Commit Graph

231 Commits

Author SHA1 Message Date
Jeff Schumacher 9a48de86d8 Added file path similarity to scoring metric in rename detection
The scoring method was not taking into account the similarity of
the file paths and file names. I changed the metric so that it is 99%
based on content (which used to be 100% of the old metric), and 1%
based on path similarity. Of that 1%, half (.5% of the total final
score) is based on the actual file names (e.g. "foo.java"), and half
on the directory (e.g. "src/com/foo/bar/").

Change-Id: I94f0c23bf6413c491b10d5625f6ad7d2ecfb4def
2010-07-12 12:52:05 -07:00
Jeff Schumacher 4c14b7869d Fixed potential div by zero bug
The scoring logic in SimilarityIndex was dividing by the max file
size. If both files are empty, this would cause a div by zero
error. This case cannot currently happen, since two empty files
would have the same SHA1, and would therefore be caught in the
earlier SHA1 based detection pass. Still, if this logic eventually
gets separated from that pass, a div by zero error would occur.

I changed the logic to instead consider two empty files to have a
similarity score of 100.

Change-Id: Ic08e18a066b8fef25bb5e7c62418106a8cee762a
2010-07-12 12:24:42 -07:00
Jeff Schumacher 64b9458640 Added file size based rename detection optimization
Prior to this change, files that were very different in size (enough
so that they could not have enough in common to be detected as
renames) were still having their scores calculated. I added an
optimization to skip such files. For example, if the rename detection
threshold is 60%, the larger file is 200kb, and the smaller file is
50kb, the pair cannot be counted as a rename since they cannot
possibly share 60% of their content in common. (200*.6=120, 120>50)

Change-Id: Icd8315412d5de6292839778e7cea7fe6f061b0fc
2010-07-12 12:24:42 -07:00
Jeff Schumacher a8b29afd82 Create FileHeader from DiffEntry
Added support for converting DiffEntrys to FileHeaders. FileHeaders
are DiffEntrys with a buffer containing the diff output as well as
a list of HunkHeaders. The HunkHeaders contain EditLists. The
createFileHeader(DiffEntry) method in DiffFormatter performs a Myers
Diff on the files refered to by the DiffEntry, then puts the returned
EditList into a single HunkHeader, which is then put into the
FileHeader to be returned. It also generates the appropriate diff
header an puts it into the FileHeader's buffer. The rest of the diff
output, which would normally be parsed to generate the HunkHeaders,
is not generated. In fact, the purpose of this method is to avoid
the costly diff output generation and parsing normally required to
create a FileHeader.

Change-Id: I7d8b18c0f6c85e3d02ad58995d3d231e69af5887
2010-07-08 16:58:55 -07:00
Shawn O. Pearce 1913b41bc7 log: Implement --follow
The FollowFilter can be installed on a RevWalk to cause the path
to be updated through rename detection when the affected file is
found to be added to the project.

The filter works reasonably well, for example we can follow the
history of the fsck command in git-core:

  $ jgit log --name-status --follow builtin/fsck.c | grep ^R
  R100	builtin-fsck.c	builtin/fsck.c
  R099	fsck.c	builtin-fsck.c
  R099	fsck-objects.c	fsck.c
  R099	fsck-cache.c	fsck-objects.c

Change-Id: I4017bcfd150126aa342fdd423a688493ca660a1f
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-07-03 18:17:55 -07:00
Shawn O. Pearce e9de5643fa Cache the diff configuration section
This way we don't have to reparse for the rename limit every time
we create a new rename detector for a repository.

Change-Id: I669d031690b85ef4da5e39189be7173fb773fc56
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-07-03 18:17:52 -07:00
Shawn O. Pearce 8a0c58394d log: Add whitespace ignore options
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>
2010-07-03 17:32:47 -07:00
Shawn O. Pearce bd8740dc14 Format submodule links during differences
Instead of crashing, output a submodule link with the simple
"Subproject commit $fullid\n" syntax used by C Git.

