From 58aaf59133b4167aefaab6083e80deb369894f79 Mon Sep 17 00:00:00 2001
From: Patrick Steinhardt <ps@pks.im>
Date: Fri, 29 Dec 2023 08:26:56 +0100
Subject: [PATCH] t: introduce GIT_TEST_DEFAULT_REF_FORMAT envvar

Introduce a new GIT_TEST_DEFAULT_REF_FORMAT environment variable that
lets developers run the test suite with a different default ref format
without impacting the ref format used by non-test Git invocations. This
is modeled after GIT_TEST_DEFAULT_OBJECT_FORMAT, which does the same
thing for the repository's object format.

Adapt the setup of the `REFFILES` test prerequisite to be conditionally
set based on the default ref format.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 t/README                |  3 +++
 t/test-lib-functions.sh |  5 +++++
 t/test-lib.sh           | 11 ++++++++++-
 3 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/t/README b/t/README
index 36463d0742..621d3b8c09 100644
--- a/t/README
+++ b/t/README
@@ -479,6 +479,9 @@ GIT_TEST_DEFAULT_HASH=<hash-algo> specifies which hash algorithm to
 use in the test scripts. Recognized values for <hash-algo> are "sha1"
 and "sha256".
 
+GIT_TEST_DEFAULT_REF_FORMAT=<format> specifies which ref storage format
+to use in the test scripts. Recognized values for <format> are "files".
+
 GIT_TEST_NO_WRITE_REV_INDEX=<boolean>, when true disables the
 'pack.writeReverseIndex' setting.
 
diff --git a/t/test-lib-functions.sh b/t/test-lib-functions.sh
index 03292602fb..61871b2a3b 100644
--- a/t/test-lib-functions.sh
+++ b/t/test-lib-functions.sh
@@ -1659,6 +1659,11 @@ test_detect_hash () {
 	test_hash_algo="${GIT_TEST_DEFAULT_HASH:-sha1}"
 }
 
+# Detect the hash algorithm in use.
+test_detect_ref_format () {
+	echo "${GIT_TEST_DEFAULT_REF_FORMAT:-files}"
+}
+
 # Load common hash metadata and common placeholder object IDs for use with
 # test_oid.
 test_oid_init () {
diff --git a/t/test-lib.sh b/t/test-lib.sh
index 4685cc3d48..fc93aa57e6 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -542,6 +542,8 @@ export EDITOR
 
 GIT_DEFAULT_HASH="${GIT_TEST_DEFAULT_HASH:-sha1}"
 export GIT_DEFAULT_HASH
+GIT_DEFAULT_REF_FORMAT="${GIT_TEST_DEFAULT_REF_FORMAT:-files}"
+export GIT_DEFAULT_REF_FORMAT
 GIT_TEST_MERGE_ALGORITHM="${GIT_TEST_MERGE_ALGORITHM:-ort}"
 export GIT_TEST_MERGE_ALGORITHM
 
@@ -1745,7 +1747,14 @@ parisc* | hppa*)
 	;;
 esac
 
-test_set_prereq REFFILES
+case "$GIT_DEFAULT_REF_FORMAT" in
+files)
+	test_set_prereq REFFILES;;
+*)
+	echo 2>&1 "error: unknown ref format $GIT_DEFAULT_REF_FORMAT"
+	exit 1
+	;;
+esac
 
 ( COLUMNS=1 && test $COLUMNS = 1 ) && test_set_prereq COLUMNS_CAN_BE_1
 test -z "$NO_CURL" && test_set_prereq LIBCURL
-- 
2.47.3