Merge branch 'bc/use-sha256-by-default-in-3.0' into ps/config-wo-the-repository

* bc/use-sha256-by-default-in-3.0:
  Enable SHA-256 by default in breaking changes mode
  help: add a build option for default hash
  t5300: choose the built-in hash outside of a repo
  t4042: choose the built-in hash outside of a repo
  t1007: choose the built-in hash outside of a repo
  t: default to compile-time default hash if not set
  setup: use the default algorithm to initialize repo format
  Use legacy hash for legacy formats
  builtin: use default hash when outside a repository
  hash: add a constant for the legacy hash algorithm
  hash: add a constant for the default hash algorithm

5 files changed, 25 insertions, 9 deletions

diff --git a/t/t1007-hash-object.sh b/t/t1007-hash-object.sh
index 64658b3ba5..de076293b6 100755
--- a/t/t1007-hash-object.sh
+++ b/t/t1007-hash-object.sh
@@ -252,9 +252,9 @@ test_expect_success '--literally complains about non-standard types' '
 	test_must_fail git hash-object -t bogus --literally --stdin
 '
 
-test_expect_success '--stdin outside of repository (uses SHA-1)' '
+test_expect_success '--stdin outside of repository (uses default hash)' '
 	nongit git hash-object --stdin <hello >actual &&
-	echo "$(test_oid --hash=sha1 hello)" >expect &&
+	echo "$(test_oid --hash=builtin hello)" >expect &&
 	test_cmp expect actual
 '
 
diff --git a/t/t4042-diff-textconv-caching.sh b/t/t4042-diff-textconv-caching.sh
index ff0e73531b..31018ceba2 100755
--- a/t/t4042-diff-textconv-caching.sh
+++ b/t/t4042-diff-textconv-caching.sh
@@ -120,6 +120,14 @@ test_expect_success 'log notes cache and still use cache for -p' '
 '
 
 test_expect_success 'caching is silently ignored outside repo' '
+	test_oid_cache <<-\EOM &&
+	oid1 sha1:5626abf
+	oid1 sha256:a4ed1f3
+	oid2 sha1:f719efd
+	oid2 sha256:aa9e7dc
+	EOM
+	oid1=$(test_oid --hash=builtin oid1) &&
+	oid2=$(test_oid --hash=builtin oid2) &&
 	mkdir -p non-repo &&
 	echo one >non-repo/one &&
 	echo two >non-repo/two &&
@@ -129,9 +137,9 @@ test_expect_success 'caching is silently ignored outside repo' '
 		   -c diff.test.textconv="tr a-z A-Z <" \
 		   -c diff.test.cachetextconv=true \
 		   diff --no-index one two >actual &&
-	cat >expect <<-\EOF &&
+	cat >expect <<-EOF &&
 	diff --git a/one b/two
-	index 5626abf..f719efd 100644
+	index $oid1..$oid2 100644
 	--- a/one
 	+++ b/two
 	@@ -1 +1 @@
diff --git a/t/t5300-pack-object.sh b/t/t5300-pack-object.sh
index ae72158b94..73445782e7 100755
--- a/t/t5300-pack-object.sh
+++ b/t/t5300-pack-object.sh
@@ -525,7 +525,7 @@ test_expect_success 'index-pack --strict <pack> works in non-repo' '
 	test_path_is_file foo.idx
 '
 
-test_expect_success SHA1 'show-index works OK outside a repository' '
+test_expect_success DEFAULT_HASH_ALGORITHM 'show-index works OK outside a repository' '
 	nongit git show-index <foo.idx
 '
 
@@ -658,7 +658,7 @@ do
 		test_commit -C repo initial &&
 		git -C repo repack -ad &&
 		git -C repo verify-pack "$(pwd)"/repo/.git/objects/pack/*.idx &&
-		if test $hash = sha1
+		if test $hash = $GIT_TEST_BUILTIN_HASH
 		then
 			nongit git verify-pack "$(pwd)"/repo/.git/objects/pack/*.idx
 		else
@@ -676,7 +676,7 @@ do
 		test_commit -C repo initial &&
 		git -C repo repack -ad &&
 		git -C repo index-pack --verify "$(pwd)"/repo/.git/objects/pack/*.pack &&
-		if test $hash = sha1
+		if test $hash = $GIT_TEST_BUILTIN_HASH
 		then
 			nongit git index-pack --verify "$(pwd)"/repo/.git/objects/pack/*.pack
 		else
diff --git a/t/test-lib-functions.sh b/t/test-lib-functions.sh
index 6230746cc4..a28de7b19b 100644
--- a/t/test-lib-functions.sh
+++ b/t/test-lib-functions.sh
@@ -1707,7 +1707,7 @@ test_set_hash () {
 
 # Detect the hash algorithm in use.
 test_detect_hash () {
-	case "$GIT_TEST_DEFAULT_HASH" in
+	case "${GIT_TEST_DEFAULT_HASH:-$GIT_TEST_BUILTIN_HASH}" in
 	"sha256")
 	    test_hash_algo=sha256
 	    test_compat_hash_algo=sha1
@@ -1779,6 +1779,9 @@ test_oid () {
 	--hash=compat)
 		algo="$test_compat_hash_algo" &&
 		shift;;
+	--hash=builtin)
+		algo="$GIT_TEST_BUILTIN_HASH" &&
+		shift;;
 	--hash=*)
 		algo="${1#--hash=}" &&
 		shift;;
diff --git a/t/test-lib.sh b/t/test-lib.sh
index 51370a201c..6dc2022ee1 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -536,7 +536,8 @@ export GIT_COMMITTER_EMAIL GIT_COMMITTER_NAME
 export GIT_COMMITTER_DATE GIT_AUTHOR_DATE
 export EDITOR
 
-GIT_DEFAULT_HASH="${GIT_TEST_DEFAULT_HASH:-sha1}"
+GIT_TEST_BUILTIN_HASH=$("$GIT_BUILD_DIR/git" version --build-options | sed -ne 's/^default-hash: //p')
+GIT_DEFAULT_HASH="${GIT_TEST_DEFAULT_HASH:-$GIT_TEST_BUILTIN_HASH}"
 export GIT_DEFAULT_HASH
 GIT_DEFAULT_REF_FORMAT="${GIT_TEST_DEFAULT_REF_FORMAT:-files}"
 export GIT_DEFAULT_REF_FORMAT
@@ -1908,6 +1909,10 @@ test_lazy_prereq SHA1 '
 	esac
 '
 
+test_lazy_prereq DEFAULT_HASH_ALGORITHM '
+	test "$GIT_TEST_BUILTIN_HASH" = "$GIT_DEFAULT_HASH"
+'
+
 test_lazy_prereq DEFAULT_REPO_FORMAT '
 	test_have_prereq SHA1,REFFILES
 '