Revise addItem and addItems methods

Sources/Layout/Layout.swift

@@ -108,39 +108,28 @@ public final class Layout { // swiftlint:disable:this type_body_length
 
     // MARK: - Adding Items
 
-    /// Adds items to the layout.
+    /// Adds an item to the layout.
     ///
-    /// - Parameter items: The items to be added as subviews.
+    /// - Parameter item: The item to be added as a subview.
     ///
-    /// - Returns: The receiver with the added subviews.
+    /// - Returns: The receiver with the added subview.
     @discardableResult
-    public func addItems(
-        _ items: LayoutItem...
+    public func addItem(
+        _ item: LayoutItem
     ) -> Layout {
-        addItems(items)
+        addItems([item])
     }
 
     /// Adds items to the layout.
     ///
-    /// - Parameter items: The items to be added as subviews.
+    /// - Parameter items: The builder that creates the items to be added as subviews.
     ///
     /// - Returns: The receiver with the added subviews.
     @discardableResult
     public func addItems(
-        _ items: [LayoutItem]
+        @LayoutBuilder items: () -> [LayoutItem]
     ) -> Layout {
-        items.forEach { item in
-            let subview: UIView = item.layoutItemView
-            subview.translatesAutoresizingMaskIntoConstraints = false
-            if subview.superview != view {
-                view?.addSubview(subview)
-            }
-            if let key: String = subview.identifier, !key.isEmpty {
-                self.items[key] = subview
-            }
-            adding(item.superviewConstraints(item))
-        }
-        return self
+        addItems(items())
     }
 
     // MARK: - Adding Constraints
@@ -744,4 +733,24 @@ public final class Layout { // swiftlint:disable:this type_body_length
         view.setNeedsUpdateConstraints()
         view.updateConstraintsIfNeeded()
     }
+
+    // MARK: - Private
+
+    @discardableResult
+    private func addItems(
+        _ items: [LayoutItem]
+    ) -> Layout {
+        items.forEach { item in
+            let subview: UIView = item.layoutItemView
+            subview.translatesAutoresizingMaskIntoConstraints = false
+            if subview.superview != view {
+                view?.addSubview(subview)
+            }
+            if let key: String = subview.identifier, !key.isEmpty {
+                self.items[key] = subview
+            }
+            adding(item.superviewConstraints(item))
+        }
+        return self
+    }
 }