Change-Id: Iae8646941683fb19b73fb038217d2e3bf5f77fa9
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-07-03 16:59:06 -07:00
Shawn O. Pearce 5be90be996 Redo DiffFormatter API to be easier to use
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>
2010-07-03 16:58:37 -07:00
Shawn O. Pearce 04a9d23b9a log, diff: Add rename detection support
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>
2010-07-03 16:32:03 -07:00
Shawn O. Pearce 978535b090 Implement similarity based rename detection
Content similarity based rename detection is performed only after
a linear time detection is performed using exact content match on
the ObjectIds.  Any names which were paired up during that exact
match phase are excluded from the inexact similarity based rename,
which reduces the space that must be considered.

During rename detection two entries cannot be marked as a rename
if they are different types of files.  This prevents a symlink from
being renamed to a regular file, even if their blob content appears
to be similar, or is identical.

Efficiently comparing two files is performed by building up two
hash indexes and hashing lines or short blocks from each file,
counting the number of bytes that each line or block represents.

Instead of using a standard java.util.HashMap, we use a custom
open hashing scheme similiar to what we use in ObjecIdSubclassMap.
This permits us to have a very light-weight hash, with very little
memory overhead per cell stored.

As we only need two ints per record in the map (line/block key and
number of bytes), we collapse them into a single long inside of
a long array, making very efficient use of available memory when
we create the index table.  We only need object headers for the
index structure itself, and the index table, but not per-cell.
This offers a massive space savings over using java.util.HashMap.

The score calculation is done by approximating how many bytes are
the same between the two inputs (which for a delta would be how much
is copied from the base into the result).  The score is derived by
dividing the approximate number of bytes in common into the length
of the larger of the two input files.

Right now the SimilarityIndex table should average about 1/2 full,
which means we waste about 50% of our memory on empty entries
after we are done indexing a file and sort the table's contents.
If memory becomes an issue we could discard the table and copy all
records over to a new array that is properly sized.

Building the index requires O(M + N log N) time, where M is the
size of the input file in bytes, and N is the number of unique
lines/blocks in the file.  The N log N time constraint comes
from the sort of the index table that is necessary to perform
linear time matching against another SimilarityIndex created for
a different file.

To actually perform the rename detection, a SxD matrix is created,
placing the sources (aka deletions) along one dimension and the
destinations (aka additions) along the other.  A simple O(S x D)
loop examines every cell in this matrix.

A SimilarityIndex is built along the row and reused for each
column compare along that row, avoiding the costly index rebuild
at the row level.  A future improvement would be to load a smaller
square matrix into SimilarityIndexes and process everything in that
sub-matrix before discarding the column dimension and moving down
to the next sub-matrix block along that same grid of rows.

An optional ProgressMonitor is permitted to be passed in, allowing
applications to see the progress of the detector as it works through
the matrix cells.  This provides some indication of current status
for very long running renames.

The default line/block hash function used by the SimilarityIndex
may not be optimal, and may produce too many collisions.  It is
borrowed from RawText's hash, which is used to quickly skip out of
a longer equality test if two lines have different hash functions.
We may need to refine this hash in the future, in order to minimize
the number of collisions we get on common source files.

Based on a handful of test commits in JGit (especially my own
recent rename repository refactoring series), this rename detector
produces output that is very close to C Git.  The content similarity
scores are sometimes off by 1%, which is most probably caused by
our SimilarityIndex type using a different hash function than C
Git uses when it computes the delta size between any two objects
in the rename matrix.

Bug: 318504
Change-Id: I11dff969e8a2e4cf252636d857d2113053bdd9dc
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-07-03 16:32:03 -07:00
Jeff Schumacher cb8e1e6014 Added a preliminary version of rename detection
JGit does not currently do rename detection during diffs. I added
a class that, given a TreeWalk to iterate over, can output a list
of DiffEntry's for that TreeWalk, taking into account renames. This
class only detects renames by SHA1's. More complex rename detection,
along the lines of what C Git does will be added later.

Change-Id: I93606ce15da70df6660651ec322ea50718dd7c04
2010-07-01 17:33:53 -07:00
Jeff Schumacher 7b0b4110ed Refactored code out of FileHeader to facilitate rename detection
Refactored a superclass out of FileHeader called DiffEntry that holds
the more general data from FileHeader that is useful in rename
detection (old/new Ids, modes, names, as well as changeType and
score). FileHeader is now a DiffEntry that adds Hunks, parsing
abilities, etc.

