scanDartDirectives function

List<DartDirective> scanDartDirectives(String source)

The directives of source, in order.

Implementation

List<DartDirective> scanDartDirectives(String source) {
  final tokens = _Tokenizer(source).tokens();
  final directives = <DartDirective>[];
  var depth = 0;
  _Token? previous;
  for (var i = 0; i < tokens.length; i++) {
    final token = tokens[i];
    if (token.kind == _TokenKind.punct) {
      if (token.text == '{') depth++;
      if (token.text == '}' && depth > 0) depth--;
    }
    final atStatementStart =
        previous == null ||
        (previous.kind == _TokenKind.punct &&
            (previous.text == ';' || previous.text == '}'));
    if (depth == 0 &&
        atStatementStart &&
        token.kind == _TokenKind.ident &&
        (token.text == 'import' ||
            token.text == 'export' ||
            token.text == 'part')) {
      var kind = switch (token.text) {
        'import' => DartDirectiveKind.import,
        'export' => DartDirectiveKind.export,
        _ => DartDirectiveKind.part,
      };
      final uris = <String>[];
      int? line;
      var j = i + 1;
      if (kind == DartDirectiveKind.part &&
          j < tokens.length &&
          tokens[j].kind == _TokenKind.ident &&
          tokens[j].text == 'of') {
        kind = DartDirectiveKind.partOf;
        j++;
      }
      for (; j < tokens.length; j++) {
        final t = tokens[j];
        if (t.kind == _TokenKind.punct && t.text == ';') break;
        if (t.kind == _TokenKind.string) {
          uris.add(t.text);
          line ??= t.line;
        }
      }
      directives.add(DartDirective(kind, uris, line ?? token.line));
      i = j;
      previous = j < tokens.length ? tokens[j] : null;
      continue;
    }
    previous = token;
  }
  return directives;
}