public void addField(@Nonnull String ownerName, @Nullable String desc, @Nonnull String oldName, @Nonnull String newName) {
		if (Objects.equals(oldName, newName)) return; // Skip identity mappings
		fields.computeIfAbsent(ownerName, n -> new ArrayList<>())
				.add(new FieldMapping(ownerName, oldName, desc, newName));
	}
@param ownerName
		Name of class defining the field.
@param desc
		Descriptor type of the field.
@param oldName
		Pre-mapping field name.
@param newName
		Post-mapping field name.
recaf-core/src/main/java/software/coley/recaf/services/mapping/IntermediateMappings.java