This fixes a bug and adds a feature

Sources/Splash/Syntax/SyntaxHighlighter.swift

@@ -35,8 +35,9 @@ public struct SyntaxHighlighter<Format: OutputFormat> {
                 state = (token, type)
                 return
             }
-
-            builder.addToken(token, ofType: type)
+            if token != whitespace {
+                builder.addToken(token, ofType: type)
+            }
             builder.addWhitespace(whitespace)
             state = nil
         }

Sources/Splash/Theming/Font.swift

@@ -31,6 +31,12 @@ public struct Font {
         resource = .system
         self.size = size
     }
+
+    /// Initialize an instance with an existing, custom, font.
+    public init(_ font: Loaded) {
+        resource = .preloaded(font)
+        self.size = Double(font.pointSize)
+    }
 }
 
 public extension Font {

Tests/SplashTests/Tests/AttributedStringTests.swift

@@ -0,0 +1,58 @@
+#if !os(Linux)
+
+import Foundation
+import XCTest
+import Splash
+
+final class AttributedStringOutputFormatTests: SplashTestCase {
+    private var highlighter: SyntaxHighlighter<AttributedStringOutputFormat>!
+
+    override func setUp() {
+        super.setUp()
+        highlighter = SyntaxHighlighter(format: AttributedStringOutputFormat(theme: Theme.presentation(withFont: .init(size: 15))))
+    }
+
+    func testBasicAttributedStringOutputMatchesInput() {
+        let input = """
+        public struct Test: SomeProtocol {
+            func hello() -> Int { return 7 }
+        }
+        """
+        let output = highlighter.highlight(input)
+        XCTAssertEqual(input, output.string)
+    }
+
+    func testNewlinesAttributedStringOutputMatchesInput() {
+        let input = """
+
+        typealias a = b
+        typealias b = c
+
+        print("hello")
+        """
+        let output = highlighter.highlight(input)
+        XCTAssertEqual(input, output.string)
+    }
+
+    func testInnerNewlinesAttributedStringOutputMatchesInput() {
+        let input = """
+        typealias a = b
+        typealias b = c
+
+        print("hello")
+
+        print("hello")
+        print("hello")
+
+
+        print("hello")
+        """
+        let output = highlighter.highlight(input)
+        XCTAssertEqual(input, output.string)
+    }
+
+    func testAllTestsRunOnLinux() {
+    }
+}
+
+#endif