[CM - 913] Added lineHeight mutator method

Author: PanchamiShenoy

Sources/YMatterType/Typography/Typography+Mutators.swift

@@ -60,6 +60,27 @@ public extension Typography {
             isFixed: isFixed
         )
     }
+    
+    /// Returns a copy of the Typography but with the new `lineHeight` applied.
+    /// - Parameter value: the line height to use
+    /// - Returns: an updated copy of the Typography
+    func lineHeight(_ value: CGFloat) -> Typography {
+        if lineHeight == value { return self }
+        
+        return Typography(
+            fontFamily: fontFamily,
+            fontWeight: fontWeight,
+            fontSize: fontSize,
+            lineHeight: value,
+            letterSpacing: letterSpacing,
+            paragraphIndent: paragraphIndent,
+            paragraphSpacing: paragraphSpacing,
+            textCase: textCase,
+            textDecoration: textDecoration,
+            textStyle: textStyle,
+            isFixed: isFixed
+        )
+    }
 
     /// Returns a copy of the Typography but with `isFixed` set to `true`
     var fixed: Typography {

Tests/YMatterTypeTests/Typography/Typography+MutatorsTests.swift

@@ -53,6 +53,12 @@ final class TypographyMutatorsTests: XCTestCase {
             _test(original: $0, modified: $0.fontSize(newFontSize), fontSize: newFontSize)
         }
     }
+    
+    func testLineHeight() {
+        types.forEach {
+            _test(original: $0, modified: $0.lineHeight($0.lineHeight + 1), lineHeight: ($0.lineHeight + 1))
+        }
+    }
 
     func testFixed() {
         types.forEach {
@@ -89,13 +95,15 @@ final class TypographyMutatorsTests: XCTestCase {
         modified: Typography,
         weight: Typography.FontWeight? = nil,
         fontSize: CGFloat? = nil,
+        lineHeight: CGFloat? = nil,
         isFixed: Bool? = nil,
         letterSpacing: CGFloat? = nil,
         textCase: Typography.TextCase? = nil,
         textDecoration: Typography.TextDecoration? = nil
     ) {
         let weight = weight ?? original.fontWeight
         let fontSize = fontSize ?? original.fontSize
+        let lineHeight = lineHeight ?? original.lineHeight
         let isFixed = isFixed ?? original.isFixed
         let kerning = letterSpacing ?? original.letterSpacing
         let textCase = textCase ?? original.textCase
@@ -104,14 +112,14 @@ final class TypographyMutatorsTests: XCTestCase {
         // fontWeight, fontSize, isFixed, letterSpacing, textCase, and textDecoration should be as expected
         XCTAssertEqual(modified.fontWeight, weight)
         XCTAssertEqual(modified.fontSize, fontSize)
+        XCTAssertEqual(modified.lineHeight, lineHeight)
         XCTAssertEqual(modified.isFixed, isFixed)
         XCTAssertEqual(modified.letterSpacing, kerning)
         XCTAssertEqual(modified.textCase, textCase)
         XCTAssertEqual(modified.textDecoration, textDecoration)
 
         // the other variables should be the same
         XCTAssertEqual(modified.fontFamily.familyName, original.fontFamily.familyName)
-        XCTAssertEqual(modified.lineHeight, original.lineHeight)
         XCTAssertEqual(modified.textStyle, original.textStyle)
         XCTAssertEqual(modified.paragraphIndent, original.paragraphIndent)
         XCTAssertEqual(modified.paragraphSpacing, original.paragraphSpacing)