The "argc" and "argv" names made sense when the struct was argv_array,
but now they're just confusing. Let's rename them to "nr" (which we use
for counts elsewhere) and "v" (which is rather terse, but reads well
when combined with typical variable names like "args.v").
Note that we have to update all of the callers immediately. Playing
tricks with the preprocessor is hard here, because we wouldn't want to
rewrite unrelated tokens.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Code which split an argv_array call across multiple lines, like:
argv_array_pushl(&args, "one argument",
"another argument", "and more",
NULL);
was recently mechanically renamed to use strvec, which results in
mis-matched indentation like:
strvec_pushl(&args, "one argument",
"another argument", "and more",
NULL);
Let's fix these up to align the arguments with the opening paren. I did
this manually by sifting through the results of:
git jump grep 'strvec_.*,$'
and liberally applying my editor's auto-format. Most of the changes are
of the form shown above, though I also normalized a few that had
originally used a single-tab indentation (rather than our usual style of
aligning with the open paren). I also rewrapped a couple of obvious
cases (e.g., where previously too-long lines became short enough to fit
on one), but I wasn't aggressive about it. In cases broken to three or
more lines, the grouping of arguments is sometimes meaningful, and it
wasn't worth my time or reviewer time to ponder each case individually.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We eventually want to drop the argv_array name and just use strvec
consistently. There's no particular reason we have to do it all at once,
or care about interactions between converted and unconverted bits.
Because of our preprocessor compat layer, the names are interchangeable
to the compiler (so even a definition and declaration using different
names is OK).
This patch converts all of the remaining files, as the resulting diff is
reasonably sized.
The conversion was done purely mechanically with:
git ls-files '*.c' '*.h' |
xargs perl -i -pe '
s/ARGV_ARRAY/STRVEC/g;
s/argv_array/strvec/g;
'
We'll deal with any indentation/style fallouts separately.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This requires updating #include lines across the code-base, but that's
all fairly mechanical, and was done with:
git ls-files '*.c' '*.h' |
xargs perl -i -pe 's/argv-array.h/strvec.h/'
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If the supplied integer for "precision" is negative in
`"%.*s", len, line` then it is ignored. So the current code is
equivalent to just `"%s", line` because it is executed only if
`len` is negative.
Fix this by saving the value of `len` before overwriting it with the
return value of `parse_git_diff_header()`.
Signed-off-by: Vasil Dimov <vd@FreeBSD.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
`git range-diff` calls `git log` internally and tries to parse its
output. But `git log` output can be customized by the user in their
git config and for certain configurations either an error will be
returned by `git range-diff` or it will crash.
To fix this explicitly set the output format of the internally
executed `git log` with `--pretty=medium`. Because that cancels
`--notes`, add explicitly `--notes` at the end.
Also, make sure we never crash in the same way - trying to dereference
`util` which was never created and has remained NULL. It would happen
if the first line of `git log` output does not begin with 'commit '.
Alternative considered but discarded - somehow disable all git configs
and behave as if no config is present in the internally executed
`git log`, but that does not seem to be possible. GIT_CONFIG_NOSYSTEM
is the closest to it, but even with that we would still read
`.git/config`.
Signed-off-by: Vasil Dimov <vd@FreeBSD.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The contents pointed to by `diffopt` and `other_arg` should not be
modified. Mark these as `const` to indicate this.
Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When a commit being range-diff'd has a note attached to it, the note
will be compared as well. However, if a user has multiple notes refs or
if they want to suppress notes from being printed, there is currently no
way to do this.
Pass through `--[no-]notes[=<ref>]` to the `git log` call so that this
option is customizable.
Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When notes were included in the output of range-diff, they were just
mashed together with the rest of the commit message. As a result, users
wouldn't be able to clearly distinguish where the commit message ended
and where the notes started.
Output a `## Notes ##` header when notes are detected so that notes can
be compared more clearly.
Note that we handle case of `Notes (<ref>): -> ## Notes (<ref>) ##` with
this code as well. We can't test this in this patch, however, since
there is currently no way to pass along different notes refs to `git
log`. This will be fixed in a future patch.
Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since these macros already take a `keyvar' pointer of a known type,
we can rely on OFFSETOF_VAR to get the correct offset without
relying on non-portable `__typeof__' and `offsetof'.
Argument order is also rearranged, so `keyvar' and `member' are
sequential as they are used as: `keyvar->member'
Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
`hashmap_free_entries' behaves like `container_of' and passes
the offset of the hashmap_entry struct to the internal
`hashmap_free_' function, allowing the function to free any
struct pointer regardless of where the hashmap_entry field
is located.
`hashmap_free' no longer takes any arguments aside from
the hashmap itself.
Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
And add *_entry variants to perform container_of as necessary
to simplify most callers.
Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is less error-prone than "const void *" as the compiler
now detects invalid types being passed.
Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is less error-prone than "void *" as the compiler now
detects invalid types being passed.
Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
C compilers do type checking to make life easier for us. So
rely on that and update all hashmap_entry_init callers to take
"struct hashmap_entry *" to avoid future bugs while improving
safety and readability.
Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When parsing the diffs, `range-diff` expects to see the prefixes `a/`
and `b/` in the diff headers.
These prefixes can be forced off via the config setting
`diff.noprefix=true`. As `range-diff` is not prepared for that
situation, this will cause a segmentation fault.
Let's avoid that by passing the `--no-prefix` option to the `git log`
process that generates the diffs that `range-diff` wants to parse.
And of course expect the output to have no prefixes, then.
Reported-by: Michal Suchánek <msuchanek@suse.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add the section headers/hunk headers we introduced in the previous
commits to the outer diff's hunk headers. This makes it easier to
understand which change we are actually looking at. For example an
outer hunk header might now look like:
@@ Documentation/config/interactive.txt
while previously it would have only been
@@
which doesn't give a lot of context for the change that follows.
For completeness also add section headers for the commit metadata and
the commit message, although they are arguably less important.
Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a range-diff it's not always clear which file a certain funcname of
the inner diff belongs to, because the diff header (or section header
as added in a previous commit) is not always visible in the
range-diff.
Add the filename to the inner diffs header, so it's always visible to
users.
This also allows us to add the filename + the funcname to the outer
diffs hunk headers using a custom userdiff pattern, which will be done
in the next commit.
Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Currently range-diff keeps the diff header of the inner diff
intact (apart from stripping lines starting with index). This diff
header is somewhat useful, especially when files get different
names in different ranges.
However there is no real need to keep the whole diff header for that.
The main reason we currently do that is probably because it is easy to
do.
Introduce a new range diff hunk header, that's enclosed by "##",
similar to how line numbers in diff hunks are enclosed by "@@", and
give human readable information of what exactly happened to the file,
including the file name.
This improves the readability of the range-diff by giving more concise
information to the users. For example if a file was renamed in one
iteration, but not in another, the diff of the headers would be quite
noisy. However the diff of a single line is concise and should be
easier to understand.
Additionally, this allows us to add these range diff section headers to
the outer diffs hunk headers using a custom userdiff pattern, which
should help making the range-diff more readable.
Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The line count in the outer diff's hunk headers of a range diff is not
all that interesting. It merely shows how far along the inner diff
are on both sides. That number is of no use for human readers, and
range-diffs are not meant to be machine readable.
In a subsequent commit we're going to add some more contextual
information such as the filename corresponding to the diff to the hunk
headers. Remove the unnecessary information, and just keep the "@@"
to indicate that a new hunk of the outer diff is starting.
Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When postprocessing the inner diff in range-diff, we currently replace
the whole hunk header line with just "@@". This matches how 'git
tbdiff' used to handle hunk headers as well.
Most likely this is being done because line numbers in the hunk header
are not relevant without other changes. They can for example easily
change if a range is rebased, and lines are added/removed before a
change that we actually care about in our ranges.
However it can still be useful to have the function name that 'git
diff' extracts as additional context for the change.
Note that it is not guaranteed that the hunk header actually shows up
in the range-diff, and this change only aims to improve the case where
a hunk header would already be included in the final output.
Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Currently range-diff uses the 'strbuf_getline()' function for doing
its line by line processing. In a future patch we want to do parts of
that parsing using the 'parse_git_diff_header()' function. That
function does its own line by line reading of the input, and doesn't
use strbufs. This doesn't match with how we do the line-by-line
processing in range-diff currently.
Switch range-diff to do our own line by line parsing, so we can re-use
the 'parse_git_diff_header()' function later.
Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fix the indentation of the function parameters for a couple of
functions, to match the style in the rest of the file.
Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Stop leaking how the primary output of format-patch is customized to
the range-diff machinery and instead let the latter use its own
"reasonable default", in order to correct the breakage introduced by
a5170794 ("Merge branch 'ab/range-diff-no-patch'", 2018-11-18) on
the 'master' front. "git format-patch --range-diff..." without any
weird diff option started to include the "range-diff --stat" output,
which is rather useless right now, that made the whole thing
unusable and this is probably the least disruptive way to whip the
codebase into a shippable shape.
We may want to later make the range-diff driven by format-patch more
configurable, but that would have to wait until we have a good
design.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "--no-patch" option, which can be used to get a high-level
overview without the actual line-by-line patch difference shown, of
the "range-diff" command was earlier broken, which has been
corrected.
* ab/range-diff-no-patch:
range-diff: make diff option behavior (e.g. --stat) consistent
range-diff: fix regression in passing along diff options
range-diff doc: add a section about output stability
Make the behavior when diff options (e.g. "--stat") are passed
consistent with how "diff" behaves.
Before 73a834e9e2 ("range-diff: relieve callers of low-level
configuration burden", 2018-07-22) running range-diff with "--stat"
would produce stat output and the diff output, as opposed to how
"diff" behaves where once "--stat" is specified "--patch" also needs
to be provided to emit the patch output.
As noted in a previous change ("range-diff doc: add a section about
output stability", 2018-11-07) the "--stat" output with "range-diff"
is useless at the moment.
But we should behave consistently with "diff" in anticipation of such
output being useful in the future, because it would make for confusing
UI if "diff" and "range-diff" behaved differently when it came to how
they interpret diff options.
The new behavior is also consistent with the existing documentation
added in ba931edd28 ("range-diff: populate the man page",
2018-08-13). See "[...]also accepts the regular diff options[...]" in
git-range-diff(1).
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The interface into "xdiff" library used to discover the offset and
size of a generated patch hunk by first formatting it into the
textual hunk header "@@ -n,m +k,l @@" and then parsing the numbers
out. A new interface has been introduced to allow callers a more
direct access to them.
* jk/xdiff-interface:
xdiff-interface: drop parse_hunk_header()
range-diff: use a hunk callback
diff: convert --check to use a hunk callback
combine-diff: use an xdiff hunk callback
diff: use hunk callback for word-diff
diff: discard hunk headers for patch-ids earlier
diff: avoid generating unused hunk header lines
xdiff-interface: provide a separate consume callback for hunks
xdiff: provide a separate emit callback for hunks
In 73a834e9e2 ("range-diff: relieve callers of low-level configuration
burden", 2018-07-22) we broke passing down options like --no-patch,
--stat etc.
Fix that regression, and add a test asserting the pre-73a834e9e2
behavior for some of these diff options.
As noted in a change leading up to this ("range-diff doc: add a
section about output stability", 2018-11-07) the output is not meant
to be stable. So this regression test will likely need to be tweaked
once we get a "proper" --stat option.
See
https://public-inbox.org/git/nycvar.QRO.7.76.6.1811071202480.39@tvgsbejvaqbjf.bet/
for a further explanation of the regression. The fix here is not the
same as in Johannes's on-list patch, for reasons that'll be explained
in a follow-up commit.
The quoting of "EOF" here mirrors that of an earlier test. Perhaps
that should be fixed, but let's leave that up to a later cleanup
change.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we count the lines in a diff, we don't actually care about the
contents of each line. By using a hunk callback, we tell xdiff that it
does not need to even bother generating a hunk header line, saving a
small amount of work.
