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2020-09-22Merge branch 'pw/add-p-edit-ita-path'Libravatar Junio C Hamano1-61/+79
"add -p" now allows editing paths that were only added in intent. * pw/add-p-edit-ita-path: add -p: fix editing of intent-to-add paths
2020-09-18Merge branch 'jk/add-i-fixes'Libravatar Junio C Hamano1-1/+1
"add -i/-p" fixes. * jk/add-i-fixes: add--interactive.perl: specify --no-color explicitly add-patch: fix inverted return code of repo_read_index()
2020-09-18Merge branch 'pw/add-p-leakfix'Libravatar Junio C Hamano1-8/+16
Leakfix. * pw/add-p-leakfix: add -p: fix memory leak
2020-09-09add -p: fix editing of intent-to-add pathsLibravatar Phillip Wood1-61/+79
A popular way of partially staging a new file is to run `git add -N <path>` and then use the hunk editing of `git add -p` to select the part of the file that the user wishes to stage. Since 85953a3187 ("diff-files --raw: show correct post-image of intent-to-add files", 2020-07-01) this has stopped working as intent-to-add paths are now show as new files rather than changes to an empty blob and `git apply` refused to apply a creation patch for a path that was marked as intent-to-add. 7cfde3fa0f ("apply: allow "new file" patches on i-t-a entries", 2020-08-06) fixed the problem with apply but it still wasn't possible to edit the added hunk properly. 2c8bd8471a ("checkout -p: handle new files correctly", 2020-05-27) had previously changed `add -p` to handle new files but it did not implement patch editing correctly. The perl version simply forbade editing and the C version opened the editor with the full diff rather that just the hunk which meant that the user had to edit the hunk header manually to get it to work. The root cause of the problem is that added files store the diff header with the hunk data rather than separating the two as we do for other changes. Changing added files to store the diff header separately fixes the editing problem at the expense of having to special case empty additions as they no longer have any hunks associated with them, only the diff header. The changes move some existing code into a conditional changing the indentation, they are best viewed with --color-moved-ws=allow-indentation-change (or --ignore-space-change works well to get an overview of the changes) Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk> Reported-by: Thomas Sullivan <tom@msbit.com.au> Reported-by: Yuchen Ying <ych@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-08add -p: fix memory leakLibravatar Phillip Wood1-8/+16
asan reports that the C version of `add -p` is not freeing all the memory it allocates. Fix this by introducing a function to clear `struct add_p_state` and use it instead of freeing individual members. Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk> Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-08add-patch: fix inverted return code of repo_read_index()Libravatar Jeff King1-1/+1
After applying hunks to a file with "add -p", the C patch_update_file() function tries to refresh the index (just like the perl version does). We can only refresh the index if we're able to read it in, so we first check the return value of repo_read_index(). But unlike many functions, where "0" is success, that function is documented to return the number of entries in the index. Hence we should be checking for success with a non-negative return value. Neither the tests nor any users seem to have noticed this, probably due to a combination of: - this affects only the C version, which is not yet the default - following it up with any porcelain command like "git diff" or "git commit" would refresh the index automatically. But you can see the problem by running the plumbing "git diff-files" immediately after "add -p" stages all hunks. Running the new test with GIT_TEST_ADD_I_USE_BUILTIN=1 fails without the matching code change. Signed-off-by: Jeff King <peff@peff.net> Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-03Merge branch 'pw/add-p-allowed-options-fix'Libravatar Junio C Hamano1-25/+42
"git add -p" update. * pw/add-p-allowed-options-fix: add -p: fix checking of user input add -p: use ALLOC_GROW_BY instead of ALLOW_GROW
2020-08-17add -p: fix checking of user inputLibravatar Phillip Wood1-16/+38
When a file has been deleted the C version of add -p allows the user to edit a hunk even though 'e' is not in the list of allowed responses. (I think 'e' is disallowed because if the file is edited it is no longer a deletion and we're not set up to rewrite the diff header). The invalid response was allowed because the test that determines whether to display 'e' was not duplicated correctly in the code that processes the user's choice. Fix this by using flags that are set when constructing the prompt and checked when processing the user's choice rather than repeating the check itself. Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-17add -p: use ALLOC_GROW_BY instead of ALLOW_GROWLibravatar Phillip Wood1-9/+4
This simplifies the code slightly, especially the third case where hunk_nr was incremented a few lines before ALLOC_GROW(). Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-10Merge branch 'jk/strvec'Libravatar Junio C Hamano1-24/+24
The argv_array API is useful for not just managing argv but any "vector" (NULL-terminated array) of strings, and has seen adoption to a certain degree. It has been renamed to "strvec" to reduce the barrier to adoption. * jk/strvec: strvec: rename struct fields strvec: drop argv_array compatibility layer strvec: update documention to avoid argv_array strvec: fix indentation in renamed calls strvec: convert remaining callers away from argv_array name strvec: convert more callers away from argv_array name strvec: convert builtin/ callers away from argv_array name quote: rename sq_dequote_to_argv_array to mention strvec strvec: rename files from argv-array to strvec argv-array: rename to strvec argv-array: use size_t for count and alloc
2020-07-30strvec: rename struct fieldsLibravatar Jeff King1-4/+4
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>
