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>
