[Rd] Potential bug in utils::citation()

[Zhian Kamvar]

Hi,

I believe the function utils::citation() will fail if the package specified has two or more citation entries in the current R-devel. The following error is issued:

'missing' can only be used for arguments 

I have created a working example on github [0] that is build using R-devel on travis-ci [1]. Jim Hester has potentially identified [2] the source of the problem as being from a commit on the 27th [3, 4]. I do not have R-devel built on my machine, but I believe this error can be reproduced on the current R-devel with:

if (require("boot") & require("utils")) utils::citation("boot")

Background:

My package poppr suddenly started failing check on R-devel during a weekly travis-ci job [5] due to the error above. Another package of mine, ezec, passed [6]. Both contain calls to utils::citation() within the vignettes, but  poppr has two citations and ezec only has one (called from another package).

Thanks,
Zhian

[0]: https://github.com/zkamvar/citest
[1]: https://travis-ci.org/zkamvar/citest/jobs/217874351
[2]: https://github.com/wch/r-source/commit/7890e9e87d44f85ab76c0e786036a191eacd71d1
[3]: https://svn.r-project.org/R/trunk@72419
[4]: https://github.com/wch/r-source/commit/7890e9e87d44f85ab76c0e786036a191eacd71d1
[5]: https://travis-ci.org/grunwaldlab/poppr/jobs/216452458
[6]: https://travis-ci.org/grunwaldlab/ezec/jobs/216452916

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Zhian N. Kamvar, Ph. D.
Postdoctoral Researcher (Everhart Lab)
Department of Plant Pathology
University of Nebraska-Lincoln