2020-07-29comment: fix spelling mistakes inside commentsLibravatar Steve Kemp1-1/+1
This commit fixes a couple of minor spelling mistakes inside comments. Signed-off-by: Steve Kemp <steve@steve.org.uk> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-07-28strvec: fix indentation in renamed callsLibravatar Jeff King1-5/+5
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>
2020-07-28strvec: convert more callers away from argv_array nameLibravatar Jeff King1-14/+14
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 remaining files from the first half of the alphabet, to keep the diff to a manageable size. 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; ' and then selectively staging files with "git add '[abcdefghjkl]*'". 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>
2020-07-28strvec: rename files from argv-array to strvecLibravatar Jeff King1-1/+1
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>
2020-06-08Merge branch 'js/checkout-p-new-file'Libravatar Junio C Hamano1-7/+23
"git checkout -p" did not handle a newly added path at all. * js/checkout-p-new-file: checkout -p: handle new files correctly
2020-05-27checkout -p: handle new files correctlyLibravatar Johannes Schindelin1-7/+23
The original patch selection code was written for `git add -p`, and the fundamental unit on which it works is a hunk. We hacked around that to handle deletions back in 24ab81ae4d (add-interactive: handle deletion of empty files, 2009-10-27). But `git add -p` would never see a new file, since we only consider the set of tracked files in the index. However, since the same machinery was used for `git checkout -p` & friends, we can see new files. Handle this case specifically, adding a new prompt for it that is modeled after the `deleted file` case. This also fixes the problem where added _empty_ files could not be staged via `git checkout -p`. Reported-by: Merlin Büge <toni@bluenox07.de> Helped-by: Jeff King <peff@peff.net> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-10interactive: refactor code asking the user for interactive inputLibravatar Johannes Schindelin1-2/+2
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>
2020-01-15built-in add -p: respect the `interactive.singlekey` config settingLibravatar Johannes Schindelin1-4/+17
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>
2020-01-15built-in add -p: handle diff.algorithmLibravatar Johannes Schindelin1-0/+3
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>
2020-01-15built-in add -p: support interactive.diffFilterLibravatar Johannes Schindelin1-0/+33
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>
2019-12-21built-in add -p: implement the "worktree" patch modesLibravatar Johannes Schindelin1-0/+50
This is a straight-forward port of 2f0896ec3ad4 (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>
2019-12-21built-in add -p: implement the "checkout" patch modesLibravatar Johannes Schindelin1-5/+133
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>
2019-12-21built-in add -p: implement the "stash" and "reset" patch modesLibravatar Johannes Schindelin1-4/+79
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>
2019-12-21built-in add -p: prepare for patch modes other than "stage"Libravatar Johannes Schindelin1-26/+69
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>
2019-12-13built-in add -p: show helpful hint when nothing can be stagedLibravatar Johannes Schindelin1-4/+13
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>
2019-12-13built-in add -p: only show the applicable parts of the help textLibravatar Johannes Schindelin1-4/+28
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>
2019-12-13built-in add -p: implement the 'q' ("quit") commandLibravatar Johannes Schindelin1-6/+11
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>
2019-12-13built-in add -p: implement the '/' ("search regex") commandLibravatar Johannes Schindelin1-1/+49
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>
2019-12-13built-in add -p: implement the 'g' ("goto") commandLibravatar Johannes Schindelin1-0/+88
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>
2019-12-13built-in add -p: implement hunk editingLibravatar Johannes Schindelin1-17/+316
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>
2019-12-13built-in add -p: coalesce hunks after splitting themLibravatar Johannes Schindelin1-1/+57
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>
2019-12-13built-in add -p: implement the hunk splitting featureLibravatar Johannes Schindelin1-2/+213
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>
2019-12-13built-in add -p: show different prompts for mode changes and deletionsLibravatar Johannes Schindelin1-2/+20
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>
2019-12-13built-in app -p: allow selecting a mode change as a "hunk"Libravatar Johannes Schindelin1-5/+104
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>
2019-12-13built-in add -p: handle deleted empty filesLibravatar Johannes Schindelin1-2/+11
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>
2019-12-13built-in add -p: support multi-file diffsLibravatar Johannes Schindelin1-38/+53
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>
2019-12-13built-in add -p: offer a helpful error message when hunk navigation failedLibravatar Johannes Schindelin1-11/+33
... 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>
2019-12-13built-in add -p: color the prompt and the help textLibravatar Johannes Schindelin1-4/+8
... just like the Perl version ;-) Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-12-13built-in add -p: adjust hunk headers as neededLibravatar Johannes Schindelin1-12/+133
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>
2019-12-13built-in add -p: show colored hunks by defaultLibravatar Johannes Schindelin1-17/+62
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>
2019-12-13built-in add -i: start implementing the `patch` functionality in CLibravatar Johannes Schindelin1-0/+265
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 5cde71d64aff (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>