E0162: 'await' is only allowed in async functions

The await operator can be used in async functions and in modules at the top level. It is a syntax error to use the await operator in a non-async function:

function readConfig(configFilePath) {
  let data = await fs.promises.readFile(
    configFilePath,
    "utf-8",
  );
  return parseConfig(data);
}

async function takeOverTheWorld() {
  let config = readConfig(CONFIG_FILE);
  if (config.prettyPlease) {
    await reallyTakeOverTheWorld();
  }
}

To fix this error, declare the function as async, ensuring that callers use await too:

async function readConfig(configFilePath) {
  let data = await fs.promises.readFile(
    configFilePath,
    "utf-8",
  );
  return parseConfig(data);
}

async function takeOverTheWorld() {
  let config = await readConfig(CONFIG_FILE);
  if (config.prettyPlease) {
    await reallyTakeOverTheWorld();
  }
}

Introduced in quick-lint-js version 0.3.0.

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