i5700: add interop test for protocol transition

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/interop/i5700-protocol-transition.sh

@@ -0,0 +1,68 @@
+#!/bin/sh
+
+VERSION_A=.
+VERSION_B=v2.0.0
+
+: ${LIB_GIT_DAEMON_PORT:=5700}
+LIB_GIT_DAEMON_COMMAND='git.b daemon'
+
+test_description='clone and fetch by client who is trying to use a new protocol'
+. ./interop-lib.sh
+. "$TEST_DIRECTORY"/lib-git-daemon.sh
+
+start_git_daemon --export-all
+
+repo=$GIT_DAEMON_DOCUMENT_ROOT_PATH/repo
+
+test_expect_success "create repo served by $VERSION_B" '
+	git.b init "$repo" &&
+	git.b -C "$repo" commit --allow-empty -m one
+'
+
+test_expect_success "git:// clone with $VERSION_A and protocol v1" '
+	GIT_TRACE_PACKET=1 git.a -c protocol.version=1 clone "$GIT_DAEMON_URL/repo" child 2>log &&
+	git.a -C child log -1 --format=%s >actual &&
+	git.b -C "$repo" log -1 --format=%s >expect &&
+	test_cmp expect actual &&
+	grep "version=1" log
+'
+
+test_expect_success "git:// fetch with $VERSION_A and protocol v1" '
+	git.b -C "$repo" commit --allow-empty -m two &&
+	git.b -C "$repo" log -1 --format=%s >expect &&
+
+	GIT_TRACE_PACKET=1 git.a -C child -c protocol.version=1 fetch 2>log &&
+	git.a -C child log -1 --format=%s FETCH_HEAD >actual &&
+
+	test_cmp expect actual &&
+	grep "version=1" log &&
+	! grep "version 1" log
+'
+
+stop_git_daemon
+
+test_expect_success "create repo served by $VERSION_B" '
+	git.b init parent &&
+	git.b -C parent commit --allow-empty -m one
+'
+
+test_expect_success "file:// clone with $VERSION_A and protocol v1" '
+	GIT_TRACE_PACKET=1 git.a -c protocol.version=1 clone --upload-pack="git.b upload-pack" parent child2 2>log &&
+	git.a -C child2 log -1 --format=%s >actual &&
+	git.b -C parent log -1 --format=%s >expect &&
+	test_cmp expect actual &&
+	! grep "version 1" log
+'
+
+test_expect_success "file:// fetch with $VERSION_A and protocol v1" '
+	git.b -C parent commit --allow-empty -m two &&
+	git.b -C parent log -1 --format=%s >expect &&
+
+	GIT_TRACE_PACKET=1 git.a -C child2 -c protocol.version=1 fetch --upload-pack="git.b upload-pack" 2>log &&
+	git.a -C child2 log -1 --format=%s FETCH_HEAD >actual &&
+
+	test_cmp expect actual &&
+	! grep "version 1" log
+'
+
+test_done