fetch: do not list refs if fetching only hashes

If only hash literals are given on a "git fetch" command-line, tag
following is not requested, and the fetch is done using protocol v2, a
list of refs is not required from the remote. Therefore, optimize by
invoking transport_get_remote_refs() only if we need the refs.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/fetch.c b/builtin/fetch.c
index 0696abfc2a158baa3177fa9e71e2c16bc64655a4..4c4f8fa1944d4ded0330bbc316b697acfd4f046d 100644 (file)
--- a/builtin/fetch.c
+++ b/builtin/fetch.c
@@ -1175,6 +1175,7 @@ static int do_fetch(struct transport *transport,
        int retcode = 0;
        const struct ref *remote_refs;
        struct argv_array ref_prefixes = ARGV_ARRAY_INIT;
+       int must_list_refs = 1;
 
        if (tags == TAGS_DEFAULT) {
                if (transport->remote->fetch_tags == 2)
@@ -1190,17 +1191,36 @@ static int do_fetch(struct transport *transport,
                        goto cleanup;
        }
 
-       if (rs->nr)
+       if (rs->nr) {
+               int i;
+
                refspec_ref_prefixes(rs, &ref_prefixes);
-       else if (transport->remote && transport->remote->fetch.nr)
+
+               /*
+                * We can avoid listing refs if all of them are exact
+                * OIDs
+                */
+               must_list_refs = 0;
+               for (i = 0; i < rs->nr; i++) {
+                       if (!rs->items[i].exact_sha1) {
+                               must_list_refs = 1;
+                               break;
+                       }
+               }
+       } else if (transport->remote && transport->remote->fetch.nr)
                refspec_ref_prefixes(&transport->remote->fetch, &ref_prefixes);
 
-       if (ref_prefixes.argc &&
-           (tags == TAGS_SET || (tags == TAGS_DEFAULT))) {
-               argv_array_push(&ref_prefixes, "refs/tags/");
+       if (tags == TAGS_SET || tags == TAGS_DEFAULT) {
+               must_list_refs = 1;
+               if (ref_prefixes.argc)
+                       argv_array_push(&ref_prefixes, "refs/tags/");
        }
 
-       remote_refs = transport_get_remote_refs(transport, &ref_prefixes);
+       if (must_list_refs)
+               remote_refs = transport_get_remote_refs(transport, &ref_prefixes);
+       else
+               remote_refs = NULL;
+
        argv_array_clear(&ref_prefixes);
 
        ref_map = get_ref_map(transport->remote, remote_refs, rs,

diff --git a/t/t5551-http-fetch-smart.sh b/t/t5551-http-fetch-smart.sh
index 771f36f9ff473d31507af374f1c96fac03192048..12b339d239e827866d666369da3801cd69b0432d 100755 (executable)
--- a/t/t5551-http-fetch-smart.sh
+++ b/t/t5551-http-fetch-smart.sh
@@ -381,6 +381,21 @@ test_expect_success 'using fetch command in remote-curl updates refs' '
        test_cmp expect actual
 '
 
+test_expect_success 'fetch by SHA-1 without tag following' '
+       SERVER="$HTTPD_DOCUMENT_ROOT_PATH/server" &&
+       rm -rf "$SERVER" client &&
+
+       git init "$SERVER" &&
+       test_commit -C "$SERVER" foo &&
+
+       git clone $HTTPD_URL/smart/server client &&
+
+       test_commit -C "$SERVER" bar &&
+       git -C "$SERVER" rev-parse bar >bar_hash &&
+       git -C client -c protocol.version=0 fetch \
+               --no-tags origin $(cat bar_hash)
+'
+
 test_expect_success 'GIT_REDACT_COOKIES redacts cookies' '
        rm -rf clone &&
        echo "Set-Cookie: Foo=1" >cookies &&

diff --git a/t/t5702-protocol-v2.sh b/t/t5702-protocol-v2.sh
index e32b5b4e3e2dadb44553ef4627fee817c56d752b..b82b5f8f7e8845ad84156e4b395c5a89156a293a 100755 (executable)
--- a/t/t5702-protocol-v2.sh
+++ b/t/t5702-protocol-v2.sh
@@ -79,6 +79,19 @@ test_expect_success 'fetch with git:// using protocol v2' '
        grep "fetch< version 2" log
 '
 
+test_expect_success 'fetch by hash without tag following with protocol v2 does not list refs' '
+       test_when_finished "rm -f log" &&
+
+       test_commit -C "$daemon_parent" two_a &&
+       git -C "$daemon_parent" rev-parse two_a >two_a_hash &&
+
+       GIT_TRACE_PACKET="$(pwd)/log" git -C daemon_child -c protocol.version=2 \
+               fetch --no-tags origin $(cat two_a_hash) &&
+
+       grep "fetch< version 2" log &&
+       ! grep "fetch> command=ls-refs" log
+'
+
 test_expect_success 'pull with git:// using protocol v2' '
        test_when_finished "rm -f log" &&