The object format for repositories can either be configured explicitly
by passing the `--object-format=` option to git-init(1) or git-clone(1),
or globally by setting the `GIT_DEFAULT_HASH` environment variable.
While the former makes sense, setting random environment variables is
not really a good user experience in case someone decides to only use
SHA256 repositories.
It is only natural to expect for a user that things like this can also
be configured via their config. As such, introduce a new config
"init.defaultObjectFormat", similar to "init.defaultBranch", that allows
the user to configure the default object format when creating new repos.
Signed-off-by: Patrick Steinhardt <ps@xxxxxx>
---
Documentation/config/init.txt | 5 ++++
setup.c | 40 ++++++++++++++++++++++++++++
t/t0001-init.sh | 50 +++++++++++++++++++++++++++++++++++
3 files changed, 95 insertions(+)
diff --git a/Documentation/config/init.txt b/Documentation/config/init.txt
index af03acdbcb..d6f8b6e61b 100644
--- a/Documentation/config/init.txt
+++ b/Documentation/config/init.txt
@@ -8,3 +8,8 @@ endif::[]
`init.defaultBranch`::
Allows overriding the default branch name e.g. when initializing
a new repository.
+`init.defaultObjectFormat`::
+ Allows overriding the default object format for new repositories. See
+ `--object-format=` in linkgit:git-init[1]. Both the command line option
+ and the `GIT_DEFAULT_HASH` environment variable take precedence over
+ this config.
diff --git a/setup.c b/setup.c
index 5dfcdc99dd..770ad1393f 100644
--- a/setup.c
+++ b/setup.c
@@ -2284,11 +2284,49 @@ static void separate_git_dir(const char *git_dir, const char *git_link)
write_file(git_link, "gitdir: %s", git_dir);
}
+struct default_format_config {
+ int hash;
+};
+
+static int read_default_format_config(const char *key, const char *value,
+ const struct config_context *ctx UNUSED,
+ void *payload)
+{
+ struct default_format_config *cfg = payload;
+ char *str = NULL;
+ int ret;
+
+ if (!strcmp(key, "init.defaultobjectformat")) {
+ ret = git_config_string(&str, key, value);
+ if (ret)
+ goto out;
+ cfg->hash = hash_algo_by_name(str);
+ if (cfg->hash == GIT_HASH_UNKNOWN)
+ warning(_("unknown hash algorithm '%s'"), str);
+ goto out;
+ }
+
+ ret = 0;
+out:
+ free(str);
+ return ret;
+}
+
static void repository_format_configure(struct repository_format *repo_fmt,
int hash, enum ref_storage_format ref_format)
{
+ struct default_format_config cfg = {
+ .hash = GIT_HASH_UNKNOWN,
+ };
+ struct config_options opts = {
+ .respect_includes = 1,
+ .ignore_repo = 1,
+ .ignore_worktree = 1,
+ };
const char *env;
+ config_with_options(read_default_format_config, &cfg, NULL, NULL, &opts);
+
/*
* If we already have an initialized repo, don't allow the user to
* specify a different algorithm, as that could cause corruption.
@@ -2304,6 +2342,8 @@ static void repository_format_configure(struct repository_format *repo_fmt,
if (env_algo == GIT_HASH_UNKNOWN)
die(_("unknown hash algorithm '%s'"), env);
repo_fmt->hash_algo = env_algo;
+ } else if (cfg.hash != GIT_HASH_UNKNOWN) {
+ repo_fmt->hash_algo = cfg.hash;
}
repo_set_hash_algo(the_repository, repo_fmt->hash_algo);
diff --git a/t/t0001-init.sh b/t/t0001-init.sh
index 795408e16c..cd34710f32 100755
--- a/t/t0001-init.sh
+++ b/t/t0001-init.sh
@@ -523,6 +523,56 @@ test_expect_success 'init honors --object-format' '
test_cmp expected actual
'
+test_expect_success 'init honors init.defaultObjectFormat' '
+ test_when_finished "rm -rf sha1 sha256" &&
+
+ test_config_global init.defaultObjectFormat sha1 &&
+ (
+ sane_unset GIT_DEFAULT_HASH &&
+ git init sha1 &&
+ git -C sha1 rev-parse --show-object-format >actual &&
+ echo sha1 >expected &&
+ test_cmp expected actual
+ ) &&
+
+ test_config_global init.defaultObjectFormat sha256 &&
+ (
+ sane_unset GIT_DEFAULT_HASH &&
+ git init sha256 &&
+ git -C sha256 rev-parse --show-object-format >actual &&
+ echo sha256 >expected &&
+ test_cmp expected actual
+ )
+'
+
+test_expect_success 'init warns about invalid init.defaultObjectFormat' '
+ test_when_finished "rm -rf repo" &&
+ test_config_global init.defaultObjectFormat garbage &&
+
+ echo "warning: unknown hash algorithm ${SQ}garbage${SQ}" >expect &&
+ git init repo 2>err &&
+ test_cmp expect err &&
+
+ git -C repo rev-parse --show-object-format >actual &&
+ echo $GIT_DEFAULT_HASH >expected &&
+ test_cmp expected actual
+'
+
+test_expect_success '--object-format overrides GIT_DEFAULT_HASH' '
+ test_when_finished "rm -rf repo" &&
+ GIT_DEFAULT_HASH=sha1 git init --object-format=sha256 repo &&
+ git -C repo rev-parse --show-object-format >actual &&
+ echo sha256 >expected
+'
+
+test_expect_success 'GIT_DEFAULT_HASH overrides init.defaultObjectFormat' '
+ test_when_finished "rm -rf repo" &&
+ test_config_global init.defaultObjectFormat sha1 &&
+ GIT_DEFAULT_HASH=sha256 git init repo &&
+ git -C repo rev-parse --show-object-format >actual &&
+ echo sha256 >expected
+'
+
test_expect_success 'extensions.objectFormat is not allowed with repo version 0' '
test_when_finished "rm -rf explicit-v0" &&
git init --object-format=sha256 explicit-v0 &&
--
2.46.0.46.g406f326d27.dirty
