The Perl version of `git add -p` supports this config setting to allow
users to input commands via single characters (as opposed to having to
press the <Enter> key afterwards).
This is an opt-in feature because it requires Perl packages
(Term::ReadKey and Term::Cap, where it tries to handle an absence of the
latter package gracefully) to work. Note that at least on Ubuntu, that
Perl package is not installed by default (it needs to be installed via
`sudo apt-get install libterm-readkey-perl`), so this feature is
probably not used a whole lot.
In C, we obviously do not have these packages available, but we just
introduced `read_single_keystroke()` that is similar to what
Term::ReadKey provides, and we use that here.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The Perl version of `git add -p` reads the config setting
`diff.algorithm` and if set, uses it to generate the diff using the
specified algorithm.
This patch ports that functionality to the C version.
To make sure that this works as intended, we add a regression test case
that tries to specify a bogus diff algorithm and then verifies that `git
diff-files` produced the expected error message.
Note: In that new test case, we actually ignore the exit code of `git
add -p`. The reason is that the C version exits with failure (as one
might expect), but the Perl version does not.
In fact, the Perl version continues happily after the uncolored diff
failed, trying to generate the colored diff, still not catching the
problem, and then it pretends to have succeeded (with exit code 0).
This is arguably a bug in the Perl version, and fixing it is safely
outside the scope of this patch.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The Perl version supports post-processing the colored diff (that is
generated in addition to the uncolored diff, intended to offer a
prettier user experience) by a command configured via that config
setting, and now the built-in version does that, too.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This is a straight-forward port of 2f0896ec3a (restore: support
--patch, 2019-04-25) which added support for `git restore -p`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This patch teaches the built-in `git add -p` machinery all the tricks it
needs to know in order to act as the work horse for `git checkout -p`.
Apart from the minor changes (slightly reworded messages, different
`diff` and `apply --check` invocations), it requires a new function to
actually apply the changes, as `git checkout -p` is a bit special in
that respect: when the desired changes do not apply to the index, but
apply to the work tree, Git does not fail straight away, but asks the
user whether to apply the changes to the worktree at least.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The `git stash` and `git reset` commands support a `--patch` option, and
both simply hand off to `git add -p` to perform that work. Let's teach
the built-in version of that command to be able to perform that work, too.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The Perl script backing `git add -p` is used not only for that command,
but also for `git stash -p`, `git reset -p` and `git checkout -p`.
In preparation for teaching the C version of `git add -p` to support
also the latter commands, let's abstract away what is "stage" specific
into a dedicated data structure describing the differences between the
patch modes.
Finally, please note that the Perl version tries to make sure that the
diffs are only generated for the modified files. This is not actually
necessary, as the calls to Git's diff machinery already perform that
work, and perform it well. This makes it unnecessary to port the
`FILTER` field of the `%patch_modes` struct, as well as the
`get_diff_reference()` function.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Just like `git add --edit` allows the user to edit the diff before it is
being applied to the index, this feature allows the user to edit the
diff *hunk*.
Naturally, it gets a bit more complicated here because the result has
to play well with the remaining hunks of the overall diff. Therefore,
we have to do a loop in which we let the user edit the hunk, then test
whether the result would work, and if not, drop the edits and let the
user decide whether to try editing the hunk again.
Note: in contrast to the Perl version, we use the same diff
"coalescing" (i.e. merging overlapping hunks into a single one) also for
the check after editing, and we introduce a new flag for that purpose
that asks the `reassemble_patch()` function to pretend that all hunks
were selected for use.
This allows us to continue to run `git apply` *without* the
`--allow-overlap` option (unlike the Perl version), and it also fixes
two known breakages in `t3701-add-interactive.sh` (which we cannot mark
as resolved so far because the Perl script version is still the default
and continues to have those breakages).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When skipping a hunk that adds a different number of lines than it
removes, we need to adjust the subsequent hunk headers of non-skipped
hunks: in pathological cases, the context is not enough to determine
precisely where the patch should be applied.
This problem was identified in 23fea4c240 (t3701: add failing test for
pathological context lines, 2018-03-01) and fixed in the Perl version in
fecc6f3a68 (add -p: adjust offsets of subsequent hunks when one is
skipped, 2018-03-01).
And this patch fixes it in the C version of `git add -p`.
In contrast to the Perl version, we try to keep the extra text on the
hunk header (which typically contains the signature of the function
whose code is changed in the hunk) intact.
Note: while the C version does not support staging mode changes at this
stage, we already prepare for this by simply skipping the hunk header if
both old and new offset is 0 (this cannot happen for regular hunks, and
we will use this as an indicator that we are looking at a special hunk).
Likewise, we already prepare for hunk splitting by handling the absence
of extra text in the hunk header gracefully: only the first split hunk
will have that text, the others will not (indicated by an empty extra
text start/end range). Preparing for hunk splitting already at this
stage avoids an indentation change of the entire hunk header-printing
block later, and is almost as easy to review as without that handling.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In the previous steps, we re-implemented the main loop of `git add -i`
in C, and most of the commands.
Notably, we left out the actual functionality of `patch`, as the
relevant code makes up more than half of `git-add--interactive.perl`,
and is actually pretty independent of the rest of the commands.
With this commit, we start to tackle that `patch` part. For better
separation of concerns, we keep the code in a separate file,
`add-patch.c`. The new code is still guarded behind the
`add.interactive.useBuiltin` config setting, and for the moment,
it can only be called via `git add -p`.
The actual functionality follows the original implementation of
5cde71d64a (git-add --interactive, 2006-12-10), but not too closely
(for example, we use string offsets rather than copying strings around,
and after seeing whether the `k` and `j` commands are applicable, in the
C version we remember which previous/next hunk was undecided, and use it
rather than looking again when the user asked to jump).
As a further deviation from that commit, We also use a comma instead of
a slash to separate the available commands in the prompt, as the current
version of the Perl script does this, and we also add a line about the
question mark ("print help") to the help text.
While it is tempting to use this conversion of `git add -p` as an excuse
to work on `apply_all_patches()` so that it does _not_ want to read a
file from `stdin` or from a file, but accepts, say, an `strbuf` instead,
we will refrain from this particular rabbit hole at this stage.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Unlike previous conversions to C, where we started with a built-in
helper, we start this conversion by adding an interception in the
`run_add_interactive()` function when the new opt-in
`add.interactive.useBuiltin` config knob is turned on (or the
corresponding environment variable `GIT_TEST_ADD_I_USE_BUILTIN`), and
calling the new internal API function `run_add_i()` that is implemented
directly in libgit.a.
At this point, the built-in version of `git add -i` only states that it
cannot do anything yet. In subsequent patches/patch series, the
`run_add_i()` function will gain more and more functionality, until it
is feature complete. The whole arc of the conversion can be found in the
PRs #170-175 at https://github.com/gitgitgadget/git.
The "--helper approach" can unfortunately not be used here: on Windows
we face the very specific problem that a `system()` call in
Perl seems to close `stdin` in the parent process when the spawned
process consumes even one character from `stdin`. Which prevents us from
implementing the main loop in C and still trying to hand off to the Perl
script.
The very real downside of the approach we have to take here is that the
test suite won't pass with `GIT_TEST_ADD_I_USE_BUILTIN=true` until the
conversion is complete (the `--helper` approach would have let it pass,
even at each of the incremental conversion steps).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Johannes Schindelin