t0052: add simple-ipc tests and t/helper/test-simple-ipc tool

Create t0052-simple-ipc.sh with unit tests for the "simple-ipc" mechanism.

Create t/helper/test-simple-ipc test tool to exercise the "simple-ipc"
functions.

When the tool is invoked with "run-daemon", it runs a server to listen
for "simple-ipc" connections on a test socket or named pipe and
responds to a set of commands to exercise/stress the communication
setup.

When the tool is invoked with "start-daemon", it spawns a "run-daemon"
command in the background and waits for the server to become ready
before exiting.  (This helps make unit tests in t0052 more predictable
and avoids the need for arbitrary sleeps in the test script.)

The tool also has a series of client "send" commands to send commands
and data to a server instance.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/t/helper/test-tool.h b/t/helper/test-tool.h
index a6470ff62c..564eb3c8e9 100644
--- a/t/helper/test-tool.h
+++ b/t/helper/test-tool.h
@@ -54,6 +54,7 @@ int cmd__sha1(int argc, const char **argv);
 int cmd__oid_array(int argc, const char **argv);
 int cmd__sha256(int argc, const char **argv);
 int cmd__sigchain(int argc, const char **argv);
+int cmd__simple_ipc(int argc, const char **argv);
 int cmd__strcmp_offset(int argc, const char **argv);
 int cmd__string_list(int argc, const char **argv);
 int cmd__submodule_config(int argc, const char **argv);