`join`ing two indexes raises a `AssertionError`

[keewis]

When trying to join two partially overlapping RasterIndexes, a AssertionError is raised. The difference is exactly half the step size, so maybe there's a corner and a center transform involved?

import rasterix
import affine

transform1 = affine.Affine.from_gdal(399955.0, 10.0, 0.0, 5500025.0, 0.0, -10.0)
transform2 = affine.Affine.from_gdal(399955.0, 10.0, 0.0, 5497625.0, 0.0, -10.0)

index1 = rasterix.RasterIndex.from_transform(transform1, width=256, height=256)
index2 = rasterix.RasterIndex.from_transform(transform2, width=256, height=256)

index1.join(index2, how="inner") # AssertionError

Full traceback:

---------------------------------------------------------------------------
AssertionError                            Traceback (most recent call last)
Cell In[1], line 10
      7 index1 = rasterix.RasterIndex.from_transform(transform1, width=256, height=256)
      8 index2 = rasterix.RasterIndex.from_transform(transform2, width=256, height=256)
---> 10 index1.join(index2, how="inner")

File .../.pixi/envs/dev/lib/python3.13/site-packages/rasterix/raster_index.py:757, in RasterIndex.join(self, other, how)
    754 else:
    755     raise NotImplementedError(f"{how=!r} not implemented yet for RasterIndex.")
--> 757 return self._new_with_bbox(new_bbox)

File .../.pixi/envs/dev/lib/python3.13/site-packages/rasterix/raster_index.py:733, in RasterIndex._new_with_bbox(self, bbox)
    731 # TODO: set xdim, ydim explicitly
    732 new_index = self.from_transform(new_affine, width=Nx, height=Ny)
--> 733 assert new_index.bbox == bbox
    734 return new_index

AssertionError: 

[dcherian]

Thanks! I must only be testing very simple cases

rasterix/tests/test_raster_index.py

Line 392 in fc10799

def test_align():

[dcherian]

Actually, I don't understand what the desired behaviour is here. Shall we return empty DataArrays analogous to

xr.align(xr.Dataset(coords={"x": [0, 1]}), xr.Dataset(coords={"x": [0.5, 1.5]}), join="inner")

EDIT: I'm wrong, there is some overlap here.