test: test GIT_CURL_VERBOSE=1 shows an error

This tests GIT_CURL_VERBOSE shows an error when an URL returns 500. This
exercises the code in remote_curl.

Signed-off-by: Masaya Suzuki <masayasuzuki@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/t/t5581-http-curl-verbose.sh b/t/t5581-http-curl-verbose.sh
new file mode 100755
index 0000000..cd9283e
--- /dev/null
+++ b/t/t5581-http-curl-verbose.sh
@@ -0,0 +1,28 @@
+#!/bin/sh
+
+test_description='test GIT_CURL_VERBOSE'
+. ./test-lib.sh
+. "$TEST_DIRECTORY"/lib-httpd.sh
+start_httpd
+
+test_expect_success 'setup repository' '
+	mkdir "$HTTPD_DOCUMENT_ROOT_PATH/repo.git" &&
+	git -C "$HTTPD_DOCUMENT_ROOT_PATH/repo.git" --bare init &&
+	git config push.default matching &&
+	echo content >file &&
+	git add file &&
+	git commit -m one &&
+	git remote add public "$HTTPD_DOCUMENT_ROOT_PATH/repo.git" &&
+	git push public master:master
+'
+
+test_expect_success 'failure in git-upload-pack is shown' '
+	test_might_fail env GIT_CURL_VERBOSE=1 \
+		git clone "$HTTPD_URL/error_git_upload_pack/smart/repo.git" \
+		2>curl_log &&
+	grep "< HTTP/1.1 500 Intentional Breakage" curl_log
+'
+
+stop_httpd
+
+test_done