 
 private let typesetter = Typesetter()
 
-private func asciiMarked(_ strings: [String]) -> [String] {
-  return strings + ["a"]
+private func asciiMarked(_ strings: [String]) -> [[Unicode.UTF16.CodeUnit]] {
+  return utf16Chars(strings + ["a"])
 }
 
-private func emojiMarked(_ strings: [String]) -> [String] {
-  return strings + ["\u{1F600}"]
+private func emojiMarked(_ strings: [String]) -> [[Unicode.UTF16.CodeUnit]] {
+  return utf16Chars(strings + ["\u{1F600}"])
 }
 
 private func utf16Chars(_ array: [String]) -> [[Unicode.UTF16.CodeUnit]] {


  func testSimpleLigatureChars() {
    let runs = typesetter.fontGlyphRunsWithLigatures(
      nvimUtf16Cells: utf16Chars(
        emojiMarked(["-", "-", ">", "a"])
      ),
      startColumn: 0,
      offset: offset,
      font: fira,


  func testAccentedChars() {
    let runs = typesetter.fontGlyphRunsWithoutLigatures(
      nvimUtf16Cells: emojiMarked(["ü", "î", "ñ"]),
      startColumn: 20,
      offset: offset,
      font: defaultFont,
