Test UIView.sizeToFit(constrainedSize)

Also changed how it works, and the arguments it can take. All for the
better.

Author: Baris Sencan

ManualLayout/UIView+ManualLayout.swift

@@ -101,13 +101,15 @@ public extension UIView {
 
   // MARK: - Automatic Sizing
 
-  public func sizeToFit(constrainedSizeTuple: (CGFloat, CGFloat)) {
-    sizeToFit(CGSize(
-      width: constrainedSizeTuple.0,
-      height: constrainedSizeTuple.1))
+  public func sizeToFit(width: CGFloat, _ height: CGFloat) -> CGSize {
+    return sizeToFit(CGSize(width: width, height: height))
   }
 
-  public func sizeToFit(constrainedSize: CGSize) {
-    size = sizeThatFits(constrainedSize)
+  public func sizeToFit(constrainedSize: CGSize) -> CGSize {
+    var newSize = sizeThatFits(constrainedSize)
+    newSize.width = min(newSize.width, constrainedSize.width)
+    newSize.height = min(newSize.height, constrainedSize.height)
+    size = newSize
+    return newSize
   }
-}
+}

ManualLayoutTests/UIViewManualLayoutTests.swift

@@ -226,4 +226,21 @@ class UIViewManualLayoutTests: XCTestCase {
       "left2 changes without a swap should modify frame size")
     // TODO: Test swap behavior.
   }
-}
+
+  func testSizeToFit() {
+    let containerView = UIView(frame: CGRect(x: 0, y: 0, width: 20, height: 200))
+    let label = UILabel(frame: CGRectZero)
+    label.text = "lorem ipsum dolor sit amet"
+    label.numberOfLines = 5
+    containerView.addSubview(label)
+    label.sizeToFit(containerView.frame.size)
+    XCTAssert(
+      label.frame.size.height > 20 && label.frame.size.width <= 20,
+      "sizeToFit should size the view to fit given constrained size")
+    label.numberOfLines = 1
+    label.sizeToFit(containerView.frame.size)
+    XCTAssert(
+      label.frame.size.height > 20 && label.frame.size.width <= 20,
+      "sizeToFit should size the view to fit given constrained size")
+  }
+}