tests: Fix tools::is_hdd unit tests

Correct the unit tests for tools::is_hdd to avoid making assumptions
about the configuration of a particular device based solely on the
value of the __GLIBC__ preprocessor flag. Instead, rely on the
test invoker to provide paths for devices of specific types via
the process environment, thereby avoiding faulty assumptions and
improving the specificity of test assertions. To ensure appropriate
devices exist, add a script, tests/create_test_disks.sh, which
configures loopback devices mirroring relevant configurations.

1 files changed, 28 insertions, 9 deletions

diff --git a/tests/unit_tests/is_hdd.cpp b/tests/unit_tests/is_hdd.cpp
index 040af4f47..55f759ed9 100644
--- a/tests/unit_tests/is_hdd.cpp
+++ b/tests/unit_tests/is_hdd.cpp
@@ -1,17 +1,36 @@
 #include "common/util.h"
+#include <cstdlib>
 #include <string>
 #include <gtest/gtest.h>
+#include <boost/optional/optional_io.hpp> /* required to output boost::optional in assertions */
+
+#ifndef GTEST_SKIP
+#include <iostream>
+#define SKIP_TEST(reason) do {std::cerr << "Skipping test: " << reason << std::endl; return;} while(0)
+#else
+#define SKIP_TEST(reason) GTEST_SKIP() << reason
+#endif
 
 #if defined(__GLIBC__)
-TEST(is_hdd, linux_os_root)
-{
-  std::string path = "/";
-  EXPECT_TRUE(tools::is_hdd(path.c_str()) != boost::none);
+TEST(is_hdd, rotational_drive) {
+  const char *hdd = std::getenv("MONERO_TEST_DEVICE_HDD");
+  if (hdd == nullptr)
+    SKIP_TEST("No rotational disk device configured");
+  EXPECT_EQ(tools::is_hdd(hdd), boost::optional<bool>(true));
 }
-#else
-TEST(is_hdd, unknown_os)
-{
-  std::string path = "";
-  EXPECT_FALSE(tools::is_hdd(path.c_str()) != boost::none);
+
+TEST(is_hdd, ssd) {
+  const char *ssd = std::getenv("MONERO_TEST_DEVICE_SSD");
+  if (ssd == nullptr)
+    SKIP_TEST("No SSD device configured");
+  EXPECT_EQ(tools::is_hdd(ssd), boost::optional<bool>(false));
+}
+
+TEST(is_hdd, unknown_attrs) {
+  EXPECT_EQ(tools::is_hdd("/dev/null"), boost::none);
 }
 #endif
+TEST(is_hdd, stability)
+{
+  EXPECT_NO_THROW(tools::is_hdd(""));
+}