Commit Graph

25 Commits

Author SHA1 Message Date
Johannes Schindelin
08d383f23e interactive: refactor code asking the user for interactive input
There are quite a few code locations (e.g. `git clean --interactive`)
where Git asks the user for an answer. In preparation for fixing a bug
shared by all of them, and also to DRY up the code, let's refactor it.

Please note that most of these callers trimmed white-space both at the
beginning and at the end of the answer, instead of trimming only the
end (as the caller in `add-patch.c` does).

Therefore, technically speaking, we change behavior in this patch. At
the same time, it can be argued that this is actually a bug fix.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-10 10:26:31 -07:00
Johannes Schindelin
04f816b125 built-in add -p: respect the interactive.singlekey config setting
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>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-01-15 12:06:17 -08:00
Johannes Schindelin
08b1ea4c39 built-in add -p: handle diff.algorithm
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.

Note: just like `git-add--interactive.perl`, we do _not_ respect this
config setting in `git add -i`'s `diff` command, but _only_ in the
`patch` command.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-01-15 12:06:16 -08:00
Johannes Schindelin
180f48df69 built-in add -p: support interactive.diffFilter
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>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-01-15 12:06:16 -08:00
Johannes Schindelin
cee6cb7300 built-in add -p: implement the "worktree" patch modes
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>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-12-21 16:06:22 -08:00
Johannes Schindelin
52628f94fc built-in add -p: implement the "checkout" patch modes
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>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-12-21 16:06:22 -08:00
Johannes Schindelin
36bae1dc0e built-in add -p: implement the "stash" and "reset" patch modes
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>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-12-21 16:06:21 -08:00
Johannes Schindelin
d2a233cb8b built-in add -p: prepare for patch modes other than "stage"
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>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-12-21 16:06:21 -08:00
Johannes Schindelin
2e4083198d built-in add -p: show helpful hint when nothing can be staged
This patch will make `git add -p` show "No changes." or "Only binary
files changed." in that case.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-12-13 12:37:14 -08:00
Johannes Schindelin
54d9d9b2ee built-in add -p: only show the applicable parts of the help text
When displaying the only hunk in a file's diff, the prompt already
excludes the commands to navigate to the previous/next hunk.

Let's also let the `?` command show only the help lines corresponding to
the commands that are displayed in the prompt.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-12-13 12:37:14 -08:00
Johannes Schindelin
ade246efed built-in add -p: implement the 'q' ("quit") command
This command is actually very similar to the 'd' ("do not stage this
hunk or any of the later hunks in the file") command: it just does
something on top, namely leave the loop and return a value indicating
that we're quittin'.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-12-13 12:37:14 -08:00
Johannes Schindelin
d6cf873340 built-in add -p: implement the '/' ("search regex") command
This patch implements the hunk searching feature in the C version of
`git add -p`.

A test is added to verify that this behavior matches the one of the Perl
version of `git add -p`.

Note that this involves a change of behavior: the Perl version uses (of
course) the Perl flavor of regular expressions, while this patch uses
the regcomp()/regexec(), i.e. POSIX extended regular expressions. In
practice, this behavior change is unlikely to matter.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-12-13 12:37:14 -08:00
Johannes Schindelin
9254bdfb4f built-in add -p: implement the 'g' ("goto") command
With this patch, it is now possible to see a summary of the available
hunks and to navigate between them (by number).

A test is added to verify that this behavior matches the one of the Perl
version of `git add -p`.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-12-13 12:37:14 -08:00
Johannes Schindelin
bcdd297b78 built-in add -p: implement hunk editing
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>
2019-12-13 12:37:14 -08:00
Johannes Schindelin
11f2c0dae8 built-in add -p: coalesce hunks after splitting them
This is considered "the right thing to do", according to 933e44d3a0
("add -p": work-around an old laziness that does not coalesce hunks,
2011-04-06).

