html_url,issue_url,id,node_id,user,created_at,updated_at,author_association,body,reactions,performed_via_github_app,issue https://github.com/pydata/xarray/pull/3649#issuecomment-568142720,https://api.github.com/repos/pydata/xarray/issues/3649,568142720,MDEyOklzc3VlQ29tbWVudDU2ODE0MjcyMA==,4801430,2019-12-21T02:03:21Z,2019-12-21T02:03:21Z,CONTRIBUTOR,Done,"{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,540601428 https://github.com/pydata/xarray/pull/3649#issuecomment-568109804,https://api.github.com/repos/pydata/xarray/issues/3649,568109804,MDEyOklzc3VlQ29tbWVudDU2ODEwOTgwNA==,4801430,2019-12-20T22:23:56Z,2019-12-20T22:23:56Z,CONTRIBUTOR,Will do!,"{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,540601428 https://github.com/pydata/xarray/pull/3649#issuecomment-568067947,https://api.github.com/repos/pydata/xarray/issues/3649,568067947,MDEyOklzc3VlQ29tbWVudDU2ODA2Nzk0Nw==,4801430,2019-12-20T19:56:19Z,2019-12-20T19:56:56Z,CONTRIBUTOR,"yeah - that makes sense! So if `fill_value is None` then we can have the additional check to make sure it's a complete hypercube. The next question, like you mention, is whether we change the default `fill_value` to `None`. It seems like that would make the most sense to me. That way, the default is to throw an error with incomplete hypercubes (the previous behavior), and the incompleteness is only allowed if you provide a value to fill with. But I can see your point about having the default be `dtypes.NA` for consistency with `merge` and `concat`. Thoughts?","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,540601428