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@NinjaInShade NinjaInShade commented May 4, 2025

This series of patches attempt to give --interactive/--patch compatible builtins ("add", "commit", "checkout", "reset", "restore" and "stash") better support and nicer experience for configuring how many context lines are shown in diffs through a variety of ways.

Prior to these patches, the user could not choose how many context lines they saw in --patch commands (apart from one workaround by using GIT_DIFF_OPTS=-u<number> ..., however this isn't a good user experience or a persistent solution). Additionally, the behaviour around reading from the diff.context and diff.interHunkContext configs was also inconsistent with other diff generating commands such as "log -p".

The summarised changes below hopefully make this experience better and fix some inconsistencies:

  • diff.context and diff.interHunkContext configs are now respected by --patch compatible commands
  • --unified and --inter-hunk-context command line options have been added to --patch compatible commands (which take prescendence over file configs)
  • "add" and "commit" in --interactive mode now expose a new "context" subcommand which configures the amount of context lines you wish to see in subsequent diffs generated from other subcommands such as "patch" or "diff"

The original discussion for this can be read at:

Changes since v1:

  • Update commit descriptions
  • Update tests to use the more modern and robust test_grep and test_config utils
  • Reword some documentation / user messages
  • Ensure each commit is atomic and builds/passes tests on it's own
  • Make new command line options DRY
  • Add tests for interhunk context interaction
  • Error if context config/command line options are negative
  • Drop previous last commit to do with new subcommand for --interactive add/commit. My motivations behind this patch series originally where quite simple, just for add-patch commands to respect context configs. This subcommand, after the discussion in v1, will require more thought and a larger implementation that what I had anticipated. I would prefer to leave this for another time as it's the least impactful but the most time intensive and complicated idea.

cc: "Kristoffer Haugsbakk" [email protected]
cc: Eric Sunshine [email protected]
cc: Christian Couder [email protected]
cc: Phillip Wood [email protected]

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@NinjaInShade NinjaInShade changed the title Increased --unified support for --patch commands Better support for customising context lines in --patch commands May 5, 2025
@NinjaInShade NinjaInShade force-pushed the interactive-patch-context branch 2 times, most recently from 9b90dc6 to b4b7854 Compare May 5, 2025 07:37
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Submitted as [email protected]

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@NinjaInShade NinjaInShade force-pushed the interactive-patch-context branch from b4b7854 to cf726da Compare May 10, 2025 12:40
Refactor to use the modern "test_grep" test utility instead of regular
"grep" which provides better debug information if tests fail.

This is a prerequisite to the commits that follow which add to both test
files.

Signed-off-by: Leon Michalak <[email protected]>
Refactor to use the modern "test_config" test utility instead of manual
"git config" as the former provides clean up on test completion.

This is a prerequisite to the commits that follow which add to this test
file.

Signed-off-by: Leon Michalak <[email protected]>
Various builtins that use add-patch infrastructure do not respect
the user's diff.context and diff.interHunkContext file configurations.
This patch fixes this inconsistency.

Signed-off-by: Leon Michalak <[email protected]>
This patch compliments the previous commit, where builtins that use
add-patch infrastructure now respect diff.context and
diff.interHunkContext file configurations.

In particular, this patch helps users who don't want to set persistent
context configurations or just want a way to override them on a one-time
basis, by allowing the relevant builtins to accept corresponding command
line options that override the file configurations.

This mimics commands such as diff and log, which allow for both context
file configuration and command line overrides.

