builtin/clone: teach git-clone(1) the --revision= option

index 8d0476f6dc..1069d56e71 100644 --- a/Documentation/git-clone.txt +++ b/Documentation/git-clone.txt @@ -221,6 +221,15 @@ objects from the source repository into a pack in the cloned repository. `--branch` can also take tags and detaches the `HEAD` at that commit in the resulting repository. +`--revision=<rev>`:: + Create a new repository, and fetch the history leading to the given + revision _<rev>_ (and nothing else), without making any remote-tracking + branch, and without making any local branch, and detach `HEAD` to + _<rev>_. The argument can be a ref name (e.g. `refs/heads/main` or + `refs/tags/v1.0`) that peels down to a commit, or a hexadecimal object + name. + This option is incompatible with `--branch` and `--mirror`. + `-u` _<upload-pack>_:: `--upload-pack` _<upload-pack>_:: When given, and the repository to clone from is accessed

index 1d421c8f75..f9a2ecbe9c 100644 --- a/builtin/clone.c +++ b/builtin/clone.c @@ -59,6 +59,7 @@ struct clone_opts { int wants_head; + int detach; }; #define CLONE_OPTS_INIT { \ .wants_head = 1 /* default enabled */ \ @@ -565,11 +566,11 @@ static void update_remote_refs(const struct ref *refs, } } -static void update_head(const struct ref *our, const struct ref *remote, +static void update_head(struct clone_opts *opts, const struct ref *our, const struct ref *remote, const char *unborn, const char *msg) { const char *head; - if (our && skip_prefix(our->name, "refs/heads/", &head)) { + if (our && !opts->detach && skip_prefix(our->name, "refs/heads/", &head)) { /* Local default branch link */ if (refs_update_symref(get_main_ref_store(the_repository), "HEAD", our->name, NULL) < 0) die(_("unable to update HEAD")); @@ -580,8 +581,9 @@ static void update_head(const struct ref *our, const struct ref *remote, install_branch_config(0, head, remote_name, our->name); } } else if (our) { - struct commit *c = lookup_commit_reference(the_repository, - &our->old_oid); + struct commit *c = lookup_commit_or_die(&our->old_oid, + our->name); + /* --branch specifies a non-branch (i.e. tags), detach HEAD */ refs_update_ref(get_main_ref_store(the_repository), msg, "HEAD", &c->object.oid, NULL, REF_NO_DEREF, @@ -900,6 +902,7 @@ int cmd_clone(int argc, int option_filter_submodules = -1; /* unspecified */ struct string_list server_options = STRING_LIST_INIT_NODUP; const char *bundle_uri = NULL; + char *option_rev = NULL; struct clone_opts opts = CLONE_OPTS_INIT; @@ -943,6 +946,8 @@ int cmd_clone(int argc, N_("use <name> instead of 'origin' to track upstream")), OPT_STRING('b', "branch", &option_branch, N_("branch"), N_("checkout <branch> instead of the remote's HEAD")), + OPT_STRING(0, "revision", &option_rev, N_("rev"), + N_("clone single revision <rev> and check out")), OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"), N_("path to git-upload-pack on the remote")), OPT_STRING(0, "depth", &option_depth, N_("depth"), @@ -1279,7 +1284,7 @@ int cmd_clone(int argc, strbuf_addstr(&branch_top, src_ref_prefix); git_config_set("core.bare", "true"); - } else { + } else if (!option_rev) { strbuf_addf(&branch_top, "refs/remotes/%s/", remote_name); } @@ -1298,8 +1303,9 @@ int cmd_clone(int argc, remote = remote_get_early(remote_name); - refspec_appendf(&remote->fetch, "+%s*:%s*", src_ref_prefix, - branch_top.buf); + if (!option_rev) + refspec_appendf(&remote->fetch, "+%s*:%s*", src_ref_prefix, + branch_top.buf); path = get_repo_path(remote->url.v[0], &is_bundle); is_local = option_local != 0 && path && !is_bundle; @@ -1342,6 +1348,11 @@ int cmd_clone(int argc, transport_set_option(transport, TRANS_OPT_KEEP, "yes"); + die_for_incompatible_opt2(!!option_rev, "--revision", + !!option_branch, "--branch"); + die_for_incompatible_opt2(!!option_rev, "--revision", + option_mirror, "--mirror"); + if (reject_shallow) transport_set_option(transport, TRANS_OPT_REJECT_SHALLOW, "1"); if (option_depth) @@ -1378,7 +1389,14 @@ int cmd_clone(int argc, if (transport->smart_options && !deepen && !filter_options.choice) transport->smart_options->check_self_contained_and_connected = 1; - strvec_push(&transport_ls_refs_options.ref_prefixes, "HEAD"); + if (option_rev) { + option_tags = 0; + option_single_branch = 0; + opts.wants_head = 0; + opts.detach = 1; + + refspec_append(&remote->fetch, option_rev); + } if (option_tags || option_branch) /* @@ -1393,6 +1411,17 @@ int cmd_clone(int argc, expand_ref_prefix(&transport_ls_refs_options.ref_prefixes, option_branch); + /* + * As part of transport_get_remote_refs() the server tells us the hash + * algorithm, which we require to initialize the repo. But calling that + * function without any ref prefix, will cause the server to announce + * all known refs. If the argument passed to --revision was a hex oid, + * ref_prefixes will be empty so we fall back to asking about HEAD to + * reduce traffic from the server. + */ + if (opts.wants_head || transport_ls_refs_options.ref_prefixes.nr == 0) + strvec_push(&transport_ls_refs_options.ref_prefixes, "HEAD"); + refs = transport_get_remote_refs(transport, &transport_ls_refs_options); /* @@ -1501,6 +1530,11 @@ int cmd_clone(int argc, if (!our_head_points_at) die(_("Remote branch %s not found in upstream %s"), option_branch, remote_name); + } else if (option_rev) { + our_head_points_at = mapped_refs; + if (!our_head_points_at) + die(_("Remote revision %s not found in upstream %s"), + option_rev, remote_name); } else if (remote_head_points_at) { our_head_points_at = remote_head_points_at; } else if (remote_head) { @@ -1539,8 +1573,9 @@ int cmd_clone(int argc, free(to_free); } - write_refspec_config(src_ref_prefix, our_head_points_at, - remote_head_points_at, &branch_top); + if (!option_rev) + write_refspec_config(src_ref_prefix, our_head_points_at, + remote_head_points_at, &branch_top); if (filter_options.choice) partial_clone_register(remote_name, &filter_options); @@ -1556,7 +1591,7 @@ int cmd_clone(int argc, branch_top.buf, reflog_msg.buf, transport, !is_local); - update_head(our_head_points_at, remote_head, unborn_head, reflog_msg.buf); + update_head(&opts, our_head_points_at, remote_head, unborn_head, reflog_msg.buf); /* * We want to show progress for recursive submodule clones iff

index 35f25ca4a1..b5f917926b 100644 --- a/t/meson.build +++ b/t/meson.build @@ -721,6 +721,7 @@ integration_tests = [ 't5617-clone-submodules-remote.sh', 't5618-alternate-refs.sh', 't5619-clone-local-ambiguous-transport.sh', + 't5621-clone-revision.sh', 't5700-protocol-v1.sh', 't5701-git-serve.sh', 't5702-protocol-v2.sh',

new file mode 100755 index 0000000000..db3b8cff55 --- /dev/null +++ b/t/t5621-clone-revision.sh @@ -0,0 +1,122 @@ +#!/bin/sh + +test_description='tests for git clone --revision' +GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main +export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME + +. ./test-lib.sh + +test_expect_success 'setup' ' + test_commit --no-tag "initial commit" README "Hello" && + test_commit --annotate "second commit" README "Hello world" v1.0 && + test_commit --no-tag "third commit" README "Hello world!" && + git switch -c feature v1.0 && + test_commit --no-tag "feature commit" README "Hello world!" && + git switch main +' + +test_expect_success 'clone with --revision being a branch' ' + test_when_finished "rm -rf dst" && + git clone --revision=refs/heads/feature . dst && + git rev-parse refs/heads/feature >expect && + git -C dst