-static
These messages may need to change depending on the current
thread's configured locale, and thus cannot be static.

Change-Id: I96751a63852ec9c4bf6c47edadcf8752700543df
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-10-17 22:21:38 -07:00
Christian Halstrick 609c6dc358 Fix possible NPE in DirCacheCheckout
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>
2010-10-18 00:19:13 +02:00
Christian Halstrick 9b4876cedf Add Cherry-Pick command
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>
2010-10-15 16:38:34 +02:00
Shawn O. Pearce 4c7e100910 Add getString utility functions to RawText
These routines can be useful when debugging, because we can add an
expression to the Eclipse "Expressions" panel to show the text that
appears on a line.  Gerrit Code Review also uses these in its own
subclass of RawText in order to format patch files, so pulling it up
to be part of core JGit may help other applications too.

Change-Id: I20a6b112e3403ecfc1c2715ae75dcecc1a85b167
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-10-13 20:50:44 -07:00
Shawn O. Pearce 3f3b6bfdb3 Remove dead RawText(RawTextComparator) constructor
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>
2010-10-13 20:48:51 -07:00
Shawn O. Pearce 8ea558bd82 Fix RawTextComparator reduceCommonStartEnd at empty lines
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>
2010-10-13 20:48:51 -07:00
Matthias Sohn f8eb7e16aa Generate correct version for jgit source bundle
The maven 2 build for jgit source bundle didn't create a correct
OSGi version string, instead of
    org.eclipse.jgit.source_0.10.0.<timestamp>
the generated OSGi version was
    org.eclipse.jgit.source_0.10.0.SNAPSHOT
This caused trouble when trying to install it from p2 repository.

Bug: 327616
Change-Id: Ic27c763ae9a4bcbb5bd6ed9562cd98bb4da3386b
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2010-10-13 15:33:46 +02:00
Christian Halstrick fb1e500adc Rename method to ResolveMerger.setWorkingTreeIterator()
renamed an ugly methodname

Change-Id: I26bda06ef64b8644fd3a555dc55dff43cdb56a71
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
2010-10-13 11:30:41 +02:00
Mathias Kinzler 5c135a5856 DeleteBranchCommand does not clean up upstream configuration
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>
2010-10-12 12:22:40 -07:00
Christian Halstrick 285d08d8b7 Fix NPE when calling CreateBranch without explict startpoint
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>
2010-10-12 19:18:53 +02:00
Christian Halstrick be93452842 Remove wrong comment in MergeCommand
There was a wrong javadoc comment telling that MergeCommand
only supports fast-forward merges. This has been fixed.

Change-Id: I7edea779a83528beee34a1753026288c384881ce
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
2010-10-12 19:18:51 +02:00
Christian Halstrick 0a8d54c286 Remove AmbiguousObjectException from BranchCreateCommand.call()
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>
2010-10-12 19:18:50 +02:00
Shawn O. Pearce e82cadc0dc Delete PatienceDiff
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>
2010-10-11 17:05:18 -05:00
Shawn O. Pearce 6048f34c58 Use HistogramDiff by default in DiffFormatter
Its behavior is similar to PatienceDiff, and runs nearly as fast,
often beating the performance of MyersDiff.

Change-Id: I43c3faefa8109f1a68ef57522bec9cf27b5df252
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-10-11 14:37:00 -07:00
Chris Aniszczyk 7429a9a5aa Merge "Define LowLevelDiffAlgorithm to bypass re-hashing" 2010-10-11 17:18:05 -04:00
Chris Aniszczyk 033ab7f6f0 Merge changes I50dcec81,Ieab28bb3
* changes:
  Fix empty block corner case in PatienceDiff
  Fix infinite loop in PatienceDiff
2010-10-11 15:00:51 -04:00
Shawn O. Pearce 4522b07d0f Fix corrupted large deltas
Large objects stored as deltas get unpacked by JGit into a loose
object, so they are cheaper to access later on.  This unpacking was
broken because TeeInputStream copied the wrong length into the loose
object, sometimes copying too many bytes into the result.  This
created a loose object that did not have the correct content, and
whose length did not match the length denoted in the object header.

Change-Id: I3ce1fd9f3dc5bd195249c7872b3bec49570424a2
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-10-10 18:50:46 -07:00
Shawn O. Pearce 1bd24a23f9 Define LowLevelDiffAlgorithm to bypass re-hashing
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>
2010-10-10 14:39:29 -07:00
Shawn O. Pearce 4fc50df97d Fix empty block corner case in PatienceDiff
There is a corner case where we get an EMPTY region during recursion,
but we didn't expect to receive that.  Its harmless to ignore the
region since the region is empty and has no content, so do so rather
than throwing an exception

Change-Id: I50dcec81ecba763072bb739adfab5879fb48b23a
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-10-10 14:39:29 -07:00
Shawn O. Pearce 7a0c126d5f Fix infinite loop in PatienceDiff
Certain inputs caused an infinite loop because the prior match data
couldn't be used as expected.  Rather than incrementing the match
pointer before looking at an element, do it after, so the loop breaks
when we wrap around to the starting point.

