Add unit tests for file body

File body needs some unit tests for managing the move constructors.

Tested: Unit tests pass.

Change-Id: Ia640aec75a6f3f85640a50f5dd492638871f9eca
Signed-off-by: Ed Tanous <ed@tanous.net>
diff --git a/test/http/file_test_utilities.hpp b/test/http/file_test_utilities.hpp
new file mode 100644
index 0000000..073a074
--- /dev/null
+++ b/test/http/file_test_utilities.hpp
@@ -0,0 +1,19 @@
+#pragma once
+#include <filesystem>
+#include <string>
+#include <string_view>
+
+#include <gtest/gtest.h>
+
+inline std::string makeFile(std::string_view sampleData)
+{
+    std::filesystem::path path = std::filesystem::temp_directory_path();
+    path /= "bmcweb_http_response_test_XXXXXXXXXXX";
+    std::string stringPath = path.string();
+    int fd = mkstemp(stringPath.data());
+    EXPECT_GT(fd, 0);
+    EXPECT_EQ(write(fd, sampleData.data(), sampleData.size()),
+              sampleData.size());
+    close(fd);
+    return stringPath;
+}