From 70a210b27615f52eccfd4b80fe02f7d656bedeb0 Mon Sep 17 00:00:00 2001
From: Christian Treffs <ctreffs@gmail.com>
Date: Thu, 23 Jul 2020 22:04:17 +0200
Subject: [PATCH] Return newly created entities

---
 Sources/FirebladeECS/Family+Coding.swift       |  9 +++++----
 .../FirebladeECSTests/FamilyCodingTests.swift  | 18 ++++++++++++------
 2 files changed, 17 insertions(+), 10 deletions(-)

diff --git a/Sources/FirebladeECS/Family+Coding.swift b/Sources/FirebladeECS/Family+Coding.swift
index 2cb764f..692758f 100644
--- a/Sources/FirebladeECS/Family+Coding.swift
+++ b/Sources/FirebladeECS/Family+Coding.swift
@@ -76,11 +76,12 @@ extension Family where R: FamilyDecoding {
     /// - Parameters:
     ///   - data: The data decoded by decoder. A unkeyed container of family members (keyed component containers) is expected.
     ///   - decoder: The decoder to use for decoding family member data. Decoder respects the coding strategy set at `nexus.codingStrategy`.
-    public func decodeMembers<Decoder>(from data: Decoder.Input, using decoder: inout Decoder) throws where Decoder: TopLevelDecoder {
+    /// - Returns: returns the newly added entities.
+    @discardableResult
+    public func decodeMembers<Decoder>(from data: Decoder.Input, using decoder: inout Decoder) throws -> [Entity] where Decoder: TopLevelDecoder {
         decoder.userInfo[.nexusCodingStrategy] = nexus.codingStrategy
         let familyMembers = try decoder.decode(FamilyMemberContainer<R>.self, from: data)
-        for components in familyMembers.components {
-            createMember(with: components)
-        }
+        return familyMembers.components
+            .map { createMember(with: $0) }
     }
 }
diff --git a/Tests/FirebladeECSTests/FamilyCodingTests.swift b/Tests/FirebladeECSTests/FamilyCodingTests.swift
index 0de9117..8da696f 100644
--- a/Tests/FirebladeECSTests/FamilyCodingTests.swift
+++ b/Tests/FirebladeECSTests/FamilyCodingTests.swift
@@ -46,8 +46,8 @@ final class FamilyCodingTests: XCTestCase {
         let family = nexus.family(requires: MyComponent.self)
         XCTAssertTrue(family.isEmpty)
         var jsonDecoder = JSONDecoder()
-        try family.decodeMembers(from: jsonData, using: &jsonDecoder)
-
+        let newEntities = try family.decodeMembers(from: jsonData, using: &jsonDecoder)
+        XCTAssertEqual(newEntities.count, 2)
         XCTAssertEqual(family.count, 2)
 
     }
@@ -96,7 +96,8 @@ final class FamilyCodingTests: XCTestCase {
         let family = nexus.family(requiresAll: YourComponent.self, MyComponent.self)
         XCTAssertTrue(family.isEmpty)
         var jsonDecoder = JSONDecoder()
-        try family.decodeMembers(from: jsonData, using: &jsonDecoder)
+        let newEntities = try family.decodeMembers(from: jsonData, using: &jsonDecoder)
+        XCTAssertEqual(newEntities.count, 2)
         XCTAssertEqual(family.count, 2)
     }
 
@@ -150,10 +151,13 @@ final class FamilyCodingTests: XCTestCase {
         let nexus = Nexus()
 
         let family = nexus.family(requiresAll: YourComponent.self, MyComponent.self, Position.self)
+        let family2 = nexus.family(requiresAll: YourComponent.self, MyComponent.self, excludesAll: Index.self)
         XCTAssertTrue(family.isEmpty)
         var jsonDecoder = JSONDecoder()
-        try family.decodeMembers(from: jsonData, using: &jsonDecoder)
+        let newEntities = try family.decodeMembers(from: jsonData, using: &jsonDecoder)
+        XCTAssertEqual(newEntities.count, 2)
         XCTAssertEqual(family.count, 2)
+        XCTAssertEqual(family2.count, 2)
     }
 
     func testEncodeFamily4() throws {
@@ -218,7 +222,8 @@ final class FamilyCodingTests: XCTestCase {
         let family = nexus.family(requiresAll: YourComponent.self, MyComponent.self, Position.self, Color.self)
         XCTAssertTrue(family.isEmpty)
         var jsonDecoder = JSONDecoder()
-        try family.decodeMembers(from: jsonData, using: &jsonDecoder)
+        let newEntities = try family.decodeMembers(from: jsonData, using: &jsonDecoder)
+        XCTAssertEqual(newEntities.count, 2)
         XCTAssertEqual(family.count, 2)
     }
 
@@ -290,7 +295,8 @@ final class FamilyCodingTests: XCTestCase {
         let family = nexus.family(requiresAll: YourComponent.self, MyComponent.self, Position.self, Color.self, Party.self)
         XCTAssertTrue(family.isEmpty)
         var jsonDecoder = JSONDecoder()
-        try family.decodeMembers(from: jsonData, using: &jsonDecoder)
+        let newEntities = try family.decodeMembers(from: jsonData, using: &jsonDecoder)
+        XCTAssertEqual(newEntities.count, 2)
         XCTAssertEqual(family.count, 2)
     }