Adding aspect ratio functions

Sources/Stevia/Stevia+Percentage.swift

@@ -27,6 +27,28 @@ public postfix func % (v: Int) -> SteviaPercentage {
 }
 
 public extension UIView {
+
+    /**
+     Adds an Autolayout constraint to provide the aspect ratio for the view.
+
+     ```
+     image.aspectRatio(3/2)
+     image.aspectRatio(150%)
+
+     // is equivalent to
+
+     image.Width == image.Height * 1.5
+     image.Width == 150 % image.Height
+     ```
+
+     - Returns: Itself, enabling chaining,
+
+     */
+    @discardableResult
+    func aspectRatio(_ p: SteviaPercentage) -> Self {
+        Width == p.value % Height
+        return self
+    }
 
     /**
      Adds an Autolayout constraint for sizing the view.

Sources/Stevia/Stevia+Size.swift

@@ -10,7 +10,73 @@
 import UIKit
 
 public extension UIView {
-
+
+    /**
+     Adds an Autolayout constraint to provide the aspect ratio for the view.
+
+     ```
+     image.aspectRatio(3.0/2.0)
+     image.aspectRatio(150%)
+
+     // is equivalent to
+
+     image.Width == image.Height * 1.5
+     image.Width == 150 % image.Height
+     ```
+
+     - Returns: Itself, enabling chaining,
+
+     */
+    @discardableResult
+    func aspectRatio(_ ratio: Double = 1) -> Self {
+        Width == Height * ratio
+        return self
+    }
+
+    /**
+     Adds an Autolayout constraint to provide the aspect ratio for the view.
+
+     ```
+     image.aspectRatio(3.0/2.0)
+     image.aspectRatio(150%)
+
+     // is equivalent to
+
+     image.Width == image.Height * 1.5
+     image.Width == 150 % image.Height
+     ```
+
+     - Returns: Itself, enabling chaining,
+
+     */
+    @discardableResult
+    func aspectRatio(_ ratio: CGFloat = 1) -> Self {
+        aspectRatio(Double(ratio))
+        return self
+    }
+
+    /**
+     Adds an Autolayout constraint to provide the aspect ratio for the view.
+
+     ```
+     image.aspectRatio(3.0/2.0)
+     image.aspectRatio(150%)
+
+     // is equivalent to
+
+     image.Width == image.Height * 1.5
+     image.Width == 150 % image.Height
+     ```
+
+     - Returns: Itself, enabling chaining,
+
+     */
+    @discardableResult
+    func aspectRatio(_ ratio: Int = 1) -> Self {
+        aspectRatio(Double(ratio))
+        return self
+    }
+
     /**
      Adds an Autolayout constraint for sizing the view.
 

Tests/SteviaTests/SizeTests.swift

@@ -24,6 +24,46 @@ import Stevia
         }
     }
 
+    @Test
+    func testAspectRatioDouble() {
+        v.width(150).aspectRatio(Double(3.0/2.0))
+        ctrler.view.layoutIfNeeded()
+        #expect(v.frame.origin.y == 0)
+        #expect(v.frame.origin.x == 0)
+        #expect(v.frame.width == 150)
+        #expect(v.frame.height == 100)
+    }
+
+    @Test
+    func testAspectRatioCGFloat() {
+        v.width(150).aspectRatio(CGFloat(3.0/2.0))
+        ctrler.view.layoutIfNeeded()
+        #expect(v.frame.origin.y == 0)
+        #expect(v.frame.origin.x == 0)
+        #expect(v.frame.width == 150)
+        #expect(v.frame.height == 100)
+    }
+
+    @Test
+    func testAspectRatioInt() {
+        v.width(150).aspectRatio(Int(3))
+        ctrler.view.layoutIfNeeded()
+        #expect(v.frame.origin.y == 0)
+        #expect(v.frame.origin.x == 0)
+        #expect(v.frame.width == 150)
+        #expect(v.frame.height == 50)
+    }
+
+    @Test
+    func testAspectRatioPercentage() {
+        v.width(150).aspectRatio(150%)
+        ctrler.view.layoutIfNeeded()
+        #expect(v.frame.origin.y == 0)
+        #expect(v.frame.origin.x == 0)
+        #expect(v.frame.width == 150)
+        #expect(v.frame.height == 100)
+    }
+
     @Test
     func testSizeDouble() {
         v.size(Double(57))