FIX: Interpret empty string in SliceThickness DICOM field as missing (default to 1)

[mattcieslak]

I was running into an issue where sometimes the value for SliceThickness was an empty string instead of None. I'm not sure if this is the right place to add the change, though.

[codecov-io]

Codecov Report

Merging #652 into master will not change coverage.
The diff coverage is 0%.

@@           Coverage Diff           @@
##           master     #652   +/-   ##
=======================================
  Coverage   88.82%   88.82%           
=======================================
  Files          92       92           
  Lines       11285    11285           
  Branches     1850     1850           
=======================================
  Hits        10024    10024           
  Misses        926      926           
  Partials      335      335

Impacted Files	Coverage Δ
nibabel/nicom/dicomwrappers.py	90.73% <0%> (ø)	⬆️

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[coveralls]

Coverage remained the same at 91.794% when pulling 9a91995 on mattcieslak:master into bb8c6fa on nipy:master.

[effigies]

Hi, sorry for the slow response. Is there any chance of providing a test DICOM file that will hit this code path?

[effigies]

Hi @mattcieslak, just wanted to see if you have a test file that exhibits this property? Synthetic or anonymized would both work fine.

[mattcieslak]

I'll check to see if I can find this again, I think it might have been a non-image dicom that was causing the trouble.

[effigies]

Hi @mattcieslak, sorry to be a nuisance, but I'm going to try to release next Monday, so it'd be great to get this in ASAP.

[mattcieslak]

Found the file and am checking with the study owners what the sharing policy is. I'm thinking this might just be a corrupt dicom because the rest of the files from that series have valid numbers for slice thickness

[effigies]

Awesome. Thanks for your patience on this. (Failing tests are the usual AppVeyor weirdness.)