CoreStore v7.1.0 Release Notes

Release Date: 2020-03-27 // 10 months ago
  • โšก๏ธ Maintenance updates

    • ๐Ÿ‘ Xcode 11.4 and Swift 5.2 support

    ๐Ÿ†• New Property Wrappers syntax

    โช โš ๏ธ These changes apply only to CoreStoreObject subclasses, notNSManagedObjects.

    ๐Ÿฑ โ€ผ๏ธ Please take note of the warnings below before migrating or else the model's hash might change.

    ๐Ÿ‘ If conversion is too risky, the current Value.Required, Value.Optional, Transformable.Required, Transformable.Optional, Relationship.ToOne, Relationship.ToManyOrdered, and Relationship.ToManyUnordered will all be supported for while so you can opt to use them as is for now.

    ๐Ÿฑ โ€ผ๏ธ If you are confident about conversion, I cannot stress this enough, but please make sure to set your schema's VersionLock before converting!

    @Field.Stored (replacement for non "transient" Value.Required and Value.Optional)

    class Person: CoreStoreObject { @Field.Stored("title") var title: String = "Mr."@Field.Stored("nickname") var nickname: String?}
    

    ๐Ÿฑ โš ๏ธ Only Value.Required and Value.Optional that are NOT transient values can be converted to Field.Stored.
    ๐Ÿฑ โš ๏ธ When converting, make sure that all parameters, including the default values, are exactly the same or else the model's hash might change.

    @Field.Virtual (replacement for "transient" versions of Value.Required andValue.Optional)

    class Animal: CoreStoreObject { @Field.Virtual( "pluralName", customGetter: { (object, field) inreturn object.$species.value + "s" } ) var pluralName: [email protected]("species") var species: String = ""}
    

    ๐Ÿฑ โš ๏ธ Only Value.Required and Value.Optional that ARE transient values can be converted to Field.Virtual.
    ๐Ÿฑ โš ๏ธ When converting, make sure that all parameters, including the default values, are exactly the same or else the model's hash might change.

    ๐Ÿ‘ @Field.Coded (replacement for Transformable.Required andTransformable.Optional, with additional support for custom encoders such as JSON)

    class Person: CoreStoreObject { @Field.Coded( "bloodType", coder: { encode: { $0.toData() }, decode: { BloodType(fromData: $0) } } ) var bloodType: BloodType?}
    

    ๐Ÿฑ โ€ผ๏ธ The current Transformable.Required and Transformable.Optional mechanism have no safe conversion to @Field.Coded. Please use @Field.Coded only for newly added attributes.

    @Field.Relationship (replacement for Relationship.ToOne, Relationship.ToManyOrdered, and Relationship.ToManyUnordered)

    class Pet: CoreStoreObject { @Field.Relationship("master") var master: Person?}class Person: CoreStoreObject { @Field.Relationship("pets", inverse: \.$master) var pets: Set\<Pet\>}
    

    ๐Ÿฑ โš ๏ธ Relationship.ToOne<T> maps to T?, Relationship.ToManyOrdered maps to Array<T>, and Relationship.ToManyUnordered maps to Set<T>
    ๐Ÿฑ โš ๏ธ When converting, make sure that all parameters, including the default values, are exactly the same or else the model's hash might change.

    Usage

    Before diving into the properties themselves, note that they will effectively force you to use a different syntax for queries:

    • Before: From<Person>.where(\.title == "Mr.")
    • After: From<Person>.where(\.$title == "Mr.")

    There are a several advantages to using these Property Wrappers:

    • ๐Ÿ‘€ The @propertyWrapper versions will be magnitudes performant and efficient than their current implementations. Currently Mirror reflection is used a lot to inject the NSManagedObject reference into the properties. With @propertyWrappers this will be synthesized by the compiler for us. (See apple/swift#25884)
    • The @propertyWrapper versions, being structs, will give the compiler a lot more room for optimizations which were not possible before due to the need for mutable classes.
    • You can now add computed properties that are accessible to both ObjectSnapshots and ObjectPublishers by declaring them as @Field.Virtual. Note that for ObjectSnapshots, the computed values are evaluated only once during creation and are not recomputed afterwards.

    The only disadvantage will be:

    • โšก๏ธ You need to update your code by hand to migrate to the new @propertyWrappers
      (But the legacy ones will remain available for quite a while, so while it is recommended to migrate soon, no need to panic)