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>
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>
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
The core.autocrlf variable can take on three values: false, true,
and input. Parsing it as a boolean is wrong, we instead need to
parse a tri-state enumeration.
Add support for parsing and setting enum values from Java from and
to the text based configuration file, and use that to handle the
autocrlf variable.
Bug: 301775
Change-Id: I81b9e33087a33d2ef2eac89ba93b9e83b7ecc223
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>
When checkReferencedIsReachable is set in ReceivePack we are trying
to prove that the push client is permitted to access an object that
it did not send to us, but that the received objects link to either
via a link inside of an object (e.g. commit parent pointer or tree
member) or by a delta base reference.
To do this check we are making a list of every potential delta base,
and then ensuring that every delta base used appears on this list.
If a delta base does not appear on this list, we abort with an error,
letting the client know we are missing a particular object.
Preventing spurious errors about missing delta base objects requires
us to use the exact same list of potential delta bases as the remote
push client used. This means we must use TOPO ordering, and we
need to enable BOUNDARY sorting so that ObjectWalk will correctly
include any trees found during the enumeration back to the common
merge base between the interesting and uninteresting heads.
To ensure JGit's own push client matches this same potential delta
base list, we need to undo 60aae90d4d ("Disable topological
sorting in PackWriter") and switch back to using the conventional
TOPO ordering for commits in a pack file. This ensures that our
own push client will use the same potential base object list as
checkReferencedIsReachable uses on the receiving side.
Change-Id: I14d0a326deb62a43f987b375cfe519711031e172
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
If the copy instruction was larger than the input buffer given to us,
we copied the wrong part of the base stream during the next read().
This occurred on really big binary files where a copy instruction
of 64k wasn't unreasonable, but the caller's buffer was only 8192
bytes long. We copied the first 8192 bytes correctly, but then
reseeked the base stream back to the start of the copy region on
the second read of 8192 bytes. Instead of a sequence like ABCD
being read into the caller, we read AAAA.
Change-Id: I240a3f722a3eda1ce8ef5db93b380e3bceb1e201
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Exposing isEmpty, getLengthA, getLengthB make it easier to examine
the state of an edit and work with it from higher level code.
The before and after cut routines make it easy to split an edit
that contains another edit, such as to decompose a REPLACE that
contains a common sequence within it.
Change-Id: Id63d6476a7a6b23acb7ab237d414a0a1a7200290
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
We shouldn't escape non-special ASCII characters such as '@' or '~'.
These are valid in a path name on POSIX systems, and may appear as
part of a path in a GNU or Git style patch script. Escaping them
into octal just obfuscates the user's intent, with no gain.
When parsing an escaped octal sequence, we must parse no more
than 3 digits. That is, "\1002" is actually "@2", not the Unicode
character \u0202.
Change-Id: I3a849a0d318e69b654f03fd559f5d7f99dd63e5c
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
If we get an exception while indexing the incoming pack, its likely
a stream corruption. We already report an error to the client, but
we eat the stack trace, which makes debugging issues related to a
bug inside of JGit nearly impossible. Rethrow it under a new type
UnpackException, so embedding servers or applications can catch the
error and provide it to a human who might be able to forward such
traces onto a JGit developer for evaluation.
Change-Id: Icad41148bbc0c76f284c7033a195a6b51911beab
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>
Create a new 'org.eclipse.jgit.api.errors' package to contain
exceptions related to using the Git porcelain API.
Change-Id: Iac1781bd74fbd520dffac9d347616c3334994470
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
When adding or deleting a file, we shouldn't ever prefix /dev/null
with the a/ or b/ prefixes. Doing so is a mistake and confuses a
patch parser which handles /dev/null magically, while a/dev/null is
a file called null in the dev directory of the project.
Also when adding or deleting the "diff --git" line has the "real"
path on both sides, so we should see the following when adding the
file called foo:
diff --git a/foo b/foo
--- /dev/null
+++ b/foo
The --- and +++ lines do not appear in a pure rename or copy delta,
C Git diff seems to omit these, so we now omit them as well. We also
omit the index line when the ObjectIds are exactly equal.
Change-Id: Ic46892dea935ee8bdee29088aab96307d7ec6d3d
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Currently, if a branch is created that has special chars ('#' in the bug),
Config will surround the subsection name with double quotes during
it's toText method which will result in an invalid file after saving the
Config.
Bug: 318249
Change-Id: I0a642f52def42d936869e4aaaeb6999567901001
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>
Extended flags are processed and available via DirCacheEntry's
new isSkipWorkTree() and isIntentToAdd() methods. "resolve-undo"
information is completely ignored since its an optional extension.
Change-Id: Ie6e9c6784c9f265ca3c013c6dc0e6bd29d3b7233
The merge algorithm was reporting conflicts which where to big.
Example: The common base was "ABC", the "ours" version contained
"AB1C" (the addition of "1" after pos 2) and the "theirs" version also
contained "AB1C". We have two potentially conflicting edits in the
same region which happen to bring in exactly the same content. This
should not be a conflict - but was previously reported as
"AB<<<1===1>>>C".
This is fixed by checking every conflicting chunk whether the
conflicting regions have a common prefix or suffix and by removing
this regions from the conflict.
