Improve test suite for bibtex

[dieghernan]

This PR increases the test suite for bibtex package (Phase 1: Current state / Testing on #45 ). I tried to cover as many cases as I can, including also some additional .bib files for testing purposes:

• A specific test suite for checking older resolved issues has been included.
• I also included a test on do_read_bib() (tests/testthat/test-do_read_bib.R) reading non-standard BiBTeX entries that is used on https://github.com/ropensci/RefManageR (@mwmclean).

The tests mainly covers the R source code. It seems to be that a lot of the C code is not currently used (¿?).

Additionally, I upgraded testthat version to 3 (this allows the use of snapshots, that would be useful for testing Phase 2) and improved the R-CMD-Check action to increase the number of platforms on which the package is tested.

Any further improvements on the testing welcomed.

PS: Note that neither R not C code has been modified so far.

[dieghernan]

Ping @matthewwiese

[matthewwiese]

If you're looking for additional testing material, try the Collection of Computer Science Bibliographies whose entries contain their BibTeX source. I discovered it thanks to this Academia StackExchange comment some time back. Also, I think increasing coverage of malformed input is important. Currently there appears to be only two cases (1, 2) of error checking; if the effort will be made to rewrite the package then making sure it fails gracefully is crucial.

Otherwise, glad to see your enthusiasm on this!

[dieghernan]

HI @matthewwiese :

I tried to add more test on errors due to unbalanced braces, etc (see also #42 and tests/testthat/test-fatal-errors.R but unfortunately the package crashes. I left them (skipped) as a reminder for future improvements

UPDATE: Now not skipped in #47

[dieghernan]

Hi @coatless , did you have the chance of having a look on this? Regards

[dieghernan]

Thanks @coatless, I made some minor amendments following your comments. Ready for merge