Subject: [PATCH 1/3] add-patch: respect diff.context configuration

From: "Leon Michalak via GitGitGadget" <[email-masked]>
Date: Mon, 05 May 2025 09:18:37 +0000

From: Leon Michalak <[email-masked]>

This aims to teach relevant builtins (that take in `--patch`) to respect
the user's diff.context and diff.interHunkContext file configurations.

Since these are both UI options and `--patch` is designed for the end user,
I believe this was previously just an inconsistency, which this patch hopes
to address.

Signed-off-by: Leon Michalak <[email-masked]>
---
 add-interactive.c       | 16 ++++++++++----
 add-patch.c             |  6 ++++++
 t/t4055-diff-context.sh | 48 ++++++++++++++++++++++++++++++++++++++++-
 3 files changed, 65 insertions(+), 5 deletions(-)

diff --git a/add-interactive.c b/add-interactive.c
index 97ff35b6f12a..ad12dc416598 100644
--- a/add-interactive.c
+++ b/add-interactive.c
@@ -41,6 +41,8 @@ void init_add_i_state(struct add_i_state *s, struct repository *r)
 	const char *value;
 
 	s->r = r;
+	s->context = -1;
+	s->interhunkcontext = -1;
 
 	if (repo_config_get_value(r, "color.interactive", &value))
 		s->use_color = -1;
@@ -78,6 +80,9 @@ void init_add_i_state(struct add_i_state *s, struct repository *r)
 	repo_config_get_string(r, "diff.algorithm",
 			       &s->interactive_diff_algorithm);
 
+	repo_config_get_int(r, "diff.context", &s->context);
+	repo_config_get_int(r, "diff.interHunkContext", &s->interhunkcontext);
+
 	repo_config_get_bool(r, "interactive.singlekey", &s->use_single_key);
 	if (s->use_single_key)
 		setbuf(stdin, NULL);
@@ -1014,10 +1019,13 @@ 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);
 		for (i = 0; i < files->items.nr; i++)
 			if (files->selected[i])
 				strvec_push(&cmd.args,
diff --git a/add-patch.c b/add-patch.c
index 95c67d8c80c4..b43ca1600738 100644
--- a/add-patch.c
+++ b/add-patch.c
@@ -415,6 +415,8 @@ static int parse_diff(struct add_p_state *s, const struct pathspec *ps)
 {
 	struct strvec args = STRVEC_INIT;
 	const char *diff_algorithm = s->s.interactive_diff_algorithm;
+	int diff_context = s->s.context;
+	int diff_interhunkcontext = s->s.interhunkcontext;
 	struct strbuf *plain = &s->plain, *colored = NULL;
 	struct child_process cp = CHILD_PROCESS_INIT;
 	char *p, *pend, *colored_p = NULL, *colored_pend = NULL, marker = '\0';
@@ -424,6 +426,10 @@ static int parse_diff(struct add_p_state *s, const struct pathspec *ps)
 	int res;
 
 	strvec_pushv(&args, s->mode->diff_cmd);
+	if (diff_context != -1)
+		strvec_pushf(&args, "--unified=%i", diff_context);
+	if (diff_interhunkcontext != -1)
+		strvec_pushf(&args, "--inter-hunk-context=%i", diff_interhunkcontext);
 	if (diff_algorithm)
 		strvec_pushf(&args, "--diff-algorithm=%s", diff_algorithm);
 	if (s->revision) {
diff --git a/t/t4055-diff-context.sh b/t/t4055-diff-context.sh
index ec2804eea67c..9c024200ade7 100755
--- a/t/t4055-diff-context.sh
+++ b/t/t4055-diff-context.sh
@@ -49,7 +49,53 @@ test_expect_success 'diff.context honored by "log"' '
 	! grep firstline output &&
 	git config diff.context 8 &&
 	git log -1 -p >output &&
-	grep "^ firstline" output
+	grep "^ firstline" output &&
+	git config --unset diff.context
+'
+
+test_expect_success 'diff.context honored by "add"' '
+	git add -p >output &&
+	! grep firstline output &&
+	git config diff.context 8 &&
+	git add -p >output &&
+	grep "^ firstline" output &&
+	git config --unset diff.context
+'
+
+test_expect_success 'diff.context honored by "commit"' '
+	! git commit -p >output &&
+	! grep firstline output &&
+	git config diff.context 8 &&
+	! git commit -p >output &&
+	grep "^ firstline" output &&
+	git config --unset diff.context
+'
+
+test_expect_success 'diff.context honored by "checkout"' '
+	git checkout -p >output &&
+	! grep firstline output &&
+	git config diff.context 8 &&
+	git checkout -p >output &&
+	grep "^ firstline" output &&
+	git config --unset diff.context
+'
+
+test_expect_success 'diff.context honored by "stash"' '
+	! git stash -p >output &&
+	! grep firstline output &&
+	git config diff.context 8 &&
+	! git stash -p >output &&
+	grep "^ firstline" output &&
+	git config --unset diff.context
+'
+
+test_expect_success 'diff.context honored by "restore"' '
+	git restore -p >output &&
+	! grep firstline output &&
+	git config diff.context 8 &&
+	git restore -p >output &&
+	grep "^ firstline" output &&
+	git config --unset diff.context
 '
 
 test_expect_success 'The -U option overrides diff.context' '
-- 
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