Change-Id: I4dc169b8ef7a66ec6b307e9a956feef906c9e15e
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
This adds the first merge strategy to JGit which does real
content-merges if necessary. The new merge strategy "resolve" takes as
input three commits: a common base, ours and theirs. It will simply takeover
changes on files which are only touched in ours or theirs. For files
touched in ours and theirs it will try to merge the two contents
knowing taking into account the specified common base.
Rename detection has not been introduced for now.
Change-Id: I49a5ebcdcf4f540f606092c0f1dc66c965dc66ba
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
Signed-off-by: Stefan Lay <stefan.lay@sap.com>
On Mac OS X MyerDiffPerformanceTest was failing since during the
first few tests the JIT compiler is running in parallel slowing down
the tests. When setting the JVM option -Xbatch forcing the JIT to do
its work prior to running the code this effect can be avoided. Instead
we chose to run some tests without recording prior to the recorded
tests since relying on -X JVM parameters isn't portable across JVMs.
Use 10k * powers of 2 as sample size instead of odd numbers used
before and also improve formatting of performance readings.
Bug: 323766
Change-Id: I9a46d73f81a785f399d3cf5a90c8c0516526e048
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
Use 3 different types of LargeObjectException for the 3 major ways
that we can fail to load an object. For each of these use a unique
string translation which describes the root cause better than just
the ObjectId.name() does.
Change-Id: I810c98d5691b74af9fc6cbd46fc9879e35a7bdca
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Add an explicit test case to check that we don't
overwrite dirty files in case Head & Index are
equal.
Change-Id: I6266d0a449e55369d2d0a048694dca5565c5fcf3
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
This reverts commit db4c516f67 since
it breaks compatibility with Eclipse 3.5 which can no longer import
the projects
Bug: 323390
Change-Id: I3cc91364a6747cfcb4c611a9be5258f81562f726
A tag command is added to the Git porcelain API. Tests were
also added to stress test the tag command.
Change-Id: Iab282a918eb51b0e9c55f628a3396ff01c9eb9eb
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Implementation of a checkout (or 'git read-tree') operation which
works together with DirCache. This implementation does similar things
as WorkDirCheckout which main problem is that it works with deprecated
GitIndex. Since GitIndex doesn't support multiple stages of a file
which is required in merge situations this new implementation is
required to enable merge support.
Change-Id: I13f0f23ad60d98e5168118a7e7e7308e066ecf9c
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
Otherwise PackFileTest.testDelta_LargeObjectChain() reproducibly
fails with OutOfMemoryError on Mac OS X 10.6.4.
Change-Id: I6a55ff9ba181102606a0d99ffd52392a1615a422
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Updates the project level settings to run the formatter
on save on only on the edited lines.
Change-Id: I26dd69d0c95e6d73f9fdf7031f3c1dbf3becbb79
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
We should use JUnit4 for tests. This patch updates
the MANIFEST.MF and respective launch configurations.
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
PersonIdent should be parsable for an invalid commit which
contains multiple authors, like "A <a@a.org>, B <b@b.org>".
PersonIdent(String) constructor now delegates to
RawParseUtils.parsePersonIdent().
Change-Id: Ie9798d36d9ecfcc0094ca795f5a44b003136eaf7
Because we are using the large stream size, we have to be
above the STREAM_THRESHOLD constant, which I just increased.
Change-Id: I6f10ec8558d9f751d4b547fcae05af94f1c8866b
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
We can now resolve expressions that reference a path within a
commit, designating a specific revision of a specific tree or
file in the project.
Change-Id: Ie6a8be629d264d72209db894bd680c5900035cc0
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
We now match on the -gABBREV style output created by git describe
when its describing a non-tagged commit, and resolve that back to
the full ObjectId using the abbreviation resolution feature that
we already support.
Change-Id: Ib3033f9483d9e1c66c8bb721ff48d4485bcdaef1
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Calling it by the old numerical numbering system makes it really
hard to find the test that tests Repository.resolve(String).
Change-Id: I92d0ecbc8d66ce21bfed08888eeedf1300ffa594
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Its wrong to return null if we are resolving an abbreviation and we
have proven it matches more than one object. We know how to resolve
it if we had more nybbles, as there are two or more objects with the
same prefix. Declare that to the caller quite clearly by giving them
an AmbiguousObjectException.
Change-Id: I01bb48e587e6d001b93da8575c2c81af3eda5a32
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Some algorithms are coded in a way that requires us to provide them
the entire object contents as a contiguous byte array. The parsers
in RevCommit and RevTag, or our RawText objects are really good
examples of these.
Instead of duplicating this logic everywhere, lets put it into the
base ObjectLoader type. That way the caller only needs to give us
their upper size bound, and we'll do the rest of the heavy work to
figure out if the object still fits within that bound, and get them
an array that has the complete contents.
Change-Id: Id95a7f79d2b97e39f6949370ccca2f2c9cfb1a0f
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
Shawn O. Pearce
Chris Aniszczyk
Stefan Lay
Matthias Sohn
Christian Halstrick
Chris West (Faux)
Robin Rosenberg
Mathias Kinzler
Marc Strapetz