utils: Add unit tests

Ensure utils.hpp can build on its own, and add some unit tests.

Change-Id: Ia147b699105ff4497d9226630ef19e57d91de3c3
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/test/utils_test.cpp b/test/utils_test.cpp
new file mode 100644
index 0000000..c1f15f7
--- /dev/null
+++ b/test/utils_test.cpp
@@ -0,0 +1,97 @@
+#include "../utils.hpp"
+
+#include <gtest/gtest.h>
+
+using namespace sdbusplus::message::variant_ns;
+using namespace phosphor::inventory::manager;
+using namespace std::string_literals;
+
+TEST(UtilsTest, TestVariantVisitor)
+{
+    variant<int, std::string> ib1(100);
+    auto converted1 = convertVariant<variant<int>>(ib1);
+    EXPECT_TRUE(get<int>(converted1) == 100);
+
+    variant<int, std::string> ib2(100);
+    EXPECT_THROW(convertVariant<variant<std::string>>(ib2), std::runtime_error);
+}
+
+TEST(UtilsTest, TestCompareFirst)
+{
+    auto c = compareFirst(std::less<int>());
+    auto p1 = std::make_pair(1, 2);
+    auto p2 = std::make_pair(3, 4);
+
+    EXPECT_TRUE(c(p1, p2));
+    EXPECT_TRUE(c(1, p2));
+    EXPECT_TRUE(c(p1, 2));
+    EXPECT_FALSE(c(p2, p1));
+    EXPECT_FALSE(c(p2, 1));
+    EXPECT_FALSE(c(2, p1));
+
+    auto p3 = std::make_pair(1, 100);
+    auto p4 = std::make_pair(1, 200);
+
+    EXPECT_FALSE(c(p3, p4));
+    EXPECT_FALSE(c(1, p4));
+    EXPECT_TRUE(c(p3, 2));
+    EXPECT_FALSE(c(p4, p3));
+    EXPECT_FALSE(c(p4, 1));
+    EXPECT_FALSE(c(2, p3));
+}
+
+TEST(UtilsTest, TestRelPathComparePrefix)
+{
+    auto s1 = "prefixfoo"s;
+    auto s2 = "prefixbar"s;
+    RelPathCompare comp("prefix");
+
+    EXPECT_TRUE(comp(s2, s1));
+    EXPECT_FALSE(comp(s1, s2));
+
+    auto s3 = "bar"s;
+    auto s4 = "foo"s;
+
+    EXPECT_FALSE(comp(s4, s3));
+    EXPECT_TRUE(comp(s3, s4));
+
+    auto s5 = "prefixbar"s;
+    auto s6 = "foo"s;
+
+    EXPECT_FALSE(comp(s6, s5));
+    EXPECT_TRUE(comp(s5, s6));
+
+    auto s7 = "bar"s;
+    auto s8 = "prefixfoo"s;
+
+    EXPECT_FALSE(comp(s8, s7));
+    EXPECT_TRUE(comp(s7, s8));
+}
+
+TEST(UtilsTest, TestRelPathCompareNoPrefix)
+{
+    auto s1 = "prefixfoo"s;
+    auto s2 = "prefixbar"s;
+    RelPathCompare comp("");
+
+    EXPECT_TRUE(comp(s2, s1));
+    EXPECT_FALSE(comp(s1, s2));
+
+    auto s3 = "bar"s;
+    auto s4 = "foo"s;
+
+    EXPECT_FALSE(comp(s4, s3));
+    EXPECT_TRUE(comp(s3, s4));
+
+    auto s5 = "prefixbar"s;
+    auto s6 = "foo"s;
+
+    EXPECT_TRUE(comp(s6, s5));
+    EXPECT_FALSE(comp(s5, s6));
+
+    auto s7 = "bar"s;
+    auto s8 = "prefixfoo"s;
+
+    EXPECT_FALSE(comp(s8, s7));
+    EXPECT_TRUE(comp(s7, s8));
+}