Change-Id: I8398728cd218f8c6e98f7a4a7f2f342391d865e4
2010-06-30 17:53:27 -07:00
Dmitry Neverov 44854741c5 Fix missing flush in StreamCopyThread
It is possible that StreamCopyThread will not flush everything
from it's src to it's dst.  In most cases StreamCopyThread works
like this:

  in loop:
    n = src.read(buf);
    dst.write(buf, 0, n);

and when we want to flush, we interrupt() StreamCopyThread and it
flushes everything it wrote to dst.

The problem is that our interrupt() could interrupt reading. In this
case we will flush everything we wrote to dst, but not everything
we wrote to src.

Change-Id: Ifaf4d8be87535c7364dd59b217dfc631460018ff
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-06-30 10:48:44 -07:00
Jeff Schumacher 9f2249bd26 Added check for binary files while diffing
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
2010-06-29 17:23:00 -07:00
Shawn Pearce 3fd4918852 Merge changes Ie56301aa,Ic2f79e85
* changes:
  Added further support for whitespace ignoring during diff
  Added support for whitespace ignoring
2010-06-28 20:27:04 -04:00
Jeff Schumacher 9869ef2592 Added further support for whitespace ignoring during diff
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
2010-06-28 17:25:19 -07:00
Jeff Schumacher 543235b805 Added support for whitespace ignoring
JGit did not have support for skipping whitespace when comparing
lines in RawText objects. I added a subclass of RawText that skips
whitespace in its equals and hashCode methods. I used a subclass
rather than adding functionality into RawText so that performance
would not be impacted by extra logic.

This class only supports ignoring all whitespace. Others will follow
that allow other forms of whitespace ignoring.

Change-Id: Ic2f79e85215e48d3fd53ec1b4ad13373dd183a4a
2010-06-28 10:59:10 -07:00
Shawn O. Pearce 5ed96eb7f4 UploadPack: Avoid unnecessary flush in smart HTTP
Under smart HTTP the biDirectionalPipe flag is false, and we return
back immediately at this point in the negotiation process.  There is
no need to flush the stream to the client, the request is over and
it will be automatically flushed out by the higher level servlet
that invoked us.  Avoiding flush here allows us to only use flush
after a progress message is sent during pack generation.

Change-Id: Id0c8b7e95e3be6ca4c1b479e096bed6b0283b828
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-06-23 16:54:15 -07:00
Shawn O. Pearce 066df3d1a1 Add MutableObjectId.copyFrom(AnyObjectId)
This simplifies the PackIndex code, which is trying to quickly copy
an existing ObjectId into a MutableObjectId.  Rather than having
the PackIndex violate the ObjectId's internals, expose a copy from
function similar to the other ones for copying from raw byte arrays
or hex formatted strings.

Change-Id: I142635cbece54af2ab83c58477961ce925dc8255
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-06-23 16:54:15 -07:00
Shawn O. Pearce 677b9b17e2 Expose AnyObjectId compareTo(byte[]) and compareTo(int[])
Storage systems can use these implementations to compare a passed
AnyObjectId with a stored representation of an ObjectId in the
canonical network byte order format.  This can be useful to do a
binary search, or just linear scan, over an encoded storage file.

Change-Id: I8c72993c4f4c6e98d599ac2c9867453752f25fd2
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-06-23 16:54:15 -07:00
Shawn O. Pearce 864cc3de10 Expose RefWriter constructor taking RefList
An implementation might prefer to use the RefList type here, and
RefList is part of our public API.  Expose the constructor so callers
who have a RefList can take advantage of the existing sorting.

Change-Id: I545867f85aa2c479d2d610024ebbe318144709c8
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-06-23 16:54:15 -07:00
Shawn O. Pearce bfc43c13bc Expose RefUpdate constructor to any subclass
When we finally move RefDirectory to the new storage.file package,
its associated RefDirectoryUpdate will need visiblity to this
constructor in order to initialize itself.  This is true of any
other repository implementation, so make it protected rather than
package level visible.

