WIP: readme

Sources/DataStack+Transaction.swift

@@ -32,10 +32,10 @@ import CoreData
 public extension DataStack {
     
     /**
-     Performs a transaction asynchronously where `NSManagedObject` creates, updates, and deletes can be made. The changes are commited automatically after the `task` closure returns. On success, the value returned from closure will be the wrapped as `TransactionResult.success(userInfo: T)` in the `completion`'s `TransactionResult<T>`. Any errors thrown from inside the `task` will be reported as `TransactionResult.failure(error: Error)`. To cancel/rollback changes, call `transaction.cancel()`, which throws a `CoreStoreError.userCancelled`.
+     Performs a transaction asynchronously where `NSManagedObject` or `CoreStoreObject` creates, updates, and deletes can be made. The changes are commited automatically after the `task` closure returns. On success, the value returned from closure will be the wrapped as `.success(userInfo: T)` in the `completion`'s `Result<T>`. Any errors thrown from inside the `task` will be reported as `.failure(error: CoreStoreError)`. To cancel/rollback changes, call `try transaction.cancel()`, which throws a `CoreStoreError.userCancelled`.
      
      - parameter task: the asynchronous closure where creates, updates, and deletes can be made to the transaction. Transaction blocks are executed serially in a background queue, and all changes are made from a concurrent `NSManagedObjectContext`.
-     - parameter completion: the closure executed after the save completes. The `TransactionResult` argument of the closure will either wrap the return value of `task`, or any uncaught errors thrown from within `task`. Cancelled `task`s will be indicated by `CoreStoreError.userCancelled`. Custom errors thrown by the user will be wrapped in `CoreStoreError.userError(error: Error)`.
+     - parameter completion: the closure executed after the save completes. The `Result` argument of the closure will either wrap the return value of `task`, or any uncaught errors thrown from within `task`. Cancelled `task`s will be indicated by `.failure(error: CoreStoreError.userCancelled)`. Custom errors thrown by the user will be wrapped in `CoreStoreError.userError(error: Error)`.
      */
     public func perform<T>(asynchronous task: @escaping (_ transaction: AsynchronousDataTransaction) throws -> T, completion: @escaping (AsynchronousDataTransaction.Result<T>) -> Void) {
         
@@ -47,11 +47,11 @@ public extension DataStack {
     }
     
     /**
-     Performs a transaction asynchronously where `NSManagedObject` creates, updates, and deletes can be made. The changes are commited automatically after the `task` closure returns. On success, the value returned from closure will be the argument of the `success` closure. Any errors thrown from inside the `task` will be wrapped in a `CoreStoreError` and reported in the `failure` closure. To cancel/rollback changes, call `transaction.cancel()`, which throws a `CoreStoreError.userCancelled`.
+     Performs a transaction asynchronously where `NSManagedObject` or `CoreStoreObject` creates, updates, and deletes can be made. The changes are commited automatically after the `task` closure returns. On success, the value returned from closure will be the argument of the `success` closure. Any errors thrown from inside the `task` will be wrapped in a `CoreStoreError` and reported in the `failure` closure. To cancel/rollback changes, call `try transaction.cancel()`, which throws a `CoreStoreError.userCancelled`.
      
      - parameter task: the asynchronous closure where creates, updates, and deletes can be made to the transaction. Transaction blocks are executed serially in a background queue, and all changes are made from a concurrent `NSManagedObjectContext`.
      - parameter success: the closure executed after the save succeeds. The `T` argument of the closure will be the value returned from `task`.
-     - parameter failure: the closure executed if the save fails or if any errors are thrown within `task`.  Cancelled `task`s will be indicated by `CoreStoreError.userCancelled`. Custom errors thrown by the user will be wrapped in `CoreStoreError.userError(error: Error)`.
+     - parameter failure: the closure executed if the save fails or if any errors are thrown within `task`. Cancelled `task`s will be indicated by `CoreStoreError.userCancelled`. Custom errors thrown by the user will be wrapped in `CoreStoreError.userError(error: Error)`.
      */
     public func perform<T>(asynchronous task: @escaping (_ transaction: AsynchronousDataTransaction) throws -> T, success: @escaping (T) -> Void, failure: @escaping (CoreStoreError) -> Void) {
         
@@ -61,6 +61,10 @@ public extension DataStack {
         )
         transaction.transactionQueue.cs_async {
             
+            defer {
+                
+                withExtendedLifetime(transaction, {})
+            }
             let userInfo: T
             do {
                 
