Google Script – findText is not defined

I’m trying to make a script for my Google document so I can format specific paragraphs in some “chat log” segments according to the nickname the paragraph begins with (example: “myNickname: blah blah blah”).

I made a test function to test out findText() but when I execute test(), it returns this error: ReferenceError: findText is not defined test @ Code.gs:21

Here is the complete script:

function onOpen(e) {
  DocumentApp.getUi()
  .createMenu("FORMATTING")
    .addItem("Test", "test")

  .addToUi();
}

function formatNickname(nickname, style) {
  nickname = nickname + ":"; // Dialogue is in a 'chat log' format, so it's displayed as "NICKNAME: Blah blah blah"

  let foundText = findText(nickname); 

  foundText.getText().setTextStyle(style);

  console.log(foundText); // Debug
}

function test() {
  formatNickname("BAB", findText("AA:").getText.getTextStyle()); // The second parameter is for debug reasons. AA is a character with a specific text style.
}

And here is my appsscript.json:

{
  "oauthScopes": [
    "https://www.googleapis.com/auth/documents.currentonly",
    "https://www.googleapis.com/auth/documents"
  ],
  "timeZone": "America/Sao_Paulo",
  "dependencies": {
  },
  "exceptionLogging": "STACKDRIVER",
  "runtimeVersion": "V8"
}

I have Google Apps Script API turned on in my user settings, as instructed in this answer.