static H3Index nextCell()

in h3_polyfill.c [290:318]

• 22 lines of code
• 6 McCabe index (conditional complexity)

static H3Index nextCell(H3Index cell) {
    int res = H3_GET_RESOLUTION(cell);
    while (true) {
        // If this is a base cell, set to next base cell (or H3_NULL if done)
        if (res == 0) {
            return baseCellNumToCell(H3_GET_BASE_CELL(cell) + 1);
        }

        // Faster cellToParent when we know the resolution is valid
        // and we're only moving up one level
        H3Index parent = cell;
        H3_SET_RESOLUTION(parent, res - 1);
        H3_SET_INDEX_DIGIT(parent, res, H3_DIGIT_MASK);

        // If not the last sibling of parent, return next sibling
        Direction digit = H3_GET_INDEX_DIGIT(cell, res);
        if (digit < INVALID_DIGIT - 1) {
            H3_SET_INDEX_DIGIT(cell, res,
                               digit + ((H3_EXPORT(isPentagon)(parent) &&
                                         digit == CENTER_DIGIT)
                                            ? 2  // Skip missing pentagon child
                                            : 1));
            return cell;
        }
        // Move up to the parent for the next loop iteration
        res--;
        cell = parent;
    }
}