When you encounter the error message “entity was modified, but it won’t be updated because the property is immutable,” it means that you are trying to modify a property of an entity that cannot be changed once it is set. This typically occurs when you try to update a property that has been designated as immutable, meaning its value cannot be altered after creation.
To illustrate this, let’s consider an example. Suppose we have a “User” entity with properties such as “id”, “name”, and “email”. If the “id” property is immutable, you cannot modify its value once it is set during the entity’s creation. Therefore, any attempt to update the “id” property would result in the mentioned error message.
Here’s a code snippet demonstrating the scenario:
const user = new User();
user.id = 123; // Immutable property - cannot be modified
// Causes the error "entity was modified, but it won't be updated because the property is immutable"
user.id = 456;
In the above example, the initial assignment of the “id” property is allowed. However, any subsequent attempts to modify it will throw the error, as the property is marked as immutable.