Signed-off-by: Leon Michalak <[email protected]>
@NinjaInShade NinjaInShade force-pushed the interactive-patch-context branch from cf726da to 973dfad Compare May 10, 2025 12:41
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To fetch this version into FETCH_HEAD:

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To fetch this version to local tag pr-1915/NinjaInShade/interactive-patch-context-v2:

git fetch --no-tags https://github.com/gitgitgadget/git/ tag pr-1915/NinjaInShade/interactive-patch-context-v2

@@ -63,7 +63,7 @@ test_expect_success 'setup (initial)' '
'
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On the Git mailing list, Junio C Hamano wrote (reply to this):

"Leon Michalak via GitGitGadget" <[email protected]> writes:

> From: Leon Michalak <[email protected]>
>
> Refactor to use the modern "test_grep" test utility instead of regular
> "grep" which provides better debug information if tests fail.
>
> This is a prerequisite to the commits that follow which add to both test
> files.
>
> Signed-off-by: Leon Michalak <[email protected]>
> ---

These mostly look sensible, but I would title & phrase the commit
description to 'use "test_grep"', not 'refactor to &'.  It's shorter
and more direct ;-)

Thanks.

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On the Git mailing list, Leon Michalak wrote (reply to this):

On Mon, 12 May 2025 at 14:42, Junio C Hamano <[email protected]> wrote:
> These mostly look sensible, but I would title & phrase the commit
> description to 'use "test_grep"', not 'refactor to &'.  It's shorter
> and more direct ;-)

Thanks - will make sure to change that in v3 :)

@@ -0,0 +1,10 @@
`-U<n>`::
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On the Git mailing list, Junio C Hamano wrote (reply to this):

"Leon Michalak via GitGitGadget" <[email protected]> writes:

> diff --git a/Documentation/diff-context-options.adoc b/Documentation/diff-context-options.adoc
> new file mode 100644
> index 000000000000..e161260358ff
> --- /dev/null
> +++ b/Documentation/diff-context-options.adoc
> @@ -0,0 +1,10 @@
> +`-U<n>`::
> +`--unified=<n>`::
> +	Generate diffs with _<n>_ lines of context. Defaults to `diff.context`
> +	or 3 if the config option is unset.
> +
> +`--inter-hunk-context=<n>`::
> +	Show the context between diff hunks, up to the specified _<number>_
> +	of lines, thereby fusing hunks that are close to each other.
> +	Defaults to `diff.interHunkContext` or 0 if the config option
> +	is unset.

It might not be trivial to do but I wonder if we cannot do better
than this to share more of the same text across manual pages.  These
two being options understood by `git diff`, we certainly have an
existing description for them, no?

Other than that, looking good to me.

Thanks.

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On the Git mailing list, Leon Michalak wrote (reply to this):

On Mon, 12 May 2025 at 17:45, Junio C Hamano <[email protected]> wrote:
> It might not be trivial to do but I wonder if we cannot do better
> than this to share more of the same text across manual pages.  These
> two being options understood by `git diff`, we certainly have an
> existing description for them, no?

Yes, I did of course notice documentation for `git diff` also has
these; ultimately my justification for not changing that to use this
new .adoc include as well was for a couple reasons:
- these two options are not together in the `git diff` documentation
(not *so* important, and they probably should actually be together?)
- there is an extra if def which adds on "implies --patch" text in the
`git diff` documentation which isn't the behaviour the add-patch
commands are going for, so that makes the intent a little different
here

But would be good to hear if anyone else has any thoughts.

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gitgitgadget bot commented May 12, 2025

This patch series was integrated into seen via git@0945e76.

@gitgitgadget gitgitgadget bot added the seen label May 12, 2025
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gitgitgadget bot commented May 12, 2025

This patch series was integrated into seen via git@3512d8e.

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gitgitgadget bot commented May 13, 2025

This patch series was integrated into seen via git@d808817.

@@ -39,8 +39,12 @@ static void init_color(struct repository *r, struct add_i_state *s,
void init_add_i_state(struct add_i_state *s, struct repository *r)
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On the Git mailing list, Phillip Wood wrote (reply to this):

Hi Leon

On 10/05/2025 14:46, Leon Michalak via GitGitGadget wrote:
> From: Leon Michalak <[email protected]>
> > Various builtins that use add-patch infrastructure do not respect
> the user's diff.context and diff.interHunkContext file configurations.

