Merge branch 'tb/filter-alternate-refs'

When pushing into a repository that borrows its objects from an
alternate object store, "git receive-pack" that responds to the
push request on the other side lists the tips of refs in the
alternate to reduce the amount of objects transferred.  This
sometimes is detrimental when the number of refs in the alternate
is absurdly large, in which case the bandwidth saved in potentially
fewer objects transferred is wasted in excessively large ref
advertisement.  The alternate refs that are advertised are now
configurable with a pair of configuration variables.

* tb/filter-alternate-refs:
  transport.c: introduce core.alternateRefsPrefixes
  transport.c: introduce core.alternateRefsCommand
  transport.c: extract 'fill_alternate_refs_command'
  transport: drop refnames from for_each_alternate_ref

1 files changed, 41 insertions, 0 deletions

diff --git a/t/t5410-receive-pack-alternates.sh b/t/t5410-receive-pack-alternates.sh
new file mode 100755
index 0000000000..457c20c2a5
--- /dev/null
+++ b/t/t5410-receive-pack-alternates.sh
@@ -0,0 +1,41 @@
+#!/bin/sh
+
+test_description='git receive-pack with alternate ref filtering'
+
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+	test_commit base &&
+	git clone -s --bare . fork &&
+	git checkout -b public/branch master &&
+	test_commit public &&
+	git checkout -b private/branch master &&
+	test_commit private
+'
+
+extract_haves () {
+	depacketize | perl -lne '/^(\S+) \.have/ and print $1'
+}
+
+test_expect_success 'with core.alternateRefsCommand' '
+	write_script fork/alternate-refs <<-\EOF &&
+		git --git-dir="$1" for-each-ref \
+			--format="%(objectname)" \
+			refs/heads/public/
+	EOF
+	test_config -C fork core.alternateRefsCommand alternate-refs &&
+	git rev-parse public/branch >expect &&
+	printf "0000" | git receive-pack fork >actual &&
+	extract_haves <actual >actual.haves &&
+	test_cmp expect actual.haves
+'
+
+test_expect_success 'with core.alternateRefsPrefixes' '
+	test_config -C fork core.alternateRefsPrefixes "refs/heads/private" &&
+	git rev-parse private/branch >expect &&
+	printf "0000" | git receive-pack fork >actual &&
+	extract_haves <actual >actual.haves &&
+	test_cmp expect actual.haves
+'
+
+test_done