add insertItems:toIndexPaths method, add totalNumberOfItems computed …

…property

CHANGELOG.md

@@ -1,9 +1,19 @@
 # Change Log
 All notable changes to this project will be documented in this file.
 
-## Master
+## [2.5.0](https://github.com/DenHeadless/DTModelStorage/releases/tag/2.5.0)
+
+## Breaking
 
 * Update to Swift 2.2. This release is not backwards compatible with Swift 2.1.
+
+## Added
+
+* `insertItems(_:toIndexPaths:)` method, that mirrors UITableView `insertRowsAtIndexPaths(_:withRowAnimation:)` and UICollectionView `insertItemsAtIndexPaths(_:)` method
+* `totalNumberOfItems` computed property in `MemoryStorage`, that allows getting current total number of items across all storage.
+
+## Changed
+
 * Require Only-App-Extension-Safe API is set to YES in framework targets.
 
 ## [2.4.4](https://github.com/DenHeadless/DTModelStorage/releases/tag/2.4.4)

DTModelStorage.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name     = 'DTModelStorage'
-  s.version  = '2.4.4'
+  s.version  = '2.5.0'
   s.license  = 'MIT'
   s.summary  = 'Storage classes for datasource based controls.'
   s.homepage = 'https://github.com/DenHeadless/DTModelStorage'

DTModelStorage/Sources/Core/MemoryStorage.swift

@@ -28,19 +28,26 @@ import Foundation
 /// This struct contains error types that can be thrown for various MemoryStorage errors
 public struct MemoryStorageErrors
 {
-    /// Errors that can happen when inserting items into memory storage
+    /// Errors that can happen when inserting items into memory storage - `insertItem(_:toIndexPath:)` method
     public enum Insertion: ErrorType
     {
         case IndexPathTooBig
     }
 
-    /// Errors that can happen when replacing item in memory storage
+    /// Errors that can be thrown, when calling `insertItems(_:toIndexPaths:)` method
+    public enum BatchInsertion: ErrorType
+    {
+        /// Is thrown, if length of batch inserted array is different from length of array of index paths.
+        case ItemsCountMismatch
+    }
+
+    /// Errors that can happen when replacing item in memory storage - `replaceItem(_:replacingItem:)` method
     public enum Replacement: ErrorType
     {
         case ItemNotFound
     }
 
-    /// Errors that can happen when removing item from memory storage
+    /// Errors that can happen when removing item from memory storage - `removeItem(:_)` method
     public enum Removal : ErrorType
     {
         case ItemNotFound
@@ -57,6 +64,13 @@ public class MemoryStorage: BaseStorage, StorageProtocol, SupplementaryStoragePr
     /// sections of MemoryStorage
     public var sections: [Section] = [SectionModel]()
 
+    /// Returns total number of items contained in all `MemoryStorage` sections
+    public var totalNumberOfItems : Int {
+        return sections.reduce(0) { sum, section in
+            return sum + section.numberOfItems
+        }
+    }
+
     /// Retrieve item at index path from `MemoryStorage`
     /// - Parameter path: NSIndexPath for item
     /// - Returns: model at indexPath or nil, if item not found
@@ -221,6 +235,27 @@ public class MemoryStorage: BaseStorage, StorageProtocol, SupplementaryStoragePr
         self.finishUpdate()
     }
 
+    /// Insert item to indexPaths
+    /// - Parameter items: items to insert
+    /// - Parameter toIndexPaths: indexPaths to insert
+    /// - Throws: if items.count is different from indexPaths.count, will throw MemoryStorageErrors.BatchInsertion.ItemsCountMismatch
+    public func insertItems<T>(items: [T], toIndexPaths indexPaths: [NSIndexPath]) throws
+    {
+        if items.count != indexPaths.count {
+            throw MemoryStorageErrors.BatchInsertion.ItemsCountMismatch
+        }
+        performUpdates {
+            indexPaths.enumerate().forEach { itemIndex, indexPath in
+                let section = getValidSection(indexPath.section)
+                guard section.items.count >= indexPath.item else {
+                    return
+                }
+                section.items.insert(items[itemIndex], atIndex: indexPath.item)
+                currentUpdate?.insertedRowIndexPaths.insert(indexPath)
+            }
+        }
+    }
+
     /// Reload item
     /// - Parameter item: item to reload.
     public func reloadItem<T:Equatable>(item: T)

DTModelStorageTests/XCTests/Specs/MemoryStorage/MemoryStorageEditSpecs.swift

@@ -447,4 +447,31 @@ class SectionSupplementariesTestCase : XCTestCase
 
         expect(self.storage.sectionAtIndex(1)?.itemsOfType(Int)) == [7,8,9]
     }
+
+    func testInsertItemsAtIndexPathsSuccessfullyInsertsItems() {
+        try! storage.insertItems([1,2,3], toIndexPaths: [indexPath(0, 0), indexPath(1, 0), indexPath(2, 0)])
+
+        expect(self.storage.itemsInSection(0)?.count) == 3
+        expect(self.storage.sectionAtIndex(0)?.itemsOfType(Int)) == [1,2,3]
+    }
+
+    func testWrongCountsRaisesException() {
+        do {
+            try storage.insertItems([1,2], toIndexPaths: [indexPath(0, 0)])
+        }
+        catch MemoryStorageErrors.BatchInsertion.ItemsCountMismatch {
+            return
+        }
+        catch {
+            XCTFail()
+        }
+        XCTFail()
+    }
+
+    func testInsertItemsAtIndexPathsDoesNotTryToInsertItemsPastItemsCount() {
+        try! storage.insertItems([1,2,3], toIndexPaths: [indexPath(0, 0), indexPath(1, 0),indexPath(3, 0)])
+
+        expect(self.storage.itemsInSection(0)?.count) == 2
+        expect(self.storage.sectionAtIndex(0)?.itemsOfType(Int)) == [1,2]
+    }
 }