Change-Id: Ieab28bb3485a914eeddc68aa38c256f255dd778c
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-10-10 14:39:29 -07:00
Mathias Kinzler 7bdef4583b Add "Branch" command
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>
2010-10-10 15:38:49 -05:00
Christian Halstrick be2ddff6a7 Add support for single-slash URI
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>
2010-10-08 23:57:52 +02:00
Mathias Kinzler db55d13f5f Add "Pull" command
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>
2010-10-08 08:57:28 -05:00
Christian Halstrick 2160c09dd4 Refactored URI parsing to detect wrong URIs
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>
2010-10-08 11:12:09 +02:00
Christian Halstrick 2136095203 Fixed URI regexp regarding user/password part
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>
2010-10-08 11:08:12 +02:00
Christian Halstrick a1b0ca1807 Introduce commented constants for the segments of an URI regex
The regular expressions used to parse URI's are constructed by
concatenating different segments to a big String. Introduce
String constants for these segements and document them.

Change-Id: If8b9dbaaf57ca333ac0b6c9610c3d3a515c540f9
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
2010-10-08 06:44:16 +02:00
Matthias Sohn 784d388c49 Externalize strings in TransportHttp
Some strings were not externalized. Also use them in HTTP tests to
ensure that they will also succeed when message bundles are
translated.

Change-Id: Id02717176557e7d57e676e1339cd89f2be88d330
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2010-10-08 01:03:17 +03:00
Chris Aniszczyk 7a6efe1dfc Merge "Support HTTP basic and digest authentication" 2010-10-07 12:25:15 -04:00
Christian Halstrick 0a2b4c1455 Split URI regex strings differently
The strings used to construct the regex to parse
URIs are split differently. This makes it easier
to introduce meaningful String constants later on.

Change-Id: I9355fd42e57e0983204465c5d6fe5b6b93655074
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
2010-10-06 14:10:24 -05:00
Chris Aniszczyk 47e9e165b8 Add pull operation related constants
Change-Id: Idb7526800e80e17624ec05fb10bbc19e7f744f49
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
2010-10-06 11:46:13 -05:00
Chris Aniszczyk 98a41bd4d0 Add PushCommand API
Change-Id: Iff144a51fdc9a1112a21492c390a873a2b293bc9
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
2010-10-05 13:15:24 -05:00
Shawn O. Pearce 7ba31474a3 Increase core.streamFileThreshold default to 50 MiB
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>
2010-10-04 14:04:47 -05:00
Chris Aniszczyk 44b4f458a8 Merge "Add reflog message to TagCommand" 2010-09-29 10:09:43 -04:00
Shawn O. Pearce 858b2c92e8 Support HTTP basic and digest authentication
Natively support the HTTP basic and digest authentication methods
by setting the Authorization header without going through the JREs
java.net.Authenticator API.  The Authenticator API is difficult to
work with in a multi-threaded server environment, where its using
a singleton for the entire JVM.  Instead compute the Authorization
header from the URIish user and pass, if available.

Change-Id: Ibf83fea57cfb17964020d6aeb3363982be944f87
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2010-09-28 08:42:47 +02:00
Chris Aniszczyk e5c217bcf3 Merge "Use only a single instance for NLS translation bundles" 2010-09-27 17:59:36 -04:00
Chris Aniszczyk 153c796bce Merge "Update FetchCommand with dry run and thin options" 2010-09-27 10:07:49 -04:00
Robin Rosenberg 65ed25b34e Return the documented value from DirCacheCheckout.checkout
Change-Id: I34d773b18e6a1ee05774d7b9471f9915c48aa63e
Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
2010-09-27 10:51:07 +02:00
Christian Halstrick 82d75f31d4 Merge "Extend merge support for bare repositories" 2010-09-27 04:46:06 -04:00
Robin Rosenberg be9d096986 Use only a single instance for NLS translation bundles
As findbugs pointed out, there was a small risk for creating multiple instances of
translation bundles. If that happens, drop the second instance.

Change-Id: I3aacda86251d511f6bbc2ed7481d561449ce3b6c
Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
2010-09-26 09:46:35 +02:00
Shawn O. Pearce b533a72934 Implement HistogramDiff
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>
2010-09-24 19:10:09 -07:00
Shawn O. Pearce 9bcf391355 Micro-optimize EditList.addAll
Pass through the addAll request to our underlying ArrayList.

