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/issues/1988#issuecomment-380137124,https://api.github.com/repos/pydata/xarray/issues/1988,380137124,MDEyOklzc3VlQ29tbWVudDM4MDEzNzEyNA==,291576,2018-04-10T15:12:05Z,2018-04-10T15:12:05Z,CONTRIBUTOR,Yup... looks like that did the trick (for auto_combine and open_mfdataset). I even have a simple test to demonstrate it. PR coming shortly.,"{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,305327479
https://github.com/pydata/xarray/issues/1988#issuecomment-379939574,https://api.github.com/repos/pydata/xarray/issues/1988,379939574,MDEyOklzc3VlQ29tbWVudDM3OTkzOTU3NA==,291576,2018-04-10T00:55:48Z,2018-04-10T00:55:48Z,CONTRIBUTOR,"I'll give it a go tomorrow. My work has gotten to this point now, and I have some unit tests that happen to exercise this edge case.

On a somewhat related note, would a `allow_missing` feature be welcomed in `open_mfdataset()`? I have written up some code that expects a `concat_dim`, and a list of filenames. It will then pass to `open_mfdataset()` only the files (and corresponding concat_dim values) that exists, and then calls `reindex()` with the original concat_dim to have a nan-filled slab where-ever there was a missing file.

Any interest?","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,305327479
https://github.com/pydata/xarray/issues/1988#issuecomment-379904046,https://api.github.com/repos/pydata/xarray/issues/1988,379904046,MDEyOklzc3VlQ29tbWVudDM3OTkwNDA0Ng==,1217238,2018-04-09T21:45:53Z,2018-04-09T21:46:01Z,MEMBER,"@WeatherGod Possibly! As usual, tests are the hard part :)","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,305327479
https://github.com/pydata/xarray/issues/1988#issuecomment-379901414,https://api.github.com/repos/pydata/xarray/issues/1988,379901414,MDEyOklzc3VlQ29tbWVudDM3OTkwMTQxNA==,291576,2018-04-09T21:35:11Z,2018-04-09T21:35:11Z,CONTRIBUTOR,Could the fix be as simple as `if len(datasets) == 1 and dim is None:`?,"{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,305327479
https://github.com/pydata/xarray/issues/1988#issuecomment-375558323,https://api.github.com/repos/pydata/xarray/issues/1988,375558323,MDEyOklzc3VlQ29tbWVudDM3NTU1ODMyMw==,1217238,2018-03-23T06:32:17Z,2018-03-23T06:32:17Z,MEMBER,"Yes, this seems like a bug. `open_mfdataset()` should always concatenate if a `dim` argument is provided explicitly.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,305327479
https://github.com/pydata/xarray/issues/1988#issuecomment-375548064,https://api.github.com/repos/pydata/xarray/issues/1988,375548064,MDEyOklzc3VlQ29tbWVudDM3NTU0ODA2NA==,2443309,2018-03-23T05:18:59Z,2018-03-23T05:18:59Z,MEMBER,"This does seem inconsistent to me. Not that the behavior of concat already works with a single object:

```Python
In [1]: import xarray as xr

In [2]: da = xr.DataArray([1, 2], dims='x', name='foo')

In [3]: xr.concat([da], dim='y')
Out[3]:
<xarray.DataArray 'foo' (y: 1, x: 2)>
array([[1, 2]])
Dimensions without coordinates: y, x
```

The offending line is here:

https://github.com/pydata/xarray/blob/9261601f89c0d3cfc54db16718c82399d95266bd/xarray/core/combine.py#L342-L344

Based on this, I'm surprised my little example with concat works the way it does. In either event, it would be great if someone could spend some time normalizing the behavior here. ","{""total_count"": 1, ""+1"": 1, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,305327479