t9300: factor out portable "head -c" replacement

diff --git a/t/t5551-http-fetch-smart.sh b/t/t5551-http-fetch-smart.sh
index 58207d88250f57d448f4e83baf2add3192cb9455..2f375eb94d528baefad038ff5b07baf0fe08d1fc 100755 (executable)
--- a/t/t5551-http-fetch-smart.sh
+++ b/t/t5551-http-fetch-smart.sh
@@ -282,5 +282,22 @@ test_expect_success EXPENSIVE 'http can handle enormous ref negotiation' '
        test_line_count = 100000 tags
 '
 
+test_expect_success 'custom http headers' '
+       test_must_fail git -c http.extraheader="x-magic-two: cadabra" \
+               fetch "$HTTPD_URL/smart_headers/repo.git" &&
+       git -c http.extraheader="x-magic-one: abra" \
+           -c http.extraheader="x-magic-two: cadabra" \
+           fetch "$HTTPD_URL/smart_headers/repo.git" &&
+       git update-index --add --cacheinfo 160000,$(git rev-parse HEAD),sub &&
+       git config -f .gitmodules submodule.sub.path sub &&
+       git config -f .gitmodules submodule.sub.url \
+               "$HTTPD_URL/smart_headers/repo.git" &&
+       git submodule init sub &&
+       test_must_fail git submodule update sub &&
+       git -c http.extraheader="x-magic-one: abra" \
+           -c http.extraheader="x-magic-two: cadabra" \
+               submodule update sub
+'
+
 stop_httpd
 test_done