From 86ffe9b7bc6034b16814fb3487395b78d96fd080 Mon Sep 17 00:00:00 2001
From: Derrick Stolee <stolee@gmail.com>
Date: Mon, 23 Sep 2024 14:15:24 -0400
Subject: [PATCH] sparse-checkout: disable advice in 'disable'

When running 'git sparse-checkout disable' with the sparse index
enabled, Git is expected to expand the index into a full index. However,
it currently outputs the advice message saying that that is unexpected
and likely due to an issue with the working directory.

Disable this advice message when in this code path. Establish a pattern
for doing a similar removal in the future.

Signed-off-by: Derrick Stolee <stolee@gmail.com>
---
 builtin/sparse-checkout.c                | 5 +++++
 sparse-index.c                           | 5 +++--
 sparse-index.h                           | 7 +++++++
 t/t1092-sparse-checkout-compatibility.sh | 5 ++++-
 4 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/builtin/sparse-checkout.c b/builtin/sparse-checkout.c
index 5ccf69686288d7..85b4fc06b350eb 100644
--- a/builtin/sparse-checkout.c
+++ b/builtin/sparse-checkout.c
@@ -924,6 +924,11 @@ static int sparse_checkout_disable(int argc, const char **argv,
 			     builtin_sparse_checkout_disable_options,
 			     builtin_sparse_checkout_disable_usage, 0);
 
+	/*
+	 * Disable the advice message for expanding a sparse index, as we
+	 * are expecting to do that when disabling sparse-checkout.
+	 */
+	give_advice_on_expansion = 0;
 	repo_read_index(the_repository);
 
 	memset(&pl, 0, sizeof(pl));
diff --git a/sparse-index.c b/sparse-index.c
index 9958656ded1931..0f9fb4df026f0f 100644
--- a/sparse-index.c
+++ b/sparse-index.c
@@ -19,9 +19,10 @@
  * advice for advice.sparseIndexExpanded when expanding a sparse index to a full
  * one. However, this is sometimes done on purpose, such as in the sparse-checkout
  * builtin, even when index.sparse=false. This may be disabled in
- * convert_to_sparse().
+ * convert_to_sparse() or by commands that know they will lead to a full
+ * expansion, but this message is not actionable.
  */
-static int give_advice_on_expansion = 1;
+int give_advice_on_expansion = 1;
 #define ADVICE_MSG \
 	"The sparse index is expanding to a full index, a slow operation.\n"   \
 	"Your working directory likely has contents that are outside of\n"     \
diff --git a/sparse-index.h b/sparse-index.h
index a16f3e67d75913..727034be7ca917 100644
--- a/sparse-index.h
+++ b/sparse-index.h
@@ -1,6 +1,13 @@
 #ifndef SPARSE_INDEX_H__
 #define SPARSE_INDEX_H__
 
+/*
+ * If performing an operation where the index is supposed to expand to a
+ * full index, then disable the advice message by setting this global to
+ * zero.
+ */
+extern int give_advice_on_expansion;
+
 struct index_state;
 #define SPARSE_INDEX_MEMORY_ONLY (1 << 0)
 int is_sparse_index_allowed(struct index_state *istate, int flags);
diff --git a/t/t1092-sparse-checkout-compatibility.sh b/t/t1092-sparse-checkout-compatibility.sh
index eb32da2a7f2ad6..6e230b54876061 100755
--- a/t/t1092-sparse-checkout-compatibility.sh
+++ b/t/t1092-sparse-checkout-compatibility.sh
@@ -2355,7 +2355,10 @@ test_expect_success 'advice.sparseIndexExpanded' '
 	mkdir -p sparse-index/deep/deeper2/deepest &&
 	touch sparse-index/deep/deeper2/deepest/bogus &&
 	git -C sparse-index status 2>err &&
-	grep "The sparse index is expanding to a full index" err
+	grep "The sparse index is expanding to a full index" err &&
+
+	git -C sparse-index sparse-checkout disable 2>err &&
+	test_line_count = 0 err
 '
 
 test_expect_success 'cat-file -p' '