We could expand this slightly by adding

This is because the plumbing commands used by "git add -p" to generate
the diff do not read those config settings. Fix this by reading the
config before generating the patch and passing it along to the diff
command with the "-U" and "--inter-hunk-context" command-line options.

> This patch fixes this inconsistency.
> > Signed-off-by: Leon Michalak <[email protected]>
> ---

> @@ -78,6 +82,19 @@ void init_add_i_state(struct add_i_state *s, struct repository *r)
>   	repo_config_get_string(r, "diff.algorithm",
>   			       &s->interactive_diff_algorithm);
>   > +	if (!repo_config_get_int(r, "diff.context", &context)) {
> +		if (context < 0)
> +			die(_("%s cannot be negative"), "diff.context");
> +		else
> +			s->context = context;
> +	};
> +	if (!repo_config_get_int(r, "diff.interHunkContext", &interhunkcontext)) {
> +		if (interhunkcontext < 0)
> +			die(_("%s cannot be negative"), "diff.interHunkContext");
> +		else
> +			s->interhunkcontext = interhunkcontext;
> +	};

Thanks for changing this. This iteration of the code changes looks good

> diff --git a/t/t4055-diff-context.sh b/t/t4055-diff-context.sh
> index 1384a8195705..c4b861c360cc 100755
> --- a/t/t4055-diff-context.sh
> +++ b/t/t4055-diff-context.sh
> @@ -52,6 +52,46 @@ test_expect_success 'diff.context honored by "log"' '
>   	test_grep "^ firstline" output
>   '

It's great that you have written tests for this patch but as I said
last time I think the new tests should be in t3701-add-interactive.sh
as we're interested in testing whether "git add -p" passes on
diff.context to "git diff" , not whether "git diff" respects
diff.context. I still think there are too many tests here as we know
that all the different "-p" commands share a single code path. Our
test suite is slow enough already so we do not want to add new tests
that do not increase our code coverage. I would suggest removing
these tests and instead add the following in t3701

test_expect_success 'add -p respects diff.context' '
	test_write_lines a b c d e f g h i j k l m >file &&
	git add file &&
	test_write_lines a b c d e f G h i j k l m >file &&
	echo y | git -c diff.context=5 add -p >actual &&
	test_grep "@@ -2,11 +2,11 @@" actual
'

test_expect_success 'add -p respects diff.interHunkContext' '
	test_write_lines a b c d e f g h i j k l m n o p q r s >file &&
	git add file &&
	test_write_lines a b c d E f g i i j k l m N o p q r s >file &&
	echo y | git -c diff.interhunkcontext=2 add -p >actual &&
	test_grep "@@ -2,16 +2,16 @@" actual
'

> +test_expect_success 'negative integer config parsing by "add"' '

Perhaps "add -p rejects negative diff.context" would be clearer?

> +	test_config diff.context -1 &&
> +	test_must_fail git add -p 2>output &&
> +	test_grep "diff.context cannot be negative" output
> +'

This is great but again we only need to test a single command and we
should do so in t3701. We should also check that negative values of
diff.interHunkContext are also rejected.

Best Wishes

Phillip

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On the Git mailing list, Junio C Hamano wrote (reply to this):

Phillip Wood <[email protected]> writes:

