function getDisplayName(arg0, arg1, arg2, pageType) {
  let displayName = (arg1 || arg0.slice(arg0.lastIndexOf("/") + 1));

  if (!arg1) {
    // Append parameter brackets to CSS functions
    if ((pageType === "css-function") && !displayName.endsWith("()")) {
      displayName += "()";
    }
  }
  
  return displayName;
}

const TEST_CASE = [
  ["color_value/lab", "", "", "css-function"],
  ["@page/size", "", "", "css-at-rule-descriptor"],
  ["abs()", "", "", "css-function"],
]

for (const caseInput of TEST_CASE) {
  console.log(getDisplayName(...caseInput));
}

/* Expected output:
 * lab()
 * size
 * abs()
 */