insidegui · July 6, 2022 20:00 · Jul 6, 2022
diff --git a/Animation+Slow.swift b/Animation+Slow.swift
@@ -0,0 +1,31 @@
+import SwiftUI
+
+/// On macOS, modifying an Animation with .currentSpeed(), or using the .current static property
+/// allows for easy animation debugging by holding down the Shift key when triggering the animation.
+/// When the animation is triggered while the Shift key is pressed, it will be played in slow motion.
+/// Using this extension has no effect when targeting other OSes or when building for release.
+extension Animation {
+
+    static var currentSpeed: Double {
+        #if DEBUG
+        #if os(macOS)
+        if NSEvent.modifierFlags.contains(.shift) {
+            return 0.1
+        } else {
+            return 1
+        }
+        #else
+        return 1
+        #endif
+        #else
+        return 1
+        #endif
+    }
+
+    static var current: Animation { Animation.default.currentSpeed() }
+
+    func currentSpeed() -> Animation {
+        speed(Self.currentSpeed)
+    }
+
+}