public function getLintErrorForNode()

in src/Linters/DontHaveTwoEmptyLinesInARowLinter.hack [20:78]
48 lines of code
12 McCabe index (conditional complexity)

  public function getLintErrorForNode(
    this::TContext $context,
    this::TNode $token,
  ): ?ASTLintError {
    if ($this->entireScriptIsClean($context)) {
      return null;
    }

    if (!Str\contains($token->getCode(), \PHP_EOL.\PHP_EOL)) {
      // We check for 2 eols, because the previous token may have the first.
      return null;
    }

    $eol_count = $this->getAST()
      ->getPreviousToken($token)
      ?->getTrailing()
      ?->getLast()
      |> $$ is EndOfLine ? 1 : 0;

    $remove_leading = vec[];
    $remove_trailing = vec[];

    foreach ($token->getLeading()->toVec() as $trivia) {
      if ($trivia is EndOfLine) {
        $eol_count++;
        if ($eol_count >= 3) {
          $remove_leading[] = $trivia;
        }
      } else {
        $eol_count = 0;
      }
    }

    // We don't check the boundary with the next token.
    // This will be checked by the loop above when linting
    // that token instead.
    $eol_count = 0;
    foreach ($token->getTrailing()->toVec() as $trivia) {
      if ($trivia is EndOfLine) {
        $eol_count++;
        if ($eol_count >= 3) {
          $remove_trailing[] = $trivia;
        }
      } else {
        $eol_count = 0;
      }
    }

    if (C\is_empty($remove_leading) && C\is_empty($remove_trailing)) {
      return null;
    }

    return new ASTLintError(
      $this,
      "Don't have two empty lines in a row",
      $token,
      () ==> static::removeTrivia($token, $remove_leading, $remove_trailing),
    );
  }