Fix compilation and add tests

libstuff/SQuery.h

@@ -8,6 +8,7 @@
 using namespace std;
 
 class SQuery {
-    using QuerySerializable = variant<const char*, string&, int, unsigned, uint64_t, int64_t, double>;
+public:
+    using QuerySerializable = variant<const char*, string, int, unsigned, uint64_t, int64_t, double>;
     static string prepare(const string& query, const map<string, QuerySerializable>& params);
 };

test/tests/SQueryTest.cpp

@@ -0,0 +1,20 @@
+#include <libstuff/SQuery.h>
+#include <test/lib/BedrockTester.h>
+
+struct SQueryTest : tpunit::TestFixture {
+    SQueryTest() : tpunit::TestFixture(true, "SQuery",
+        TEST(SQueryTest::testPrepare)
+        )
+    {}
+
+    void testPrepare() {
+        // single param
+        ASSERT_EQUAL(SQuery::prepare("SELECT * FROM accounts WHERE accountID = {accountID};", {{"accountID", 42}}), "SELECT * FROM accounts WHERE accountID = 42;");
+
+        // multiple params
+        ASSERT_EQUAL(SQuery::prepare("SELECT * FROM reports WHERE accountID = {accountID} AND reportID = {reportID};", {{"accountID", 42}, {"reportID", 52}}), "SELECT * FROM reports WHERE accountID = 42 AND reportID = 52;");
+
+        // multiple params, multiple instances
+        ASSERT_EQUAL(SQuery::prepare("SELECT * FROM reportActions WHERE action == {actionCreated} OR (action != {actionCreated} AND created < {timestamp});", {{"actionCreated", "CREATED"}, {"timestamp", "2024-01-01 12:00:00"}}), "SELECT * FROM reportActions WHERE action == 'CREATED' OR (action != 'CREATED' AND created < '2024-01-01 12:00:00');");
+    }
+} __SQueryTest;