> Hi Leon
>
> On 10/05/2025 14:46, Leon Michalak via GitGitGadget wrote:
>> From: Leon Michalak <[email protected]>
>> Various builtins that use add-patch infrastructure do not respect
>> the user's diff.context and diff.interHunkContext file configurations.
>
> We could expand this slightly by adding
>
> This is because the plumbing commands used by "git add -p" to generate
> the diff do not read those config settings. Fix this by reading the
> config before generating the patch and passing it along to the diff
> command with the "-U" and "--inter-hunk-context" command-line options.
>
>> This patch fixes this inconsistency.
>> Signed-off-by: Leon Michalak <[email protected]>
>> ---
>
>> @@ -78,6 +82,19 @@ void init_add_i_state(struct add_i_state *s, struct repository *r)
>>   	repo_config_get_string(r, "diff.algorithm",
>>   			       &s->interactive_diff_algorithm);
>>   +	if (!repo_config_get_int(r, "diff.context", &context)) {
>> +		if (context < 0)
>> +			die(_("%s cannot be negative"), "diff.context");
>> +		else
>> +			s->context = context;
>> +	};
>> +	if (!repo_config_get_int(r, "diff.interHunkContext", &interhunkcontext)) {
>> +		if (interhunkcontext < 0)
>> +			die(_("%s cannot be negative"), "diff.interHunkContext");
>> +		else
>> +			s->interhunkcontext = interhunkcontext;
>> +	};
>
> Thanks for changing this. This iteration of the code changes looks good

Lose the ';' (semicolon) after closing {brace}s.
This is C; you do not need an empty statement after a {block}.

Everything in your review I am very happy to see.  Thanks for giving
a great review.

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On the Git mailing list, Phillip Wood wrote (reply to this):

On 13/05/2025 16:47, Junio C Hamano wrote:
> Phillip Wood <[email protected]> writes:
>> On 10/05/2025 14:46, Leon Michalak via GitGitGadget wrote:
>>
>>> @@ -78,6 +82,19 @@ void init_add_i_state(struct add_i_state *s, struct repository *r)
>>>    	repo_config_get_string(r, "diff.algorithm",
>>>    			       &s->interactive_diff_algorithm);
>>>    +	if (!repo_config_get_int(r, "diff.context", &context)) {
>>> +		if (context < 0)
>>> +			die(_("%s cannot be negative"), "diff.context");
>>> +		else
>>> +			s->context = context;
>>> +	};
>>> +	if (!repo_config_get_int(r, "diff.interHunkContext", &interhunkcontext)) {
>>> +		if (interhunkcontext < 0)
>>> +			die(_("%s cannot be negative"), "diff.interHunkContext");
>>> +		else
>>> +			s->interhunkcontext = interhunkcontext;
>>> +	};
>>
>> Thanks for changing this. This iteration of the code changes looks good
> > Lose the ';' (semicolon) after closing {brace}s.
> This is C; you do not need an empty statement after a {block}.

Oh well spotted, I'd missed that

Thanks

Phillip

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On the Git mailing list, Junio C Hamano wrote (reply to this):

Phillip Wood <[email protected]> writes:

> On 13/05/2025 16:47, Junio C Hamano wrote:
>> Phillip Wood <[email protected]> writes:
>>> On 10/05/2025 14:46, Leon Michalak via GitGitGadget wrote:
>>>
>>>> @@ -78,6 +82,19 @@ void init_add_i_state(struct add_i_state *s, struct repository *r)
>>>>    	repo_config_get_string(r, "diff.algorithm",
>>>>    			       &s->interactive_diff_algorithm);
>>>>    +	if (!repo_config_get_int(r, "diff.context", &context)) {
>>>> +		if (context < 0)
>>>> +			die(_("%s cannot be negative"), "diff.context");
>>>> +		else
>>>> +			s->context = context;
>>>> +	};
>>>> +	if (!repo_config_get_int(r, "diff.interHunkContext", &interhunkcontext)) {
>>>> +		if (interhunkcontext < 0)
>>>> +			die(_("%s cannot be negative"), "diff.interHunkContext");
>>>> +		else
>>>> +			s->interhunkcontext = interhunkcontext;
>>>> +	};
>>>
>>> Thanks for changing this. This iteration of the code changes looks good
>> Lose the ';' (semicolon) after closing {brace}s.
>> This is C; you do not need an empty statement after a {block}.
>
> Oh well spotted, I'd missed that

Heh, with enough number of eyeballs, all the bugs are shallow.