Arguably we could even ignore the hunk headers completely, since we're
just computing a cost function between patches. But doing it this way
maintains the exact same behavior before and after.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The previous commit taught xdiff to optionally provide the hunk header
data to a specialized callback. But most users of xdiff actually use our
more convenient xdi_diff_outf() helper, which ensures that our callbacks
are always fed whole lines.
Let's plumb the special hunk-callback through this interface, too. It
will follow the same rule as xdiff when the hunk callback is NULL (i.e.,
continue to pass a stringified hunk header to the line callback). Since
we add NULL to each caller, there should be no behavior change yet.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If we have `submodule.diff = log' in the configuration file
or `--submodule=log' is given as argument, range-diff fails
to compare both diffs and we only get the following output:
Submodule a 0000000...0000000 (new submodule)
Even if the repository doesn't have any submodule.
That's because the mode in diff_filespec is not correct and when
flushing the diff, down in builtin_diff() we will enter the condition:
if (o->submodule_format == DIFF_SUBMODULE_LOG &&
(!one->mode || S_ISGITLINK(one->mode)) &&
(!two->mode || S_ISGITLINK(two->mode))) {
show_submodule_summary(o, one->path ? one->path : two->path,
&one->oid, &two->oid,
two->dirty_submodule);
return;
It turns out that S_ISGITLINK will return true (mode == 0160000 here).
Similar thing happens if submodule.diff is "diff".
Do like it's done in grep.c when calling fill_filespec() and force it to
be recognized as a file by adding S_IFREG to the mode.
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git format-patch" learned a new "--range-diff" option to explain
the difference between this version and the previous attempt in
the cover letter (or after the tree-dashes as a comment).
* es/format-patch-rangediff:
format-patch: allow --range-diff to apply to a lone-patch
format-patch: add --creation-factor tweak for --range-diff
format-patch: teach --range-diff to respect -v/--reroll-count
format-patch: extend --range-diff to accept revision range
format-patch: add --range-diff option to embed diff in cover letter
range-diff: relieve callers of low-level configuration burden
range-diff: publish default creation factor
range-diff: respect diff_option.file rather than assuming 'stdout'
The range-diff coloring is a bit fuzzy when it comes to special lines of
a diff, such as indicating new and old files with +++ and ---, as it
would pickup the first character and interpret it for its coloring, which
seems annoying as in regular diffs, these lines are colored bold via
DIFF_METAINFO.
By indenting these lines by a white space, they will be treated as context
which is much more useful, an example [1] on the range diff series itself:
[...]
+ diff --git a/Documentation/git-range-diff.txt b/Documentation/git-range-diff.txt
+ new file mode 100644
+ --- /dev/null
+ +++ b/Documentation/git-range-diff.txt
+@@
++git-range-diff(1)
[...]
+
diff --git a/Makefile b/Makefile
--- a/Makefile
+++ b/Makefile
[...]
The first lines that introduce the new file for the man page will have the
'+' sign colored and the rest of the line will be bold.
The later lines that indicate a change to the Makefile will be treated as
context both in the outer and inner diff, such that those lines stay
regular color.
[1] ./git-range-diff pr-1/dscho/branch-diff-v3...pr-1/dscho/branch-diff-v4
These tags are found at https://github.com/gitgitgadget/git
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This change itself only changes the internal communication and should
have no visible effect to the user. We instruct the diff code that
produces the inner diffs to use other markers instead of the
usual markers for new, old and context lines.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There are a number of very low-level configuration details which need to
be managed precisely to generate a proper range-diff. In particular,
'diff_options' output format, header suppression, indentation, and
dual-color mode must all be set appropriately to ensure proper behavior.
Handle these details locally in the libified range-diff back-end rather
than forcing each caller to have specialized knowledge of these
implementation details, and to avoid duplication as new callers are
added.
While at it, localize these tweaks to be active only while generating
the range-diff, so they don't clobber the caller-provided
'diff_options', which might be used beyond range-diff generation.
