Turn `git serve` into a test helper

The `git serve` built-in was introduced in ed10cb952d31 (serve:
introduce git-serve, 2018-03-15) as a backend to serve Git protocol v2,
probably originally intended to be spawned by `git upload-pack`.

However, in the version that the protocol v2 patches made it into core
Git, `git upload-pack` calls the `serve()` function directly instead of
spawning `git serve`; The only reason in life for `git serve` to survive
as a built-in command is to provide a way to test the protocol v2
functionality.

Meaning that it does not even have to be a built-in that is installed
with end-user facing Git installations, but it can be a test helper
instead.

Let's make it so.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 18 insertions, 14 deletions

diff --git a/t/t5701-git-serve.sh b/t/t5701-git-serve.sh
index fe45bf828d..ffb9613885 100755
--- a/t/t5701-git-serve.sh
+++ b/t/t5701-git-serve.sh
@@ -1,6 +1,6 @@
 #!/bin/sh
 
-test_description='test git-serve and server commands'
+test_description='test protocol v2 server commands'
 
 . ./test-lib.sh
 
@@ -14,7 +14,8 @@ test_expect_success 'test capability advertisement' '
 	0000
 	EOF
 
-	GIT_TEST_SIDEBAND_ALL=0 git serve --advertise-capabilities >out &&
+	GIT_TEST_SIDEBAND_ALL=0 test-tool serve-v2 \
+		--advertise-capabilities >out &&
 	test-tool pkt-line unpack <out >actual &&
 	test_cmp expect actual
 '
@@ -24,11 +25,11 @@ test_expect_success 'stateless-rpc flag does not list capabilities' '
 	test-tool pkt-line pack >in <<-EOF &&
 	0000
 	EOF
-	git serve --stateless-rpc >out <in &&
+	test-tool serve-v2 --stateless-rpc >out <in &&
 	test_must_be_empty out &&
 
 	# EOF
-	git serve --stateless-rpc >out &&
+	test-tool serve-v2 --stateless-rpc >out &&
 	test_must_be_empty out
 '
 
@@ -37,7 +38,7 @@ test_expect_success 'request invalid capability' '
 	foobar
 	0000
 	EOF
-	test_must_fail git serve --stateless-rpc 2>err <in &&
+	test_must_fail test-tool serve-v2 --stateless-rpc 2>err <in &&
 	test_i18ngrep "unknown capability" err
 '
 
@@ -46,7 +47,7 @@ test_expect_success 'request with no command' '
 	agent=git/test
 	0000
 	EOF
-	test_must_fail git serve --stateless-rpc 2>err <in &&
+	test_must_fail test-tool serve-v2 --stateless-rpc 2>err <in &&
 	test_i18ngrep "no command requested" err
 '
 
@@ -56,7 +57,7 @@ test_expect_success 'request invalid command' '
 	agent=git/test
 	0000
 	EOF
-	test_must_fail git serve --stateless-rpc 2>err <in &&
+	test_must_fail test-tool serve-v2 --stateless-rpc 2>err <in &&
 	test_i18ngrep "invalid command" err
 '
 
@@ -87,7 +88,7 @@ test_expect_success 'basics of ls-refs' '
 	0000
 	EOF
 
-	git serve --stateless-rpc <in >out &&
+	test-tool serve-v2 --stateless-rpc <in >out &&
 	test-tool pkt-line unpack <out >actual &&
 	test_cmp expect actual
 '
@@ -107,7 +108,7 @@ test_expect_success 'basic ref-prefixes' '
 	0000
 	EOF
 
-	git serve --stateless-rpc <in >out &&
+	test-tool serve-v2 --stateless-rpc <in >out &&
 	test-tool pkt-line unpack <out >actual &&
 	test_cmp expect actual
 '
@@ -127,7 +128,7 @@ test_expect_success 'refs/heads prefix' '
 	0000
 	EOF
 
-	git serve --stateless-rpc <in >out &&
+	test-tool serve-v2 --stateless-rpc <in >out &&
 	test-tool pkt-line unpack <out >actual &&
 	test_cmp expect actual
 '
@@ -148,7 +149,7 @@ test_expect_success 'peel parameter' '
 	0000
 	EOF
 
-	git serve --stateless-rpc <in >out &&
+	test-tool serve-v2 --stateless-rpc <in >out &&
 	test-tool pkt-line unpack <out >actual &&
 	test_cmp expect actual
 '
@@ -169,7 +170,7 @@ test_expect_success 'symrefs parameter' '
 	0000
 	EOF
 
-	git serve --stateless-rpc <in >out &&
+	test-tool serve-v2 --stateless-rpc <in >out &&
 	test-tool pkt-line unpack <out >actual &&
 	test_cmp expect actual
 '
@@ -189,7 +190,7 @@ test_expect_success 'sending server-options' '
 	0000
 	EOF
 
-	git serve --stateless-rpc <in >out &&
+	test-tool serve-v2 --stateless-rpc <in >out &&
 	test-tool pkt-line unpack <out >actual &&
 	test_cmp expect actual
 '
@@ -204,7 +205,10 @@ test_expect_success 'unexpected lines are not allowed in fetch request' '
 	0000
 	EOF
 
-	test_must_fail git -C server serve --stateless-rpc <in >/dev/null 2>err &&
+	(
+		cd server &&
+		test_must_fail test-tool serve-v2 --stateless-rpc
+	) <in >/dev/null 2>err &&
 	grep "unexpected line: .this-is-not-a-command." err
 '