id,node_id,number,state,locked,title,user,body,created_at,updated_at,closed_at,merged_at,merge_commit_sha,assignee,milestone,draft,head,base,author_association,auto_merge,repo,url,merged_by
779940208,PR_kwDOAMm_X84ufPFw,5984,closed,0,preserve chunked data when creating DataArray from DataArray,19226431,"<!-- Feel free to remove check-list items aren't relevant to your change -->

- [x] Closes #5983 
- [x] Tests added
- [x] Passes `pre-commit run --all-files`
",2021-11-13T18:21:10Z,2022-01-13T18:10:57Z,2022-01-13T17:02:47Z,2022-01-13T17:02:47Z,025906332dd11b07968faeaf8d15170690df240d,,,0,ba847c7fbe4c9ceca2bb787d1c53e939cdb709f7,bc28eda793c3966adbd14f9f105c1e19836300bd,CONTRIBUTOR,,13221727,https://github.com/pydata/xarray/pull/5984,
1020278583,PR_kwDOAMm_X8480Dc3,6889,closed,0,Harmonize returned multi-indexed indexes when applying `concat` along new dimension ,19226431,"- [x] Closes #6881 
- [x] Tests added

In the current implementation, the `concat` function does not ensure that the indexes that belong to the same `MultiIndex` relate to the same `MultiIndex` object in `Dataset.indexes` when concatenating along a new dimension. This becomes a problem as soon as the returned dataset needs to be aligned (for broadcasting, reindexing etc.), see #6881 for example. As far as I understand, this bug was introduced in https://github.com/pydata/xarray/pull/5692 following the idea that the `concat` function should disentangle indexes and dimensions. 

It can be fixed by not removing the index name from the list of indexes which should be merged, see https://github.com/pydata/xarray/blob/9050a8b9efc28142b762475c7285603a87b00e83/xarray/core/concat.py#L493. All indexes contained in this list will get a new index object. Currently, this list only contains the **levels** of a multi-indexed index, not the index name itself. This is removed as it is contained in `dim_names`. Instead of removing all dimension names from this list, I suggest to only remove unlabeled dimensions from this list.",2022-08-08T13:12:45Z,2022-08-25T14:12:55Z,2022-08-25T11:15:54Z,2022-08-25T11:15:54Z,15c61822a061153581e44d9c9387e1a352170919,,,0,08e9b6ebb6b7890b2ebc98474cdd667de13a47ba,790a444b11c244fd2d33e2d2484a590f8fc000ff,CONTRIBUTOR,,13221727,https://github.com/pydata/xarray/pull/6889,