rev-parse HEAD >actual && + test_must_fail git -C dst symbolic-ref -q HEAD >/dev/null && + test_cmp expect actual && + git -C dst for-each-ref refs >expect && + test_must_be_empty expect && + test_must_fail git -C dst config remote.origin.fetch +' + +test_expect_success 'clone with --depth and --revision being a branch' ' + test_when_finished "rm -rf dst" && + git clone --no-local --depth=1 --revision=refs/heads/feature . dst && + git rev-parse refs/heads/feature >expect && + git -C dst rev-parse HEAD >actual && + test_must_fail git -C dst symbolic-ref -q HEAD >/dev/null && + test_cmp expect actual && + git -C dst for-each-ref refs >expect && + test_must_be_empty expect && + test_must_fail git -C dst config remote.origin.fetch && + git -C dst rev-list HEAD >actual && + test_line_count = 1 actual +' + +test_expect_success 'clone with --revision being a tag' ' + test_when_finished "rm -rf dst" && + git clone --revision=refs/tags/v1.0 . dst && + git rev-parse refs/tags/v1.0^{} >expect && + git -C dst rev-parse HEAD >actual && + test_must_fail git -C dst symbolic-ref -q HEAD >/dev/null && + test_cmp expect actual && + git -C dst for-each-ref refs >expect && + test_must_be_empty expect && + test_must_fail git -C dst config remote.origin.fetch +' + +test_expect_success 'clone with --revision being HEAD' ' + test_when_finished "rm -rf dst" && + git clone --revision=HEAD . dst && + git rev-parse HEAD >expect && + git -C dst rev-parse HEAD >actual && + test_must_fail git -C dst symbolic-ref -q HEAD >/dev/null && + test_cmp expect actual && + git -C dst for-each-ref refs >expect && + test_must_be_empty expect && + test_must_fail git -C dst config remote.origin.fetch +' + +test_expect_success 'clone with --revision being a raw commit hash' ' + test_when_finished "rm -rf dst" && + oid=$(git rev-parse refs/heads/feature) && + git clone --revision=$oid . dst && + echo $oid >expect && + git -C dst rev-parse HEAD >actual && + test_must_fail git -C dst symbolic-ref -q HEAD >/dev/null && + test_cmp expect actual && + git -C dst for-each-ref refs >expect && + test_must_be_empty expect && + test_must_fail git -C dst config remote.origin.fetch +' + +test_expect_success 'clone with --revision and --bare' ' + test_when_finished "rm -rf dst" && + git clone --revision=refs/heads/main --bare . dst && + oid=$(git rev-parse refs/heads/main) && + git -C dst cat-file -t $oid >actual && + echo "commit" >expect && + test_cmp expect actual && + git -C dst for-each-ref refs >expect && + test_must_be_empty expect && + test_must_fail git -C dst config remote.origin.fetch +' + +test_expect_success 'clone with --revision being a short raw commit hash' ' + test_when_finished "rm -rf dst" && + oid=$(git rev-parse --short refs/heads/feature) && + test_must_fail git clone --revision=$oid . dst 2>err && + test_grep "fatal: Remote revision $oid not found in upstream origin" err +' + +test_expect_success 'clone with --revision being a tree hash' ' + test_when_finished "rm -rf dst" && + oid=$(git rev-parse refs/heads/feature^{tree}) && + test_must_fail git clone --revision=$oid . dst 2>err && + test_grep "error: object $oid is a tree, not a commit" err +' + +test_expect_success 'clone with --revision being the parent of a ref fails' ' + test_when_finished "rm -rf dst" && + test_must_fail git clone --revision=refs/heads/main^ . dst +' + +test_expect_success 'clone with --revision and --branch fails' ' + test_when_finished "rm -rf dst" && + test_must_fail git clone --revision=refs/heads/main --branch=main . dst +' + +test_expect_success 'clone with --revision and --mirror fails' ' + test_when_finished "rm -rf dst" && + test_must_fail git clone --revision=refs/heads/main --mirror . dst +' + +test_done