This way the underlying ArrayList grows no more than once during the
call, which may be important if the list was originally allocated
at the default size of 16, but 64 Edits are being added.

Change-Id: I31c3261e895766f82c3c832b251a09f6e37e8860
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-09-24 13:58:12 -07:00
Chris Aniszczyk 39734f2908 Update FetchCommand with dry run and thin options
FetchCommand was missing the ability to set dry run and thin
preferences on the transport operation.

Change-Id: I0bef388a9b8f2e3a01ecc9e7782aaed7f9ac82ce
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
2010-09-24 15:33:38 -05:00
Dmitry Fink 906887a735 Extend merge support for bare repositories
Optional inCore parameter to Resolver/Strategy will
instruct it to perform all the operations in memory
and avoid modifying working folder even if there is one.

Change-Id: I5b873dead3682f79110f58d7806e43f50bcc5045
2010-09-24 11:01:20 -07:00
Shawn O. Pearce 11f99fecfd Reduce content hash function collisions
The hash code returned by RawTextComparator (or that is used
by the SimilarityIndex) play an important role in the speed of
any algorithm that is based upon them.  The lower the number of
collisions produced by the hash function, the shorter the hash
chains within hash tables will be, and the less likely we are to
fall into O(N^2) runtime behaviors for algorithms like PatienceDiff.

Our prior hash function was absolutely horrid, so replace it with
the proper definition of the DJB hash that was originally published
by Professor Daniel J. Bernstein.

To support this assertion, below is a table listing the maximum
number of collisions that result when hashing the unique lines in
each source code file of 3 randomly chosen projects:

  test_jgit: 931 files; 122 avg. unique lines/file
   Algorithm    | Collisions
   -------------+-----------
   prior_hash            418
   djb                     5
   sha1                    6
   string_hash31          11

  test_linux26: 30198 files; 258 avg. unique lines/file
   Algorithm    | Collisions
   -------------+-----------
   prior_hash           8675
   djb                    32
   sha1                    8
   string_hash31          32

  test_frameworks_base: 8381 files; 184 avg. unique lines/file
   Algorithm    | Collisions
   -------------+-----------
   prior_hash           4615
   djb                    10
   sha1                    6
   string_hash31          13

We can clearly see that prior_hash performed very poorly, resulting
in 8,675 collisions (elements in the same hash bucket) for at least
one file in the Linux kernel repository.  This leads to some very
bad O(N) style insertion and lookup performance, even though the
hash table was sized to be the next power-of-2 larger than the
total number of unique lines in the file.

The djb hash we are replacing prior_hash with performs closer to
SHA-1 in terms of having very few collisions.  This indicates it
provides a reasonably distributed output for this type of input,
despite being a much simpler algorithm (and therefore will be much
faster to execute).

The string_hash31 function is provided just to compare results with,
it is the algorithm commonly used by java.lang.String hashCode().

However, life isn't quite this simple.

djb produces a 32 bit hash code, but our hash tables are always
smaller than 2^32 buckets.  Mashing the 32 bit code into an array
index used to be done by simply taking the lower bits of the hash
code by a bitwise and operator.  This unfortuntely still produces
many collisions, e.g. 32 on the linux-2.6 repository files.

From [1] we can apply a final "cleanup" step to the hash code to
mix the bits together a little better, and give priority to the
higher order bits as they include data from more bytes of input:

  test_jgit: 931 files; 122 avg. unique lines/file
   Algorithm    | Collisions
   -------------+-----------
   prior_hash            418
   djb                     5
   djb + cleanup           6

  test_linux26: 30198 files; 258 avg. unique lines/file
   Algorithm    | Collisions
   -------------+-----------
   prior_hash           8675
   djb                    32
   djb + cleanup           7

  test_frameworks_base: 8381 files; 184 avg. unique lines/file
   Algorithm    | Collisions
   -------------+-----------
   prior_hash           4615
   djb                    10
   djb + cleanup           7

This is a massive improvement, as the number of collisions for
common inputs drops to acceptable levels, and we haven't really
made the hash functions any more complex than they were before.

[1] http://lkml.org/lkml/2009/10/27/404

Change-Id: Ia753b695de9526a157ddba265824240bd05dead1
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-09-23 17:44:53 -07:00
Chris Aniszczyk fcc3349cfc Add reflog message to TagCommand
Ensure we update the reflog when tagging.

Change-Id: I3f4a4d68cbfc62d2276e3a47e3e3720f02cb2522
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
2010-09-22 10:47:44 -05:00
Shawn O. Pearce 857d68d173 Perform common start/end elimination by default for DiffAlgorithm
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>
2010-09-21 18:00:59 -07:00