@@ -0,0 +1,10 @@
`-U<n>`::
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On the Git mailing list, Phillip Wood wrote (reply to this):

Hi Leon

On 10/05/2025 14:46, Leon Michalak via GitGitGadget wrote:
> From: Leon Michalak <[email protected]>
> > This patch compliments the previous commit, where builtins that use
> add-patch infrastructure now respect diff.context and
> diff.interHunkContext file configurations.
> > In particular, this patch helps users who don't want to set persistent
> context configurations or just want a way to override them on a one-time
> basis, by allowing the relevant builtins to accept corresponding command
> line options that override the file configurations.
> > This mimics commands such as diff and log, which allow for both context
> file configuration and command line overrides.

The code changes here mostly look good, I've left a few comments
below. I think the tests could be improved, I've left some suggestions
on limiting the number of tests while improving the coverage. The new
tests I'm suggesting that check invalid option combinations are the
basis for most of my code comments.

There is still the issue of what to do with -U0. As I mentioned
previously "git apply" will fail when we try to apply the patch. We
can either pass the appropriate flag when the context is zero or
possibly use -U0 to mean the default number of context lines.

> diff --git a/Documentation/diff-context-options.adoc b/Documentation/diff-context-options.adoc
> new file mode 100644
> index 000000000000..e161260358ff
> --- /dev/null
> +++ b/Documentation/diff-context-options.adoc
> @@ -0,0 +1,10 @@
> +`-U<n>`::
> +`--unified=<n>`::
> +	Generate diffs with _<n>_ lines of context. Defaults to `diff.context`
> +	or 3 if the config option is unset.
> +
> +`--inter-hunk-context=<n>`::
> +	Show the context between diff hunks, up to the specified _<number>_
> +	of lines, thereby fusing hunks that are close to each other.
> +	Defaults to `diff.interHunkContext` or 0 if the config option
> +	is unset.

Nice - we reuse the same text for all the "-p" commands.

> diff --git a/add-interactive.c b/add-interactive.c
> [...]
> @@ -98,6 +99,17 @@ void init_add_i_state(struct add_i_state *s, struct repository *r)
>   	repo_config_get_bool(r, "interactive.singlekey", &s->use_single_key);
>   	if (s->use_single_key)
>   		setbuf(stdin, NULL);
> +
> +	if (add_p_opt->context != -1) {
> +		if (add_p_opt->context < 0)
> +			die(_("%s cannot be negative"), "--unified");
> +		s->context = add_p_opt->context;
> +	}
> +	if (add_p_opt->interhunkcontext != -1) {
> +		if (add_p_opt->interhunkcontext < 0)
> +			die(_("%s cannot be negative"), "--inter-hunk-context");
> +		s->interhunkcontext = add_p_opt->interhunkcontext;
> +	}

Centralizing these checks like this is a good idea.

> @@ -1031,10 +1047,13 @@ static int run_diff(struct add_i_state *s, const struct pathspec *ps,
>   	if (count > 0) {
>   		struct child_process cmd = CHILD_PROCESS_INIT;
>   > -		strvec_pushl(&cmd.args, "git", "diff", "-p", "--cached",
> -			     oid_to_hex(!is_initial ? &oid :
> -					s->r->hash_algo->empty_tree),
> -			     "--", NULL);
> +		strvec_pushl(&cmd.args, "git", "diff", "-p", "--cached", NULL);
> +		if (s->context != -1)
> +			strvec_pushf(&cmd.args, "--unified=%i", s->context);
> +		if (s->interhunkcontext != -1)
> +			strvec_pushf(&cmd.args, "--inter-hunk-context=%i", s->interhunkcontext);
> +		strvec_pushl(&cmd.args, oid_to_hex(!is_initial ? &oid :
> +			     s->r->hash_algo->empty_tree), "--", NULL);

This is good - we propagate the values we were given on the
command-line.

