diff --git a/Documentation/git-show-ref.txt b/Documentation/git-show-ref.txt index 9afcd4d536..ba75747005 100644 --- a/Documentation/git-show-ref.txt +++ b/Documentation/git-show-ref.txt @@ -15,6 +15,7 @@ SYNOPSIS [-s | --hash[=]] [--abbrev[=]] [--] [...] 'git show-ref' --exclude-existing[=] +'git show-ref' --exists DESCRIPTION ----------- @@ -30,6 +31,10 @@ The `--exclude-existing` form is a filter that does the inverse. It reads refs from stdin, one ref per line, and shows those that don't exist in the local repository. +The `--exists` form can be used to check for the existence of a single +references. This form does not verify whether the reference resolves to an +actual object. + Use of this utility is encouraged in favor of directly accessing files under the `.git` directory. @@ -65,6 +70,12 @@ OPTIONS Aside from returning an error code of 1, it will also print an error message if `--quiet` was not specified. +--exists:: + + Check whether the given reference exists. Returns an exit code of 0 if + it does, 2 if it is missing, and 1 in case looking up the reference + failed with an error other than the reference being missing. + --abbrev[=]:: Abbreviate the object name. When using `--hash`, you do diff --git a/builtin/show-ref.c b/builtin/show-ref.c index 460f238a62..7aac525a87 100644 --- a/builtin/show-ref.c +++ b/builtin/show-ref.c @@ -2,7 +2,7 @@ #include "config.h" #include "gettext.h" #include "hex.h" -#include "refs.h" +#include "refs/refs-internal.h" #include "object-name.h" #include "object-store-ll.h" #include "object.h" @@ -18,6 +18,7 @@ static const char * const show_ref_usage[] = { " [-s | --hash[=]] [--abbrev[=]]\n" " [--] [...]"), N_("git show-ref --exclude-existing[=]"), + N_("git show-ref --exists "), NULL }; @@ -220,6 +221,41 @@ static int cmd_show_ref__patterns(const struct patterns_options *opts, return 0; } +static int cmd_show_ref__exists(const char **refs) +{ + struct strbuf unused_referent = STRBUF_INIT; + struct object_id unused_oid; + unsigned int unused_type; + int failure_errno = 0; + const char *ref; + int ret = 0; + + if (!refs || !*refs) + die("--exists requires a reference"); + ref = *refs++; + if (*refs) + die("--exists requires exactly one reference"); + + if (refs_read_raw_ref(get_main_ref_store(the_repository), ref, + &unused_oid, &unused_referent, &unused_type, + &failure_errno)) { + if (failure_errno == ENOENT) { + error(_("reference does not exist")); + ret = 2; + } else { + errno = failure_errno; + error_errno(_("failed to look up reference")); + ret = 1; + } + + goto out; + } + +out: + strbuf_release(&unused_referent); + return ret; +} + static int hash_callback(const struct option *opt, const char *arg, int unset) { struct show_one_options *opts = opt->value; @@ -249,10 +285,11 @@ int cmd_show_ref(int argc, const char **argv, const char *prefix) struct exclude_existing_options exclude_existing_opts = {0}; struct patterns_options patterns_opts = {0}; struct show_one_options show_one_opts = {0}; - int verify = 0; + int verify = 0, exists = 0; const struct option show_ref_options[] = { OPT_BOOL(0, "tags", &patterns_opts.tags_only, N_("only show tags (can be combined with heads)")), OPT_BOOL(0, "heads", &patterns_opts.heads_only, N_("only show heads (can be combined with tags)")), + OPT_BOOL(0, "exists", &exists, N_("check for reference existence without resolving")), OPT_BOOL(0, "verify", &verify, N_("stricter reference checking, " "requires exact ref path")), OPT_HIDDEN_BOOL('h', NULL, &patterns_opts.show_head, @@ -278,14 +315,16 @@ int cmd_show_ref(int argc, const char **argv, const char *prefix) argc = parse_options(argc, argv, prefix, show_ref_options, show_ref_usage, 0); - if ((!!exclude_existing_opts.enabled + !!verify) > 1) - die(_("only one of '%s' or '%s' can be given"), - "--exclude-existing", "--verify"); + if ((!!exclude_existing_opts.enabled + !!verify + !!exists) > 1) + die(_("only one of '%s', '%s' or '%s' can be given"), + "--exclude-existing", "--verify", "--exists"); if (exclude_existing_opts.enabled) return cmd_show_ref__exclude_existing(&exclude_existing_opts); else if (verify) return cmd_show_ref__verify(&show_one_opts, argv); + else if (exists) + return cmd_show_ref__exists(argv); else return cmd_show_ref__patterns(&patterns_opts, &show_one_opts, argv); } diff --git a/t/t1403-show-ref.sh b/t/t1403-show-ref.sh index f1e0388324..b50ae6fcf1 100755 --- a/t/t1403-show-ref.sh +++ b/t/t1403-show-ref.sh @@ -198,10 +198,71 @@ test_expect_success 'show-ref --verify with dangling ref' ' test_expect_success 'show-ref sub-modes are mutually exclusive' ' cat >expect <<-EOF && - fatal: only one of ${SQ}--exclude-existing${SQ} or ${SQ}--verify${SQ} can be given + fatal: only one of ${SQ}--exclude-existing${SQ}, ${SQ}--verify${SQ} or ${SQ}--exists${SQ} can be given EOF test_must_fail git show-ref --verify --exclude-existing 2>err && + test_cmp expect err && + + test_must_fail git show-ref --verify --exists 2>err && + test_cmp expect err && + + test_must_fail git show-ref --exclude-existing --exists 2>err && + test_cmp expect err +' + +test_expect_success '--exists with existing reference' ' + git show-ref --exists refs/heads/$GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME +' + +test_expect_success '--exists with missing reference' ' + test_expect_code 2 git show-ref --exists refs/heads/does-not-exist +' + +test_expect_success '--exists does not use DWIM' ' + test_expect_code 2 git show-ref --exists $GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME 2>err && + grep "reference does not exist" err +' + +test_expect_success '--exists with HEAD' ' + git show-ref --exists HEAD +' + +test_expect_success '--exists with bad reference name' ' + test_when_finished "git update-ref -d refs/heads/bad...name" && + new_oid=$(git rev-parse HEAD) && + test-tool ref-store main update-ref msg refs/heads/bad...name $new_oid $ZERO_OID REF_SKIP_REFNAME_VERIFICATION && + git show-ref --exists refs/heads/bad...name +' + +test_expect_success '--exists with arbitrary symref' ' + test_when_finished "git symbolic-ref -d refs/symref" && + git symbolic-ref refs/symref refs/heads/$GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME && + git show-ref --exists refs/symref +' + +test_expect_success '--exists with dangling symref' ' + test_when_finished "git symbolic-ref -d refs/heads/dangling" && + git symbolic-ref refs/heads/dangling refs/heads/does-not-exist && + git show-ref --exists refs/heads/dangling +' + +test_expect_success '--exists with nonexistent object ID' ' + test-tool ref-store main update-ref msg refs/heads/missing-oid $(test_oid 001) $ZERO_OID REF_SKIP_OID_VERIFICATION && + git show-ref --exists refs/heads/missing-oid +' + +test_expect_success '--exists with non-commit object' ' + tree_oid=$(git rev-parse HEAD^{tree}) && + test-tool ref-store main update-ref msg refs/heads/tree ${tree_oid} $ZERO_OID REF_SKIP_OID_VERIFICATION && + git show-ref --exists refs/heads/tree +' + +test_expect_success '--exists with directory fails with generic error' ' + cat >expect <<-EOF && + error: failed to look up reference: Is a directory + EOF + test_expect_code 1 git show-ref --exists refs/heads 2>err && test_cmp expect err '