Trace foldFrames()

in lib/src/trace.dart [285:328]

• 31 lines of code
• 16 McCabe index (conditional complexity)

  Trace foldFrames(bool Function(Frame) predicate, {bool terse = false}) {
    if (terse) {
      var oldPredicate = predicate;
      predicate = (frame) {
        if (oldPredicate(frame)) return true;

        if (frame.isCore) return true;
        if (frame.package == 'stack_trace') return true;

        // Ignore async stack frames without any line or column information.
        // These come from the VM's async/await implementation and represent
        // internal frames. They only ever show up in stack chains and are
        // always surrounded by other traces that are actually useful, so we can
        // just get rid of them.
        // TODO(nweiz): Get rid of this logic some time after issue 22009 is
        // fixed.
        if (!frame.member!.contains('<async>')) return false;
        return frame.line == null;
      };
    }

    var newFrames = <Frame>[];
    for (var frame in frames.reversed) {
      if (frame is UnparsedFrame || !predicate(frame)) {
        newFrames.add(frame);
      } else if (newFrames.isEmpty || !predicate(newFrames.last)) {
        newFrames.add(Frame(frame.uri, frame.line, frame.column, frame.member));
      }
    }

    if (terse) {
      newFrames = newFrames.map((frame) {
        if (frame is UnparsedFrame || !predicate(frame)) return frame;
        var library = frame.library.replaceAll(_terseRegExp, '');
        return Frame(Uri.parse(library), null, null, frame.member);
      }).toList();

      if (newFrames.length > 1 && predicate(newFrames.first)) {
        newFrames.removeAt(0);
      }
    }

    return Trace(newFrames.reversed, original: original.toString());
  }