Sources/Layout/LayoutItem.swift

@@ -30,7 +30,7 @@ public typealias SuperviewConstraints = (LayoutItem) -> [NSLayoutConstraint]
  * // Creating a layout with multiple items
  * let item1: LayoutItem = subview1.toEdges()
  * let item2: LayoutItem = subview2.square().center()
- * view.layout().addItems(item1, item2).activate()
+ * view.layout(item1).addItem(item2).activate()
  * ```
  *
  * The following code demonstrates the preferred way of constructing and activating a layout with multiple items

Tests/LayoutTests/LayoutExampleTests.swift

@@ -197,7 +197,7 @@ final class LayoutExampleTests: XCTestCase {
         assertLayout { view in
             let item1: LayoutItem = subview1.toEdges()
             let item2: LayoutItem = subview2.square().center()
-            view.layout().addItems(item1, item2).activate()
+            view.layout(item1).addItem(item2).activate()
         }
     }
 

Tests/LayoutTests/LayoutTests.swift

@@ -147,28 +147,26 @@ final class LayoutTests: XCTestCase {
 
     // MARK: - Adding Items
 
-    func testAddItemsVariadic() {
+    func testAddItem() {
 
         // GIVEN
 
         let view: UIView = .init()
         let layout: Layout = .init(view)
-        let view1: UIView = .init()
-        let view2: UIView = .init()
+        let subview: UIView = .init()
 
         // THEN
 
         expect(layout.items.isEmpty) == true
 
         // WHEN
 
-        layout.addItems(view1.id("view1"), view2.id("view2"))
+        layout.addItem(subview.id("subview"))
 
         // THEN
 
-        expect(layout.items.count) == 2
-        expect(layout.items["view1"]) === view1
-        expect(layout.items["view2"]) === view2
+        expect(layout.items.count) == 1
+        expect(layout.items["subview"]) === subview
     }
 
     func testAddItems() {
@@ -177,22 +175,25 @@ final class LayoutTests: XCTestCase {
 
         let view: UIView = .init()
         let layout: Layout = .init(view)
-        let view1: UIView = .init()
-        let view2: UIView = .init()
+        let subview1: UIView = .init()
+        let subview2: UIView = .init()
 
         // THEN
 
         expect(layout.items.isEmpty) == true
 
         // WHEN
 
-        layout.addItems([view1.id("view1"), view2.id("view2")])
+        layout.addItems {
+            subview1.id("subview1")
+            subview2.id("subview2")
+        }
 
         // THEN
 
         expect(layout.items.count) == 2
-        expect(layout.items["view1"]) === view1
-        expect(layout.items["view2"]) === view2
+        expect(layout.items["subview1"]) === subview1
+        expect(layout.items["subview2"]) === subview2
     }
 
     // MARK: - Adding Constraints
@@ -670,7 +671,7 @@ final class LayoutTests: XCTestCase {
         let superview: UIView = .init()
         let view1: UIView = .init()
         let view2: UIView = .init()
-        let layout: Layout = superview.layout().addItems(view1, view2)
+        let layout: Layout = superview.layout(view1).addItem(view2)
 
         // WHEN
 
@@ -762,7 +763,7 @@ final class LayoutTests: XCTestCase {
         var superview: UIView? = .init()
         let view: UIView = .init()
         let siblingView: UIView = .init()
-        let layout: Layout = superview!.layout().addItems(view, siblingView)
+        let layout: Layout = superview!.layout(view).addItem(siblingView)
         let leadingAnchor: NSLayoutXAxisAnchor = siblingView.trailing
         let trailingAnchor: NSLayoutXAxisAnchor = superview!.trailing
 
@@ -822,7 +823,7 @@ final class LayoutTests: XCTestCase {
         var superview: UIView? = .init()
         let view: UIView = .init()
         let siblingView: UIView = .init()
-        let layout: Layout = superview!.layout().addItems(view, siblingView)
+        let layout: Layout = superview!.layout(view).addItem(siblingView)
         let topAnchor: NSLayoutYAxisAnchor = siblingView.bottom
         let bottomAnchor: NSLayoutYAxisAnchor = superview!.bottom
 
@@ -941,7 +942,7 @@ final class LayoutTests: XCTestCase {
         let superview: UIView = .init()
         let view1: UIView = .init()
         let view2: UIView = .init()
-        let layout: Layout = superview.layout().addItems(view1, view2)
+        let layout: Layout = superview.layout(view1).addItem(view2)
 
         // WHEN
 
@@ -1043,7 +1044,7 @@ final class LayoutTests: XCTestCase {
         let superview: UIView = .init()
         let view1: UIView = .init()
         let view2: UIView = .init()
-        let layout: Layout = superview.layout().addItems(view1, view2)
+        let layout: Layout = superview.layout(view1).addItem(view2)
 
         // WHEN
 
@@ -1084,7 +1085,7 @@ final class LayoutTests: XCTestCase {
         // WHEN
 
         layout
-            .addItems(subview.id("subview"))
+            .addItem(subview.id("subview"))
             .horizontal(format)
 
         // THEN
@@ -1118,9 +1119,11 @@ final class LayoutTests: XCTestCase {
 
         // WHEN
 
-        layout
-            .addItems(subview1.id("subview1"), subview2.id("subview2"))
-            .horizontal(format, metrics: metrics, options: .alignAllCenterY)
+        layout.addItems {
+            subview1.id("subview1")
+            subview2.id("subview2")
+        }
+        .horizontal(format, metrics: metrics, options: .alignAllCenterY)
 
         // THEN
 
@@ -1148,7 +1151,7 @@ final class LayoutTests: XCTestCase {
         // WHEN
 
         layout
-            .addItems(subview.id("subview"))
+            .addItem(subview.id("subview"))
             .vertical(format)
 
         // THEN
@@ -1182,9 +1185,11 @@ final class LayoutTests: XCTestCase {
 
         // WHEN
 
-        layout
-            .addItems(subview1.id("subview1"), subview2.id("subview2"))
-            .vertical(format, metrics: metrics, options: .alignAllCenterX)
+        layout.addItems {
+            subview1.id("subview1")
+            subview2.id("subview2")
+        }
+        .vertical(format, metrics: metrics, options: .alignAllCenterX)
 
         // THEN