refactor: Use early return pattern to avoid nested conditions

[jongwooo]

Signed-off-by: jongwooo jongwooo.han@gmail.com
Issue #557

Description

Return early is the way of writing functions or methods so that the expected positive result is returned at the end of the function and the rest of the code terminates the execution (by returning or throwing an exception) when conditions are not met.

See actions/cache#1012, actions/setup-node#639

In utils.ts:

AS-IS

export function isCacheFeatureAvailable(): boolean {
  if (!cache.isFeatureAvailable()) {
    if (isGhes()) {
      throw new Error(
        'Caching is only supported on GHES version >= 3.5....'
      );
    } else {
      core.warning(
        'The runner was not able to...'
      );
    }

    return false;
  }

  return true;
}

TO-BE

export function isCacheFeatureAvailable(): boolean {
  if (cache.isFeatureAvailable()) {
    return true;
  }

  if (isGhes()) {
    throw new Error(
      'Caching is only supported on GHES version >= 3.5...'
    );
  }

  core.warning(
    'The runner was not able to...'
  );
  return false;
}

Check list:

• Mark if documentation changes are required.
• Mark if tests were added or updated to cover the changes.