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The actual diffs output by range-diff respect diff_option.file, which
range-diff passes down the call-chain, thus are destination-agnostic.
However, output_pair_header() is hard-coded to emit to 'stdout'. Fix
this by making output_pair_header() respect diff_option.file, as well.
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
As pointed out by Elijah Newren, tbdiff has this neat little alignment
trick where it outputs the commit pairs with patch numbers that are
padded to the maximal patch number's width:
1: cafedead = 1: acefade first patch
[...]
314: beefeada < 314: facecab up to PI!
Let's do the same in range-diff, too.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Arguably the most important part of `git range-diff`'s output is the
list of commits in the two branches, together with their relationships.
For that reason, tbdiff introduced color-coding that is pretty
intuitive, especially for unchanged patches (all dim yellow, like the
first line in `git show`'s output) vs modified patches (old commit is
red, new commit is green). Let's imitate that color scheme.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We are comparing complete, formatted commit messages with patches. There
are no function names here, so stop looking for them.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This not only uses "dashed stand-ins" for "pairs" where one side is
missing (i.e. unmatched commits that are present only in one of the two
commit ranges), but also adds onelines for the reader's pleasure.
This change brings `git range-diff` yet another step closer to
feature parity with tbdiff: it now shows the oneline, too, and indicates
with `=` when the commits have identical diffs.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When comparing commit messages, we need to keep in mind that they are
indented by four spaces. That is, empty lines are no longer empty, but
have "trailing whitespace". When displaying them in color, that results
in those nagging red lines.
Let's just right-trim the lines in the commit message, it's not like
trailing white-space in the commit messages are important enough to care
about in `git range-diff`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Just like tbdiff, we now show the diff between matching patches. This is
a "diff of two diffs", so it can be a bit daunting to read for the
beginner.
An alternative would be to display an interdiff, i.e. the hypothetical
diff which is the result of first reverting the old diff and then
applying the new diff.
Especially when rebasing frequently, an interdiff is often not feasible,
though: if the old diff cannot be applied in reverse (due to a moving
upstream), an interdiff can simply not be inferred.
This commit brings `range-diff` closer to feature parity with regard
to tbdiff.
To make `git range-diff` respect e.g. color.diff.* settings, we have
to adjust git_branch_config() accordingly.
Note: while we now parse diff options such as --color, the effect is not
yet the same as in tbdiff, where also the commit pairs would be colored.
This is left for a later commit.
Note also: while tbdiff accepts the `--no-patches` option to suppress
these diffs between patches, we prefer the `-s` (or `--no-patch`) option
that is automatically supported via our use of diff_opt_parse().
And finally note: to support diff options, we have to call
`parse_options()` such that it keeps unknown options, and then loop over
those and let `diff_opt_parse()` handle them. After that loop, we have
to call `parse_options()` again, to make sure that no unknown options
are left.
Helped-by: Thomas Gummerer <t.gummerer@gmail.com>
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This patch lets `git range-diff` use the same order as tbdiff.
The idea is simple: for left-to-right readers, it is natural to assume
that the `git range-diff` is performed between an older vs a newer
version of the branch. As such, the user is probably more interested in
the question "where did this come from?" rather than "where did that one
go?".
To that end, we list the commits in the order of the second commit range
("the newer version"), inserting the unmatched commits of the first
commit range as soon as all their predecessors have been shown.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
At this stage, `git range-diff` can determine corresponding commits
of two related commit ranges. This makes use of the recently introduced
implementation of the linear assignment algorithm.
The core of this patch is a straight port of the ideas of tbdiff, the
apparently dormant project at https://github.com/trast/tbdiff.
The output does not at all match `tbdiff`'s output yet, as this patch
really concentrates on getting the patch matching part right.
Note: due to differences in the diff algorithm (`tbdiff` uses the Python
module `difflib`, Git uses its xdiff fork), the cost matrix calculated
by `range-diff` is different (but very similar) to the one calculated
by `tbdiff`. Therefore, it is possible that they find different matching
commits in corner cases (e.g. when a patch was split into two patches of
roughly equal length).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>