Fix #1 - Not respecting lineSpacing when set

There was an issue where if you set some custom attributes before
setting attributedText on the label, it wouldn't keep those properties
in the attributedString. Now when you set lineSpacing, and then set
attributedText on the label, it'll pull the properties already setup and
append them to the attributedString you're putting in.

Example/Nantes/ViewController.swift

@@ -32,6 +32,7 @@ final class ViewController: UIViewController {
         case truncatedLinkText = "Truncated link text with a longer body so we'll truncate it\nMaybe a newline for good measure"
         case transitInfo = "UA450"
         case privacyPolicyText = "By creating an account, you agree to our\nTerms of Service and Privacy Policy"
+        case linespace = "Test string with font and linespace set with some extra content in there so it'll wrap around and have multiple lines"
     }
 
     private var strings: [String] = []
@@ -62,6 +63,8 @@ final class ViewController: UIViewController {
         setupStrokedLabel()
         setupTruncatedAttributedToken()
         setupPrivacyPolicyLabel()
+        setupLineSpace()
+        setupUILabelLineSpace()
     }
 
     private func setupTitleLabel() {
@@ -245,6 +248,27 @@ final class ViewController: UIViewController {
         label.addLink(to: URL(string: "https://www.google.com")!, withRange: (text as NSString).range(of: "Privacy Policy"))
         labelStackView.addArrangedSubview(label)
     }
+
+    private func setupLineSpace() {
+        let label: NantesLabel = .init(frame: .zero)
+        label.numberOfLines = 0
+        label.lineSpacing = 40
+        label.font = .systemFont(ofSize: 14.0)
+        label.text = ExampleString.linespace.rawValue
+
+        labelStackView.addArrangedSubview(label)
+    }
+
+    private func setupUILabelLineSpace() {
+        let label: UILabel = .init(frame: .zero)
+        label.numberOfLines = 0
+        let paragraphStyle = NSMutableParagraphStyle()
+        paragraphStyle.lineSpacing = 40
+        let attributedText = NSAttributedString(string: ExampleString.linespace.rawValue, attributes: [NSAttributedString.Key.paragraphStyle: paragraphStyle, NSAttributedString.Key.font: UIFont.systemFont(ofSize: 14.0)])
+        label.attributedText = attributedText
+
+        labelStackView.addArrangedSubview(label)
+    }
 }
 
 extension ViewController: NantesLabelDelegate {

Example/Podfile.lock

@@ -1,5 +1,5 @@
 PODS:
-  - Nantes (0.0.3)
+  - Nantes (0.0.4)
 
 DEPENDENCIES:
   - Nantes (from `../`)
@@ -9,7 +9,7 @@ EXTERNAL SOURCES:
     :path: "../"
 
 SPEC CHECKSUMS:
-  Nantes: 72320e1ac102e6763503c27b2bc01d220f8e4acf
+  Nantes: f7f93de5a749e62f7367f93d2c0f15f4c6dabf09
 
 PODFILE CHECKSUM: 1c8633395754df792140631cc4cd6cb86ec7966b
 

Source/Classes/NantesLabel.swift

@@ -309,11 +309,18 @@ public extension NSAttributedString.Key {
         get {
             return _attributedText
         } set {
-            guard newValue != _attributedText else {
+            let attributes = NSAttributedString.attributes(from: self)
+            guard let updatedText = newValue?.mutableCopy() as? NSMutableAttributedString else {
+                return
+            }
+
+            updatedText.addAttributes(attributes, range: NSRange(location: 0, length: updatedText.length))
+
+            guard updatedText != _attributedText else {
                 return
             }
 
-            _attributedText = newValue
+            _attributedText = updatedText
             setNeedsFramesetter()
             _accessibilityElements = nil
             linkModels = []