moved parameter_binder from member to parameter to bind, execute and fetch methods

test/orm/sql/StatementCacheTest.cpp

@@ -17,12 +17,12 @@ TEST_CASE("Test statement cache", "[statement][cache]") {
   backend_provider::instance().register_backend("noop", std::make_unique<orm::test_backend_service>());
 
   connection_pool pool("noop://noop.db", 4);
-  statement_cache cache(pool, 4);
+  statement_cache cache(pool, 2);
 
   query_context ctx;
   ctx.sql = "SELECT * FROM person";
 
-  REQUIRE(cache.capacity() == 4);
+  REQUIRE(cache.capacity() == 2);
   REQUIRE(cache.empty());
 
   auto result = cache.acquire(ctx);
@@ -30,7 +30,25 @@ TEST_CASE("Test statement cache", "[statement][cache]") {
 
   REQUIRE(cache.size() == 1);
   REQUIRE(!cache.empty());
-  REQUIRE(cache.capacity() == 4);
+  REQUIRE(cache.capacity() == 2);
 
   const auto stmt = result.value();
+
+  ctx.sql = "SELECT title FROM book";
+
+  result = cache.acquire(ctx);
+  REQUIRE(result);
+
+  REQUIRE(cache.size() == 2);
+  REQUIRE(!cache.empty());
+  REQUIRE(cache.capacity() == 2);
+
+  ctx.sql = "SELECT name FROM author";
+
+  result = cache.acquire(ctx);
+  REQUIRE(result);
+
+  REQUIRE(cache.size() == 2);
+  REQUIRE(!cache.empty());
+  REQUIRE(cache.capacity() == 2);
 }