Merge branch 'jk/symbolic-ref-no-symlinks' into HEAD

* jk/symbolic-ref-no-symlinks:
  create_symref: drop support for writing symbolic links
  create_symref: deprecate support for writing symbolic links

Author: peff

Makefile

@@ -81,9 +81,6 @@ include shared.mak
 #
 # Define NO_SYS_SELECT_H if you don't have sys/select.h.
 #
-# Define NO_SYMLINK_HEAD if you never want .git/HEAD to be a symbolic link.
-# Enable it on Windows.  By default, symrefs are still used.
-#
 # Define NO_SVN_TESTS if you want to skip time-consuming SVN interoperability
 # tests.  These tests take up a significant amount of the total test time
 # but are not needed unless you plan to talk to SVN repos.
@@ -1815,9 +1812,6 @@ ifdef OPEN_RETURNS_EINTR
 	COMPAT_CFLAGS += -DOPEN_RETURNS_EINTR
 	COMPAT_OBJS += compat/open.o
 endif
-ifdef NO_SYMLINK_HEAD
-	BASIC_CFLAGS += -DNO_SYMLINK_HEAD
-endif
 ifdef NO_GETTEXT
 	BASIC_CFLAGS += -DNO_GETTEXT
 	USE_GETTEXT_SCHEME ?= fallthrough

config.mak.uname

@@ -238,7 +238,6 @@ ifeq ($(uname_O),Cygwin)
 		NO_D_TYPE_IN_DIRENT = YesPlease
 		NO_STRCASESTR = YesPlease
 		NO_MEMMEM = YesPlease
-		NO_SYMLINK_HEAD = YesPlease
 		NO_IPV6 = YesPlease
 		OLD_ICONV = UnfortunatelyYes
 		# There are conflicting reports about this.
@@ -446,7 +445,6 @@ ifeq ($(uname_S),Windows)
 	NEEDS_CRYPTO_WITH_SSL = YesPlease
 	NO_LIBGEN_H = YesPlease
 	NO_POLL = YesPlease
-	NO_SYMLINK_HEAD = YesPlease
 	NO_IPV6 = YesPlease
 	NO_SETENV = YesPlease
 	NO_STRCASESTR = YesPlease
@@ -661,7 +659,6 @@ ifeq ($(uname_S),MINGW)
 	NEEDS_CRYPTO_WITH_SSL = YesPlease
 	NO_LIBGEN_H = YesPlease
 	NO_POLL = YesPlease
-	NO_SYMLINK_HEAD = YesPlease
 	NO_SETENV = YesPlease
 	NO_STRCASESTR = YesPlease
 	NO_STRLCPY = YesPlease

configure.ac

@@ -1195,9 +1195,6 @@ AC_COMPILE_IFELSE([BSD_SYSCTL_SRC],
 GIT_CONF_SUBST([HAVE_BSD_SYSCTL])
 
 ## Other checks.
-# Define NO_SYMLINK_HEAD if you never want .git/HEAD to be a symbolic link.
-# Enable it on Windows.  By default, symrefs are still used.
-#
 # Define NO_PTHREADS if we do not have pthreads.
 #
 # Define PTHREAD_LIBS to the linker flag used for Pthread support.

refs/files-backend.c

@@ -2044,24 +2044,6 @@ static int commit_ref_update(struct files_ref_store *refs,
 	return 0;
 }
 
-#ifdef NO_SYMLINK_HEAD
-#define create_ref_symlink(a, b) (-1)
-#else
-static int create_ref_symlink(struct ref_lock *lock, const char *target)
-{
-	int ret = -1;
-
-	char *ref_path = get_locked_file_path(&lock->lk);
-	unlink(ref_path);
-	ret = symlink(target, ref_path);
-	free(ref_path);
-
-	if (ret)
-		fprintf(stderr, "no symlink - falling back to symbolic ref\n");
-	return ret;
-}
-#endif
-
 static int create_symref_lock(struct ref_lock *lock, const char *target,
 			      struct strbuf *err)
 {
@@ -3178,14 +3160,6 @@ static int files_transaction_finish(struct ref_store *ref_store,
 			}
 		}
 
-		/*
-		 * We try creating a symlink, if that succeeds we continue to the
-		 * next update. If not, we try and create a regular symref.
-		 */
-		if (update->new_target && refs->prefer_symlink_refs)
-			if (!create_ref_symlink(lock, update->new_target))
-				continue;
-
 		if (update->flags & REF_NEEDS_COMMIT) {
 			clear_loose_ref_cache(refs);
 			if (commit_ref(lock)) {

t/t0600-reffiles-backend.sh

@@ -467,21 +467,6 @@ test_expect_success POSIXPERM 'git reflog expire honors core.sharedRepository' '
 	esac
 '
 
-test_expect_success SYMLINKS 'symref transaction supports symlinks' '
-	test_when_finished "git symbolic-ref -d TEST_SYMREF_HEAD" &&
-	git update-ref refs/heads/new @ &&
-	test_config core.prefersymlinkrefs true &&
-	cat >stdin <<-EOF &&
-	start
-	symref-create TEST_SYMREF_HEAD refs/heads/new
-	prepare
-	commit
-	EOF
-	git update-ref --no-deref --stdin <stdin &&
-	test_path_is_symlink .git/TEST_SYMREF_HEAD &&
-	test "$(test_readlink .git/TEST_SYMREF_HEAD)" = refs/heads/new
-'
-
 test_expect_success 'symref transaction supports false symlink config' '
 	test_when_finished "git symbolic-ref -d TEST_SYMREF_HEAD" &&
 	git update-ref refs/heads/new @ &&

t/t7201-co.sh

@@ -406,18 +406,6 @@ test_expect_success 'checkout w/--track from tag fails' '
 	test "z$(git rev-parse main^0)" = "z$(git rev-parse HEAD)"
 '
 
-test_expect_success 'detach a symbolic link HEAD' '
-	git checkout main &&
-	git config --bool core.prefersymlinkrefs yes &&
-	git checkout side &&
-	git checkout main &&
-	it=$(git symbolic-ref HEAD) &&
-	test "z$it" = zrefs/heads/main &&
-	here=$(git rev-parse --verify refs/heads/main) &&
-	git checkout side^ &&
-	test "z$(git rev-parse --verify refs/heads/main)" = "z$here"
-'
-
 test_expect_success 'checkout with --track fakes a sensible -b <name>' '
 	git config remote.origin.fetch "+refs/heads/*:refs/remotes/origin/*" &&
 	git update-ref refs/remotes/origin/koala/bear renamer &&

t/t9903-bash-prompt.sh

@@ -49,15 +49,6 @@ test_expect_success 'prompt - branch name' '
 	test_cmp expected "$actual"
 '
 
-test_expect_success SYMLINKS 'prompt - branch name - symlink symref' '
-	printf " (main)" >expected &&
-	test_when_finished "git checkout main" &&
-	test_config core.preferSymlinkRefs true &&
-	git checkout main &&
-	__git_ps1 >"$actual" &&
-	test_cmp expected "$actual"
-'
-
 test_expect_success 'prompt - unborn branch' '
 	printf " (unborn)" >expected &&
 	git checkout --orphan unborn &&