Frame.parseV8 constructor Null safety

Implementation

factory Frame.parseV8(String frame) => _catchFormatException(frame, () {
      var match = _v8Frame.firstMatch(frame);
      if (match == null) return UnparsedFrame(frame);

      // v8 location strings can be arbitrarily-nested, since it adds a layer
      // of nesting for each eval performed on that line.
      Frame parseLocation(String location, String member) {
        var evalMatch = _v8EvalLocation.firstMatch(location);
        while (evalMatch != null) {
          location = evalMatch[1]!;
          evalMatch = _v8EvalLocation.firstMatch(location);
        }

        if (location == 'native') {
          return Frame(Uri.parse('native'), null, null, member);
        }

        var urlMatch = _v8UrlLocation.firstMatch(location);
        if (urlMatch == null) return UnparsedFrame(frame);

        final uri = _uriOrPathToUri(urlMatch[1]!);
        final line = int.parse(urlMatch[2]!);
        final columnMatch = urlMatch[3];
        final column = columnMatch != null ? int.parse(columnMatch) : null;
        return Frame(uri, line, column, member);
      }

      // V8 stack frames can be in two forms.
      if (match[2] != null) {
        // The first form looks like " at FUNCTION (LOCATION)". V8 proper
        // lists anonymous functions within eval as "<anonymous>", while IE10
        // lists them as "Anonymous function".
        return parseLocation(
            match[2]!,
            match[1]!
                .replaceAll('<anonymous>', '<fn>')
                .replaceAll('Anonymous function', '<fn>')
                .replaceAll('(anonymous function)', '<fn>'));
      } else {
        // The second form looks like " at LOCATION", and is used for
        // anonymous functions.
        return parseLocation(match[3]!, '<fn>');
      }
    });