> diff --git a/builtin/checkout.c b/builtin/checkout.c
> [...]
> @@ -564,8 +575,13 @@ static int checkout_paths(const struct checkout_opts *opts,
>   		else
>   			BUG("either flag must have been set, worktree=%d, index=%d",
>   			    opts->checkout_worktree, opts->checkout_index);
> -		return !!run_add_p(the_repository, patch_mode, rev,
> -				   &opts->pathspec);
> +		return !!run_add_p(the_repository, patch_mode, &add_p_opt,
> +				   rev, &opts->pathspec);
> +	} else {
> +		if (opts->patch_context != -1)
> +			die(_("the option '%s' requires '%s'"), "--unified", "--patch");
> +		if (opts->patch_interhunk_context != -1)
> +			die(_("the option '%s' requires '%s'"), "--inter-hunk-context", "--patch");
>   	}

This does not catch "git checkout -U 7" because this code is only run
if we're checking out paths. I think you need to check this is
checkout_main() instead.

> diff --git a/builtin/stash.c b/builtin/stash.c
> [...]
> @@ -1826,8 +1831,15 @@ static int push_stash(int argc, const char **argv, const char *prefix,
>   		die(_("the option '%s' requires '%s'"), "--pathspec-file-nul", "--pathspec-from-file");
>   	}
>   > +	if (!patch_mode) {
> +		if (add_p_opt.context != -1)
> +			die(_("the option '%s' requires '%s'"), "--unified", "--patch");
> +		if (add_p_opt.interhunkcontext != -1)
> +			die(_("the option '%s' requires '%s'"), "--inter-hunk-context", "--patch");
> +	}
> +

This needs to die on invalid context values as "git stash" seems to
ignore the exit code of the subprocess that checks for negative values.

> @@ -1877,8 +1892,17 @@ static int save_stash(int argc, const char **argv, const char *prefix,
>   		stash_msg = strbuf_join_argv(&stash_msg_buf, argc, argv, ' ');
>   >   	memset(&ps, 0, sizeof(ps));
> +
> +	if (!patch_mode) {
> +		if (add_p_opt.context != -1)
> +			die(_("the option '%s' requires '%s'"), "--unified", "--patch");
> +		if (add_p_opt.interhunkcontext != -1)
> +			die(_("the option '%s' requires '%s'"), "--inter-hunk-context", "--patch");

This needs to die on invalid context values as "git stash" seems to
ignore the exit code of the subprocess that checks for negative values.

> diff --git a/commit.h b/commit.h
> [...]
>   #include "object.h"
> +#include "add-interactive.h"
>   struct signature_check;
>   struct strbuf;

Lets not add this. Instead lets just add a declaration for "struct
add_p_opt" like the ones in the context line so that we don't end up
including everything from add-interactive.h when we only need a single
struct declaration.

> diff --git a/parse-options.h b/parse-options.h
> [...]
> +#define OPT_DIFF_UNIFIED(v) OPT_INTEGER_F('U', "unified", v,
>   N_("generate diffs with <n> lines context"), PARSE_OPT_NONEG)

This looks good

> +#define OPT_DIFF_INTERHUNK_CONTEXT(v) OPT_INTEGER_F(0, "inter-hunk-context", v, N_("show context between diff hunks up to the specified number of lines"), PARSE_OPT_NONEG)

This is a bit verbose but it  matches what is in diff.c.