Change-Id: If838aec9baeb80ee2f12dcbca717657c725a9242
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-06-23 16:54:14 -07:00
Shawn O. Pearce 8e40697047 Expose repository change event constructors
Repository implementations outside of .lib need to be able to
create these events and deliver them to listening application code.

Expose and document the constructors so that they are visible when
we move FileRepository into storage.file.FileRepository.

Change-Id: I7fb6e8f4f5fdab683c5ebb5267673aa6d5b560bb
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-06-23 16:54:14 -07:00
Shawn O. Pearce b3254d1159 isValidRefName: Inline the forbidden ref suffix of ".lock"
A Git reference name must never end with ".lock", as it would
confuse any existing C client that tries to obtain a clone of the
repository over the network.  Even if the repository isn't on a
local filesystem, it still should ban that suffix.

Because I plan to move LockFile to storage.file and make it a private
implementation detail of the local file system storage model,
we can't rely on its package level SUFFIX field here.  Making it
public probably won't work long-term either, as I also plan to
pull storage.file into its own separate project that depends on
the core library.

So, just inline the constant here.  Its as foribidden as ":" is.

Change-Id: If85076861baeacc183b82696375a13e935ba8836
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-06-23 16:54:14 -07:00
Shawn Pearce f3186974b6 Merge "Fix line endings" 2010-06-18 18:15:53 -04:00
Matthias Sohn 767fb175ed Fix line endings
Some sources had dos line endings. Also configure all projects to use
unix line endings and UTF-8 text encoding.

Change-Id: I8fc9a1dbb219ffa91d1b3011b3b11b7e48e74ca7
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2010-06-18 23:36:18 +02:00
Shawn Pearce 3149f971e0 Merge ""Bare" Repository should not return working directory." 2010-06-16 22:34:46 -04:00
Andrew Bayer 068eb92710 Make ObjectId, RefSpec, RemoteConfig, URIish serializable
Modifications to various classes in order to allow serialization
for use of JGit in Hudson's git plugin.

Change-Id: If088717d3da7483538c00a927e433a74085ae9e6
2010-06-16 16:10:28 -07:00
Mathias Kinzler 3c51b35e03 "Bare" Repository should not return working directory.
If a repository is "bare", it currently still returns a working directory.
This conflicts with the specification of "bare"-ness.

Bug: 311902

Change-Id: Ib54b31ddc80b9032e6e7bf013948bb83e12cfd88
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>
2010-06-16 08:50:26 +02:00
Chris Aniszczyk 8a11ac3d69 Merge "Add missing @Override tags in AlternateRepositoryDatabase" 2010-06-15 11:40:04 -04:00
Mathias Kinzler c1c1300a74 Allow to read configured keys
Currently, there is no way to read the content
of the Git Configuration in a  way that would
allow to list all configured values generically.
This change extends the Config class in such a
way as to being able to get a list of sections and
to get a list of names for any given section or
subsection.
This is required in able to implement proper
configuration handling in EGit (show all the
content of a given configuration similar to 
"git config -l").

Change-Id: Idd4bc47be18ed0e36b11be8c23c9c707159dc830
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>
2010-06-15 10:12:26 +02:00
Shawn Pearce 86fcdc53ad Merge changes I53f71dc0,I3a899a3a,I3e8bd245,Ie7c9db83,If396326e,I6f4cf8da,I3bf96dd0,I3a2a43a1,I292fe88c,Ia1cf40cf
* changes:
  git-servlet: Fix comparing uploadFactory with the wrong DISABLED instance
  Prefer static inner classes
  Override equals for SwingLane since super class PlotLane defines it
  Make sure a Stream is closed upon errors in IpLogGenerator
  Make constant static in RebuildCommitGraph
  Make inner classes static in http code
  Cache filemode in GitIndex 
  Remove unused parent field in PlotLane
  Removed unused repo field in WorkDirCheckout
  Extend DiffFormatter API to simplify styling
2010-06-14 19:59:48 -04:00
Shawn O. Pearce bc238acdc5 Add missing @Override tags in AlternateRepositoryDatabase
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-06-14 12:59:30 -07:00
Shawn O. Pearce 44ba1bc78c Merge branch 'stable-0.8'
* stable-0.8:
  Qualify post-0.8.4 builds
  JGit 0.8.4
  JGit 0.8.3
  Include about.html in org.eclipse.jgit artifact
  Fix build.properties of the JGit feature
  Added the standard SULA for JGit
  Add "resources/" as a source folder