Note: we cannot simply modify the hunks while merging them; Once we
implement hunk editing, we will call `reassemble_patch()` whenever a
hunk is edited, therefore we must not modify the hunks (because the user
might e.g. hit `K` and change their mind whether to stage the previous
hunk).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-12-13 12:37:14 -08:00
Johannes Schindelin
510aeca199 built-in add -p: implement the hunk splitting feature
If this developer's workflow is any indication, then this is *the* most
useful feature of Git's interactive `add `command.

Note: once again, this is not a verbatim conversion from the Perl code
to C: the `hunk_splittable()` function, for example, essentially did all
the work of splitting the hunk, just to find out whether more than one
hunk would have been the result (and then tossed that result into the
trash). In C we instead count the number of resulting hunks (without
actually doing the work of splitting, but just counting the transitions
from non-context lines to context lines), and store that information
with the hunk, and we do that *while* parsing the diff in the first
place.

Another deviation: the built-in `git add -p` was designed with a single
strbuf holding the diff (and another one holding the colored diff, if
that one was asked for) in mind, and hunks essentially store just the
start and end offsets pointing into that strbuf. As a consequence, when
we split hunks, we now use a special mode where the hunk header is
generated dynamically, and only the rest of the hunk is stored using
such start/end offsets. This way, we also avoid the frequent
formatting/re-parsing of the hunk header of the Perl version.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-12-13 12:37:14 -08:00
Johannes Schindelin
0ecd9d27fc built-in add -p: show different prompts for mode changes and deletions
Just like the Perl version, we now helpfully ask the user whether they
want to stage a mode change, or a deletion.

Note that we define the prompts in an array, in preparation for a later
patch that changes those prompts to yet different versions for `git
reset -p`, `git stash -p` and `git checkout -p` (which all call the `git
add -p` machinery to do the actual work).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-12-13 12:37:14 -08:00
Johannes Schindelin
5906d5de77 built-in app -p: allow selecting a mode change as a "hunk"
This imitates the way the Perl version treats mode changes: it offers
the mode change up for the user to decide, as if it was a diff hunk.

In contrast to the Perl version, we make use of the fact that the mode
line is the first hunk, and explicitly strip out that line from the diff
header if that "hunk" was not selected to be applied, and skipping that
hunk while coalescing the diff. The Perl version plays some kind of diff
line lego instead.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-12-13 12:37:14 -08:00
Johannes Schindelin
47dc4fd5eb built-in add -p: handle deleted empty files
This addresses the same problem as 24ab81ae4d (add-interactive: handle
deletion of empty files, 2009-10-27), although in a different way: we
not only stick the "deleted file" line into its own pseudo hunk, but
also the entire remainder (if any) of the same diff.

That way, we do not have to play any funny games with regards to
coalescing the diff after the user selected what (possibly pseudo-)hunks
to stage.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-12-13 12:37:13 -08:00
Johannes Schindelin
80399aec5a built-in add -p: support multi-file diffs
For simplicity, the initial implementation in C handled only a single
modified file. Now it handles an arbitrary number of files.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-12-13 12:37:13 -08:00
Johannes Schindelin
7584dd3c66 built-in add -p: offer a helpful error message when hunk navigation failed
... just like the Perl version currently does...

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-12-13 12:37:13 -08:00
Johannes Schindelin
12c24cf850 built-in add -p: color the prompt and the help text
... just like the Perl version ;-)

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-12-13 12:37:13 -08:00
Johannes Schindelin
25ea47af49 built-in add -p: adjust hunk headers as needed
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>
2019-12-13 12:37:13 -08:00
Johannes Schindelin
e3bd11b4eb built-in add -p: show colored hunks by default
Just like the Perl version, we now generate two diffs if `color.diff` is
set: one with and one without color. Then we parse them in parallel and
record which hunks start at which offsets in both.

Note that this is a (slight) deviation from the way the Perl version did
it: we are no longer reading the output of `diff-files` line by line
(which is more natural for Perl than for C), but in one go, and parse
everything later, so we might just as well do it in synchrony.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-12-13 12:37:13 -08:00
Johannes Schindelin
f6aa7ecc34 built-in add -i: start implementing the patch functionality in C
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>
2019-12-13 12:37:13 -08:00