> diff --git a/t/t4032-diff-inter-hunk-context.sh b/t/t4032-diff-inter-hunk-context.sh
> index bada0cbd32f7..d5aad6e143a7 100755
> --- a/t/t4032-diff-inter-hunk-context.sh
> +++ b/t/t4032-diff-inter-hunk-context.sh
> @@ -47,6 +47,31 @@ t() {
>   	"
>   }
>   > +t_patch() {
> +	use_config=
> +	git config --unset diff.interHunkContext
> +
> +	case $# in
> +	4) hunks=$4; cmd="add -p -U$3";;
> +	5) hunks=$5; cmd="add -p -U$3 --inter-hunk-context=$4";;
> +	6) hunks=$5; cmd="add -p -U$3"; git config diff.interHunkContext $4; use_config="(diff.interHunkContext=$4) ";;
> +	esac
> +	label="$use_config$cmd, $1 common $2"
> +	file=f$1
> +
> +	if ! test -f $file
> +	then
> +		f A $1 B >$file
> +		git add $file
> +		git commit -q -m. $file
> +		f X $1 Y >$file
> +	fi
> +
> +	test_expect_success "$label: count hunks ($hunks)" "
> +		test $(test_write_lines q | git $cmd $file | sed -n 's/^([0-9]*\/\([0-9]*\)) Stage this hunk.*/\1/p') = $hunks
> +	"
> +}
> +
>   cat <<EOF >expected.f1.0.1 || exit 1
>   diff --git a/f1 b/f1
>   --- a/f1
> @@ -107,6 +132,42 @@ t 3 lines	1	2	1	config
>   t 9 lines	3	2	2	config
>   t 9 lines	3	3	1	config
>   > +# common lines	ctx	intrctx	hunks
> +t_patch 1 line	0		2
> +t_patch 1 line	0	0	2
> +t_patch 1 line	0	1	1
> +t_patch 1 line	0	2	1
> +t_patch 1 line	1		1
> +
> +t_patch 2 lines	0		2
> +t_patch 2 lines	0	0	2
> +t_patch 2 lines	0	1	2
> +t_patch 2 lines	0	2	1
> +t_patch 2 lines	1		1
> +
> +t_patch 3 lines	1		2
> +t_patch 3 lines	1	0	2
> +t_patch 3 lines	1	1	1
> +t_patch 3 lines	1	2	1
> +
> +t_patch 9 lines	3		2
> +t_patch 9 lines	3	2	2
> +t_patch 9 lines	3	3	1
> +
> +#					use diff.interHunkContext?
> +t_patch 1 line	0	0	2	config
> +t_patch 1 line	0	1	1	config
> +t_patch 1 line	0	2	1	config
> +t_patch 9 lines	3	3	1	config
> +t_patch 2 lines	0	0	2	config
> +t_patch 2 lines	0	1	2	config
> +t_patch 2 lines	0	2	1	config
> +t_patch 3 lines	1	0	2	config
> +t_patch 3 lines	1	1	1	config
> +t_patch 3 lines	1	2	1	config
> +t_patch 9 lines	3	2	2	config
> +t_patch 9 lines	3	3	1	config
> +

There are 29 tests here and yet more below. I think we can
get the test coverage we need much more efficiently with the following
added to t3701

for cmd in add checkout restore 'commit -m file'
do
	test_expect_success "${cmd%% *} accepts -U and --inter-hunk-context" "
		test_write_lines a b c d e f g h i j k l m n o p q r s t u v >file &&
		git add file &&
		test_write_lines a b c d e F g h i j k l m n o p Q r s t u v >file &&
		echo y | git -c diff.context=5 -c diff.interhunkcontext=1 \
			$cmd -p -U 4 --inter-hunk-context 2 >actual &&
		test_grep \"@@ -2,20 +2,20 @@\" actual
	"
done
	
test_expect_success 'reset accepts -U and --inter-hunk-context' '
	test_write_lines a b c d e f g h i j k l m n o p q r s t u v >file &&
	git commit -m file file &&
	test_write_lines a b c d e F g h i j k l m n o p Q r s t u v >file &&
	git add file &&
	echo y | git -c diff.context=5 -c diff.interhunkcontext=1 \
		reset -p -U 4 --inter-hunk-context 2 >actual &&
	test_grep "@@ -2,20 +2,20 @@" actual
'

test_expect_success 'stash accepts -U and --inter-hunk-context' '
	test_write_lines a b c d e F g h i j k l m n o p Q r s t u v >file &&
	git commit -m file file &&
	test_write_lines a b c d e f g h i j k l m n o p q r s t u v >file &&
	echo y | git -c diff.context=5 -c diff.interhunkcontext=1 \
		stash -p -U 4 --inter-hunk-context 2 >actual &&
	test_grep "@@ -2,20 +2,20 @@" actual
'

