Possible bug on ccdproc.ImageFileCollection

[simontorres]

Summary

Last Saturday 26th my automated builds started to fail for no apparent reason. Today I have tracked it to ImageFileCollection from ccdproc version 1.3.0.post1, here is a ugly sample code that can reproduce the error.

Minimum sample code

For running it you will need this directory and replace full path into full_path variable

import os
from ccdproc import ImageFileCollection

full_path = '/replace/with/full/path/to/ref_comp'

file_collection = ImageFileCollection(full_path)

file_collection_pd = file_collection.summary.to_pandas()

# this filtering should leave just one file in the collection.
fc = file_collection_pd[
    (file_collection_pd['object'] == 'HgArNe') & 
    (file_collection_pd['wavmode'] == '400 m2')]


if len(fc) == 1:
    print("The file name should print without blanks around =={:s}==".format(fp.file.to_string(index=False)))

    print("Notice the blank?")
    print(os.path.join(full_path, file_collection_pd.file.to_string(index=False)))

else:
    print("please make sure only one file will match the filtering conditions")

In my case when I run this with ccdproc.__version == '1.3.0' it works as expected. File name does not start with blank space.

(goodman_pipeline) [simon@ctioy9 sandbox]$ python3.6 -c "import ccdproc; print(ccdproc.__version__)"
1.3.0
(goodman_pipeline) [simon@ctioy9 sandbox]$ python3.6 testing_collection.py 
The file name should print without blanks around ==goodman_comp_400M2_GG455_HgArNe.fits==
Notice the blank?
/data/simon/development/soar/goodman_pipeline/goodman_pipeline/data/ref_comp/goodman_comp_400M2_GG455_HgArNe.fits

With ccdproc.__version == '1.3.0.post1'

(goodman_pipeline) [simon@ctioy9 sandbox]$ python3.7 -c "import ccdproc; print(ccdproc.__version__)"
1.3.0.post1
(goodman_pipeline) [simon@ctioy9 sandbox]$ python3.7 testing_collection.py 
The file name should print without blanks around == goodman_comp_400M2_GG455_HgArNe.fits==
Notice the blank?
/data/simon/development/soar/goodman_pipeline/goodman_pipeline/data/ref_comp/ goodman_comp_400M2_GG455_HgArNe.fits

Versions

(goodman_pipeline) [simon@ctioy9 sandbox]$ python3.6 versions.py 
2.0.2
1.3.0
1.13.3
(goodman_pipeline) [simon@ctioy9 sandbox]$ python3.7 versions.py 
3.1.1
1.3.0.post1
1.15.2
(goodman_pipeline) [simon@ctioy9 sandbox]$ cat versions.py 
import astropy
print(astropy.__version__)
import ccdproc
print(ccdproc.__version__)
import numpy
print(numpy.__version__)
(goodman_pipeline) [simon@ctioy9 sandbox]$ 

[simontorres]

I just realized it could be pandas actually. Will update...

[simontorres]

Yes definitely is a pandas bug. It matches with the release of pandas 0.24.0