@@ -91,7 +95,7 @@ public extension DataStack {
     }
     
     /**
-     Performs a transaction synchronously where `NSManagedObject` creates, updates, and deletes can be made. The changes are commited automatically after the `task` closure returns. On success, the value returned from closure will be the return value of `perform(synchronous:)`. Any errors thrown from inside the `task` will be rethrown from `perform(synchronous:)`. To cancel/rollback changes, call `transaction.cancel()`, which throws a `CoreStoreError.userCancelled`.
+     Performs a transaction synchronously where `NSManagedObject` or `CoreStoreObject` creates, updates, and deletes can be made. The changes are commited automatically after the `task` closure returns. On success, the value returned from closure will be the return value of `perform(synchronous:)`. Any errors thrown from inside the `task` will be rethrown from `perform(synchronous:)`. To cancel/rollback changes, call `try transaction.cancel()`, which throws a `CoreStoreError.userCancelled`.
      
      - parameter task: the synchronous non-escaping closure where creates, updates, and deletes can be made to the transaction. Transaction blocks are executed serially in a background queue, and all changes are made from a concurrent `NSManagedObjectContext`.
      - parameter waitForAllObservers: When `true`, this method waits for all observers to be notified of the changes before returning. This results in more predictable data update order, but may risk triggering deadlocks. When `false`, this method does not wait for observers to be notified of the changes before returning. This results in lower risk for deadlocks, but the updated data may not have been propagated to the `DataStack` after returning. Defaults to `true`.
@@ -106,6 +110,10 @@ public extension DataStack {
         )
         return try transaction.transactionQueue.cs_sync {
             
+            defer {
+                
+                withExtendedLifetime(transaction, {})
+            }
             let userInfo: T
             do {
                 
@@ -131,7 +139,7 @@ public extension DataStack {
     }
     
     /**
-     Begins a non-contiguous transaction where `NSManagedObject` creates, updates, and deletes can be made. This is useful for making temporary changes, such as partially filled forms.
+     Begins a non-contiguous transaction where `NSManagedObject` or `CoreStoreObject` creates, updates, and deletes can be made. This is useful for making temporary changes, such as partially filled forms.
      
      - prameter supportsUndo: `undo()`, `redo()`, and `rollback()` methods are only available when this parameter is `true`, otherwise those method will raise an exception. Defaults to `false`. Note that turning on Undo support may heavily impact performance especially on iOS or watchOS where memory is limited.
      - returns: a `UnsafeDataTransaction` instance where creates, updates, and deletes can be made.
@@ -146,7 +154,7 @@ public extension DataStack {
     }
     
     /**
-     Refreshes all registered objects `NSManagedObject`s in the `DataStack`.
+     Refreshes all registered objects `NSManagedObject`s or `CoreStoreObject`s in the `DataStack`.
      */
     public func refreshAndMergeAllObjects() {
         
@@ -160,11 +168,6 @@ public extension DataStack {
     
     // MARK: Deprecated
     
-    /**
-     Begins a transaction asynchronously where `NSManagedObject` creates, updates, and deletes can be made.
-     
-     - parameter closure: the block where creates, updates, and deletes can be made to the transaction. Transaction blocks are executed serially in a background queue, and all changes are made from a concurrent `NSManagedObjectContext`.
-     */
     @available(*, deprecated, message: "Use the new auto-commiting methods `perform(asynchronous:completion:)` or `perform(asynchronous:success:failure:)`. Please read the documentation on the behavior of the new methods.")
     public func beginAsynchronous(_ closure: @escaping (_ transaction: AsynchronousDataTransaction) -> Void) {
         
@@ -186,12 +189,6 @@ public extension DataStack {
         }
     }
     
-    /**
-     Begins a transaction synchronously where `NSManagedObject` creates, updates, and deletes can be made.
-     
-     - parameter closure: the block where creates, updates, and deletes can be made to the transaction. Transaction blocks are executed serially in a background queue, and all changes are made from a concurrent `NSManagedObjectContext`.
-     - returns: a `SaveResult` value indicating success or failure, or `nil` if the transaction was not comitted synchronously
-     */
     @available(*, deprecated, message: "Use the new auto-commiting method `perform(synchronous:)`. Please read the documentation on the behavior of the new methods.")
     @discardableResult
     public func beginSynchronous(_ closure: @escaping (_ transaction: SynchronousDataTransaction) -> Void) -> SaveResult? {