From 4afb1cfc4d52a49e8e09ded64b08aea066f7247a Mon Sep 17 00:00:00 2001
From: Jackson Cheek <jackson.cheek@gmail.com>
Date: Thu, 21 Sep 2023 14:19:34 -0400
Subject: [PATCH] Update concatenation logic and unit tests

---
 .../Sources/Layout/LayoutAttributes.swift     | 18 ++++++++-----
 .../Sources/Layout/LayoutSubelement.swift     |  2 +-
 BlueprintUI/Tests/LayoutAttributesTests.swift | 27 ++++++++++++++-----
 3 files changed, 33 insertions(+), 14 deletions(-)

diff --git a/BlueprintUI/Sources/Layout/LayoutAttributes.swift b/BlueprintUI/Sources/Layout/LayoutAttributes.swift
index eac5d6496..18d7c8fff 100755
--- a/BlueprintUI/Sources/Layout/LayoutAttributes.swift
+++ b/BlueprintUI/Sources/Layout/LayoutAttributes.swift
@@ -30,7 +30,7 @@ public struct LayoutAttributes {
     public var isHidden: Bool
 
     /// Corresponds to `UIView.tintAdjustmentMode`.
-    public var tintAdjustmentMode: UIView.TintAdjustmentMode?
+    public var tintAdjustmentMode: UIView.TintAdjustmentMode
 
     public init() {
         self.init(center: .zero, bounds: .zero)
@@ -54,7 +54,7 @@ public struct LayoutAttributes {
         alpha = 1.0
         isUserInteractionEnabled = true
         isHidden = false
-        tintAdjustmentMode = nil
+        tintAdjustmentMode = .automatic
 
         validateBounds()
         validateCenter()
@@ -93,9 +93,7 @@ public struct LayoutAttributes {
         view.alpha = alpha
         view.isUserInteractionEnabled = isUserInteractionEnabled
         view.isHidden = isHidden
-        if let tintAdjustmentMode {
-            view.tintAdjustmentMode = tintAdjustmentMode
-        }
+        view.tintAdjustmentMode = tintAdjustmentMode
     }
 
 
@@ -163,7 +161,15 @@ public struct LayoutAttributes {
         result.alpha = alpha * layoutAttributes.alpha
         result.isUserInteractionEnabled = layoutAttributes.isUserInteractionEnabled && isUserInteractionEnabled
         result.isHidden = layoutAttributes.isHidden || isHidden
-        result.tintAdjustmentMode = layoutAttributes.tintAdjustmentMode ?? tintAdjustmentMode
+
+        switch tintAdjustmentMode {
+        case .dimmed, .normal:
+            result.tintAdjustmentMode = tintAdjustmentMode
+        case .automatic:
+            result.tintAdjustmentMode = layoutAttributes.tintAdjustmentMode
+        @unknown default:
+            result.tintAdjustmentMode = layoutAttributes.tintAdjustmentMode
+        }
 
         return result
     }
diff --git a/BlueprintUI/Sources/Layout/LayoutSubelement.swift b/BlueprintUI/Sources/Layout/LayoutSubelement.swift
index 3e03721f5..fa8b0c9cd 100644
--- a/BlueprintUI/Sources/Layout/LayoutSubelement.swift
+++ b/BlueprintUI/Sources/Layout/LayoutSubelement.swift
@@ -182,7 +182,7 @@ extension LayoutSubelement {
         public var isHidden: Bool = false
 
         /// Corresponds to `UIView.tintAdjustmentMode`.
-        public var tintAdjustmentMode: UIView.TintAdjustmentMode?
+        public var tintAdjustmentMode: UIView.TintAdjustmentMode = .automatic
     }
 
     @propertyWrapper
diff --git a/BlueprintUI/Tests/LayoutAttributesTests.swift b/BlueprintUI/Tests/LayoutAttributesTests.swift
index f73d7078f..9388dbeb3 100644
--- a/BlueprintUI/Tests/LayoutAttributesTests.swift
+++ b/BlueprintUI/Tests/LayoutAttributesTests.swift
@@ -189,9 +189,9 @@ final class LayoutAttributesTests: XCTestCase {
 
     func test_concat_tintAdjustmentMode() {
         do {
-            /// parent adopts child attribute if parent not set
+            /// combined adopts child attribute if child is non-`.automatic`
             var a = LayoutAttributes()
-            a.tintAdjustmentMode = nil
+            a.tintAdjustmentMode = .automatic
 
             var b = LayoutAttributes()
             b.tintAdjustmentMode = .normal
@@ -202,12 +202,12 @@ final class LayoutAttributesTests: XCTestCase {
         }
 
         do {
-            /// parent overrides child
+            /// combined adopts child attribute if both child and parent are non-`.automatic`
             var a = LayoutAttributes()
-            a.tintAdjustmentMode = .normal
+            a.tintAdjustmentMode = .dimmed
 
             var b = LayoutAttributes()
-            b.tintAdjustmentMode = .dimmed
+            b.tintAdjustmentMode = .normal
 
             let combined = b.within(a)
 
@@ -215,17 +215,30 @@ final class LayoutAttributesTests: XCTestCase {
         }
 
         do {
-            /// child inherits from parent
+            /// combined inherits from parent if child is `.automatic`
             var a = LayoutAttributes()
             a.tintAdjustmentMode = .normal
 
             var b = LayoutAttributes()
-            b.tintAdjustmentMode = nil
+            b.tintAdjustmentMode = .automatic
 
             let combined = b.within(a)
 
             XCTAssertEqual(combined.tintAdjustmentMode, .normal)
         }
+
+        do {
+            /// combined is `.automatic` if both parent and child attributes are `.automatic`
+            var a = LayoutAttributes()
+            a.tintAdjustmentMode = .automatic
+
+            var b = LayoutAttributes()
+            b.tintAdjustmentMode = .automatic
+
+            let combined = b.within(a)
+
+            XCTAssertEqual(combined.tintAdjustmentMode, .automatic)
+        }
     }
 }