fix(sahi): Fix Polygon Repair and Empty Polygon Issues

[SunHao-AI]

• Added repair_polygon and repair_multipolygon functions to repair invalid polygons and multipolygons.
• Implemented coco_segmentation_to_shapely function to convert COCO format segmentation data into Shapely objects.
• Enhanced the get_union_polygon function to handle empty polygons using the newly implemented conversion and repair methods.

[fcakyon]

@SunHao-AI can you please fix the failing tests 🤗

[mario-dg]

@fcakyon, I need this fix, as it probably also addresses #1094 but with a cleaner implementation. Should I open a new PR, implement the changes and make sure the tests are running?

[SunHao-AI]

您能否修复失败的测试 🤗

def coco_segmentation_to_shapely(
    segmentation: Union[List, List[List]]
):
    """
    Fix segment data in COCO format

    :param segmentation: segment data in COCO format
    :return:
    """
    if isinstance(segmentation, List) and all([not isinstance(seg, List) for seg in segmentation]):
        segmentation = [segmentation]
    elif isinstance(segmentation, List) and all([isinstance(seg, List) for seg in segmentation]):
        pass
    else:
        raise ValueError("segmentation must be list or list[list]")

    polygon_list = []

    for coco_polygon in segmentation:
        point_list = list(zip(coco_polygon[::2], coco_polygon[1::2]))
        shapely_polygon = Polygon(point_list)
        polygon_list.append(repair_polygon(shapely_polygon))

    shapely_multipolygon = repair_multipolygon(MultiPolygon(polygon_list))
    return shapely_multipolygon

[SunHao-AI]

，我需要这个修复程序，因为它可能也解决了 #1094，但实现了更简洁。我应该打开一个新的 PR，实施更改并确保测试正在运行吗？

ok

[mario-dg]

@SunHao-AI, if you are already at it, you might just make the fix yourself, as you already posted the solution 😄

[gboeer]

The first checks fail because of the type annotation, i.e. tuple is not available in older python versions as a type annotation. You can either use Tuple from the typing package as has been done in the rest of the codebase, or have to implement fallbacks for older python versions.