Those tests will fail if any of the commands that accept "-p" do not
accept "-U" or "--inter-hunk-context" or if command-line arguments do
not override the config settings. We should also add tests in t3701 to
check that invalid option combinations and values are rejected like so

for cmd in add checkout commit reset restore 'stash save' 'stash push'
do
	test_expect_success "$cmd rejects invalid context options" "
		test_must_fail git $cmd -p -U -3 2>actual &&
		test_grep -e \"--unified cannot be negative\" actual &&

		test_must_fail git $cmd -p --inter-hunk-context -3 2>actual &&
		test_grep -e \"--inter-hunk-context cannot be negative\" actual &&

		test_must_fail git $cmd -U 7 2>actual &&
		test_grep -E \".--unified. requires .(--interactive/)?--patch.\" actual &&

		test_must_fail git $cmd --inter-hunk-context 2 2>actual &&
		test_grep -E \".--inter-hunk-context. requires .(--interactive/)?--patch.\" actual
	"
done

The "checkout", "stash save" and "stash push" tests above currently
fail because the implementation does not implement those checks
properly.

With a few tweaks this series will be looking very good

Best Wishes

Phillip

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On the Git mailing list, Phillip Wood wrote (reply to this):

On 13/05/2025 14:52, Phillip Wood wrote:
>> diff --git a/builtin/stash.c b/builtin/stash.c
>> [...]
>> @@ -1826,8 +1831,15 @@ static int push_stash(int argc, const char >> **argv, const char *prefix,
>>           die(_("the option '%s' requires '%s'"), "--pathspec-file- >> nul", "--pathspec-from-file");
>>       }
>> +    if (!patch_mode) {
>> +        if (add_p_opt.context != -1)
>> +            die(_("the option '%s' requires '%s'"), "--unified", "-- >> patch");
>> +        if (add_p_opt.interhunkcontext != -1)
>> +            die(_("the option '%s' requires '%s'"), "--inter-hunk- >> context", "--patch");
>> +    }
>> +
> > This needs to die on invalid context values as "git stash" seems to
> ignore the exit code of the subprocess that checks for negative values.

Looking more closely the problem is that it quits if there are no changes to stash before validating -U or --inter-hunk-context. I think it should validate the options before checking if there is anything to stash.

Best Wishes

Phillip

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On the Git mailing list, Leon Michalak wrote (reply to this):

Hey, thanks for the thorough review Philip. I will properly digest
this when I get some free time, but I just wanted to say (I probably
should have mentioned this so my bad) that the reason I didn't change
to test just the singular command (yet, anyway) is that someone else
thought this was a good idea testing all of them, so I wasn't sure
whether to touch it or not in the end, and thought I'd just submit
this v2 and gather more opinions. Was this perhaps the wrong approach
though?

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On the Git mailing list, [email protected] wrote (reply to this):

Hi Leon

On 13/05/2025 16:05, Leon Michalak wrote:
> Hey, thanks for the thorough review Philip. I will properly digest
> this when I get some free time, but I just wanted to say (I probably
> should have mentioned this so my bad) that the reason I didn't change
> to test just the singular command (yet, anyway) is that someone else
> thought this was a good idea testing all of them,

I'd missed that message - have you got a link to it please

> so I wasn't sure
> whether to touch it or not in the end, and thought I'd just submit
> this v2 and gather more opinions. Was this perhaps the wrong approach
> though?
If you get conflicting advise then it is a good idea to mention that in the cover letter and explain which option you went with and why.

Best Wishes

Phillip

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gitgitgadget bot commented May 13, 2025

This branch is now known as lm/add-p-context.

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gitgitgadget bot commented May 13, 2025

This patch series was integrated into seen via git@499dc4d.

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gitgitgadget bot commented May 14, 2025

This patch series was integrated into seen via git@cc0cba3.

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