Change-Id: I4ecb0af41184ef84d104345fd1adcc4a240a38f6
2010-06-14 08:12:48 -07:00
Shawn O. Pearce 239ce58553 Start 0.9 development
Change-Id: I84173ece5100f1fcb78168e2e102b649d9466c08
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-06-14 08:11:27 -07:00
Shawn O. Pearce d28a40d679 Qualify post-0.8.4 builds
Change-Id: I21efed66921eb7e1e4010fccc9fa9af6c4150fc1
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-06-14 08:10:08 -07:00
Matthias Sohn 6970edf35a JGit 0.8.4
Created wrong tags for 0.8.3 hence creating another version.

Change-Id: I4e00bbcffe1cf872e2d7e3f3d88d068701fb5330
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2010-06-14 15:42:09 +02:00
Matthias Sohn 5255d66143 JGit 0.8.3
Change-Id: I845da83c74475d74ec25d68f53c0a4738a898550
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2010-06-14 01:34:34 +02:00
Robin Rosenberg 3bf96dd04b Cache filemode in GitIndex
Apparently this was the intention, but never happened

Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
2010-06-13 03:16:32 +02:00
Robin Rosenberg 3a2a43a1dc Remove unused parent field in PlotLane
Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
2010-06-13 03:13:57 +02:00
Robin Rosenberg 292fe88c50 Removed unused repo field in WorkDirCheckout
Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
2010-06-13 03:12:41 +02:00
Robin Rosenberg ce56c5dcc9 Extend DiffFormatter API to simplify styling
Refactor and extend the internals so users can override and
intervene during formatting, e.g. to colorize output.

Change-Id: Ia1cf40cfd4a5ed7dfb6503f8dfc617237bee0659
Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
2010-06-12 15:31:04 +02:00
Matthias Sohn 4269a90aac Include about.html in org.eclipse.jgit artifact
This is required to enable accessing legal info for
org.eclipse.jgit from
Help > About > Installation Details > Plugins

Change-Id: I73f40dd2018112cd23102954d7647ecdbbbf0d89
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2010-06-08 02:41:37 +02:00
Matthias Sohn ab360d06de Add "resources/" as a source folder
Building jgit with pde.build was broken without resources.

Bug:315823
Change-Id: I45be510ada068b3ffab0feb30ec60f2c96a5ca32
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
2010-06-05 14:39:27 +02:00
Marc Strapetz 936e4ab2f2 Repository can be configured with FS
On Windows, FS_Win32_Cygwin has been used if a Cygwin Git installation
is present in the PATH. Assuming that the user works with the Cygwin
Git installation may result in unnecessary overhead if he actually
does not.

Applications built on top of jgit may have more knowledge on the
actually used Git client (Cygwin or not) and hence should be able to
configure which FS to use accordingly.

Change-Id: Ifc4278078b298781d55cf5421e9647a21fa5db24
2010-06-04 19:08:58 -07:00
Robin Rosenberg 920d89d6af Add support for computing a Change-Id à la Gerrit
A Change-Id helps tools like Gerrit Code Review to keeps different
versions of a patch together. The Change-Id is computed as a SHA-1
hash of some of the same basic information as a commit id on the first
commit intended to solve a particular problem and then reused for
updated solutions.

Change-Id: I04334f84e76e83a4185283cb72ea0308b1cb4182
Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
2010-06-04 18:42:14 -07:00
Alex Blewitt 046d1a2ef6 Provide a public entry method to determine whether a URI protocol is supported 2010-06-04 00:38:50 +01:00
Shawn O. Pearce d8ec8527a6 Qualify post-0.8.1 builds
Change-Id: Id86e5876b2f684b2a272c07061a276b054ba410d
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-06-02 15:55:39 -07:00
Shawn O. Pearce be86767d71 JGit 0.8.1
Change-Id: I3d4ac7d0617a3575019e2ed748ed2a298a988340
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2010-06-02 14:47:31 -07:00