added assignment from value, conversion to database_type and appropriate tests

test/core/utils/IdentifierTest.cpp

@@ -2,6 +2,7 @@
 
 #include "matador/utils/identifier.hpp"
 #include "matador/utils/default_type_traits.hpp"
+#include "matador/utils/value.hpp"
 
 using namespace matador::utils;
 
@@ -279,3 +280,87 @@ TEST_CASE("identifier as() and convert() behave consistently for same integer ty
   REQUIRE(conv_u64.is_ok());
   REQUIRE(*conv_u64 == 77);
 }
+
+TEST_CASE("identifier assign from value", "[utils][identifier][assign]") {
+  identifier id;
+
+  value v1{int32_t{17}};
+  const auto r1 = id.assign(v1);
+  REQUIRE(r1.is_ok());
+  REQUIRE(id.is_integer());
+  REQUIRE(id.str() == "17");
+
+  value v2{std::string{"abc"}};
+  const auto r2 = id.assign(v2);
+  REQUIRE(r2.is_ok());
+  REQUIRE(id.is_varchar());
+  REQUIRE(id.str() == "abc");
+
+  value v3{basic_type::Double, 0};
+  const auto r3 = id.assign(v3);
+  REQUIRE(r3.is_error());
+}
+
+TEST_CASE("identifier assign from value with exact type mapping", "[utils][identifier][assign]") {
+  identifier id;
+
+  SECTION("integer types") {
+    value v{int16_t{12}};
+    const auto r = id.assign(v);
+    REQUIRE(r.is_ok());
+    REQUIRE(id.is_integer());
+    REQUIRE(id.str() == "12");
+  }
+
+  SECTION("string types") {
+    value v{std::string{"abc"}};
+    const auto r = id.assign(v);
+    REQUIRE(r.is_ok());
+    REQUIRE(id.is_varchar());
+    REQUIRE(id.str() == "abc");
+  }
+
+  SECTION("null") {
+    value v{basic_type::Null, 0};
+    const auto r = id.assign(v);
+    REQUIRE(r.is_ok());
+    REQUIRE(id.is_null());
+  }
+}
+
+TEST_CASE("identifier::to_database_type converts internal value to database_type", "[identifier]") {
+  SECTION("null identifier becomes nullptr") {
+    identifier id{nullptr};
+
+    const auto db_value = id.to_database_type();
+
+    REQUIRE(std::holds_alternative<std::nullptr_t>(db_value));
+  }
+
+  SECTION("signed integral identifier becomes same signed database type") {
+    identifier id{int32_t{42}};
+
+    const auto db_value = id.to_database_type();
+
+    REQUIRE(std::holds_alternative<int32_t>(db_value));
+    REQUIRE(std::get<int32_t>(db_value) == 42);
+  }
+
+  SECTION("unsigned integral identifier becomes same unsigned database type") {
+    identifier id{uint64_t{123456789ULL}};
+
+    const auto db_value = id.to_database_type();
+
+    REQUIRE(std::holds_alternative<uint64_t>(db_value));
+    REQUIRE(std::get<uint64_t>(db_value) == 123456789ULL);
+  }
+
+  SECTION("string identifier becomes std::string database type") {
+    identifier id{std::string{"customer_1"}};
+
+    const auto db_value = id.to_database_type();
+
+    REQUIRE(std::holds_alternative<std::string>(db_value));
+    REQUIRE(std::get<std::string>(db_value) == "customer_1");
+  }
+}