Minor code cleanup

lib/serializer/ESerializationVersion.h

@@ -0,0 +1,39 @@
+/*
+ * ESerializationVersion.h, part of VCMI engine
+ *
+ * Authors: listed in file AUTHORS in main folder
+ *
+ * License: GNU General Public License v2.0 or later
+ * Full text of license available in license.txt file, in main folder
+ *
+ */
+#pragma once
+
+/// This enumeration controls save compatibility support.
+/// - 'MINIMAL' represents the oldest supported version counter. A saved game can be loaded if its version is at least 'MINIMAL'.
+/// - 'CURRENT' represents the current save version. Saved games are created using the 'CURRENT' version.
+///
+/// To make a save-breaking change:
+/// - change 'MINIMAL' to a value higher than 'CURRENT'
+/// - remove all keys in enumeration between 'MINIMAL' and 'CURRENT' as well as all their usage (will be detected by compiler)
+/// - change 'CURRENT' to 'CURRENT = MINIMAL'
+///
+/// To make a non-breaking change:
+/// - add new enumeration value before 'CURRENT'
+/// - change 'CURRENT' to 'CURRENT = NEW_TEST_KEY'.
+///
+/// To check for version in serialize() call use form
+/// if (h.version >= Handler::Version::NEW_TEST_KEY)
+///     h & newKey; // loading/saving save of a new version
+/// else
+///     newKey = saneDefaultValue; // loading of old save
+enum class ESerializationVersion : int32_t
+{
+	NONE = 0,
+
+	MINIMAL = 831,
+	RELEASE_143, // 832 +text container in campaigns, +starting hero in RMG options
+	HAS_EXTRA_OPTIONS, // 833 +extra options struct as part of startinfo
+
+	CURRENT = HAS_EXTRA_OPTIONS
+};