scalar: teach 'clone' to support the --single-branch option

Just like `git clone`, the `scalar clone` command now also offers to
restrict the clone to a single branch.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/contrib/scalar/scalar.c b/contrib/scalar/scalar.c
index 60a9466421b0af99056d573ae2ea1b9cb6afba12..61b66e48aa8b793f88854e23dac268938a9b4785 100644 (file)
--- a/contrib/scalar/scalar.c
+++ b/contrib/scalar/scalar.c
@@ -327,12 +327,15 @@ static char *remote_default_branch(const char *url)
 static int cmd_clone(int argc, const char **argv)
 {
        const char *branch = NULL;
-       int full_clone = 0;
+       int full_clone = 0, single_branch = 0;
        struct option clone_options[] = {
                OPT_STRING('b', "branch", &branch, N_("<branch>"),
                           N_("branch to checkout after clone")),
                OPT_BOOL(0, "full-clone", &full_clone,
                         N_("when cloning, create full working directory")),
+               OPT_BOOL(0, "single-branch", &single_branch,
+                        N_("only download metadata for the branch that will "
+                           "be checked out")),
                OPT_END(),
        };
        const char * const clone_usage[] = {
@@ -403,7 +406,9 @@ static int cmd_clone(int argc, const char **argv)
 
        if (set_config("remote.origin.url=%s", url) ||
            set_config("remote.origin.fetch="
-                      "+refs/heads/*:refs/remotes/origin/*") ||
+                      "+refs/heads/%s:refs/remotes/origin/%s",
+                      single_branch ? branch : "*",
+                      single_branch ? branch : "*") ||
            set_config("remote.origin.promisor=true") ||
            set_config("remote.origin.partialCloneFilter=blob:none")) {
                res = error(_("could not configure remote in '%s'"), dir);

diff --git a/contrib/scalar/scalar.txt b/contrib/scalar/scalar.txt
index e8730967f1681778bff1f999f5462e24079537d8..56f744a4aa95864258ba53d8f61c8162523b712e 100644 (file)
--- a/contrib/scalar/scalar.txt
+++ b/contrib/scalar/scalar.txt
@@ -8,7 +8,7 @@ scalar - an opinionated repository management tool
 SYNOPSIS
 --------
 [verse]
-scalar clone [--branch <main-branch>] [--full-clone] <url> [<enlistment>]
+scalar clone [--single-branch] [--branch <main-branch>] [--full-clone] <url> [<enlistment>]
 scalar list
 scalar register [<enlistment>]
 scalar unregister [<enlistment>]
@@ -57,6 +57,16 @@ HEAD[:<directory>]`.
        Instead of checking out the branch pointed to by the cloned
        repository's HEAD, check out the `<name>` branch instead.
 
+--[no-]single-branch::
+       Clone only the history leading to the tip of a single branch, either
+       specified by the `--branch` option or the primary branch remote's
+       `HEAD` points at.
++
+Further fetches into the resulting repository will only update the
+remote-tracking branch for the branch this option was used for the initial
+cloning. If the HEAD at the remote did not point at any branch when
+`--single-branch` clone was made, no remote-tracking branch is created.
+
 --[no-]full-clone::
        A sparse-checkout is initialized by default. This behavior can be
        turned off via `--full-clone`.

diff --git a/contrib/scalar/t/t9099-scalar.sh b/contrib/scalar/t/t9099-scalar.sh
index 984d69e8f75cf959a2972473f99e27a67e265b57..f60e086d6f9906055c13577d9dcbbbf267124171 100755 (executable)
--- a/contrib/scalar/t/t9099-scalar.sh
+++ b/contrib/scalar/t/t9099-scalar.sh
@@ -45,13 +45,17 @@ test_expect_success 'set up repository to clone' '
 
 test_expect_success 'scalar clone' '
        second=$(git rev-parse --verify second:second.t) &&
-       scalar clone "file://$(pwd)" cloned &&
+       scalar clone "file://$(pwd)" cloned --single-branch &&
        (
                cd cloned/src &&
 
                git config --get --global --fixed-value maintenance.repo \
                        "$(pwd)" &&
 
+               git for-each-ref --format="%(refname)" refs/remotes/origin/ >actual &&
+               echo "refs/remotes/origin/parallel" >expect &&
+               test_cmp expect actual &&
+
                test_path_is_missing 1/2 &&
                test_must_fail git rev-list --missing=print $second &&
                git rev-list $second &&