R

The R language has two common methods of assignment. The = and <- binary operators are semantically equivalent in most cases, so which to use largely comes down to convention for the particular project. At times it may be desirable to convert between the two styles. Converting all instances of <- to use = assignment is fairly straightforward. <- only performs assignment and is unique, so one can simply do a regular expression replacement for all occurrences of <-.

A deeper dive into how covr works, particularly how it deals with collecting coverage from multiple child R processes.

Code coverage records whether or not each line of code in a package is executed by the package's tests. While it does not check whether a given program or test executes properly it does reveal areas of the code which are untested. Coverage has a long …

This talk demonstrated the use of devtools for developing Bioconductor packages, in particular showing the use of `use_bioc` in travis and the introduction of the `install_bioc()` functions in devtools.

A talk on my R packages, lintr and covr

Track and report code coverage for your package and (optionally) upload the results to a coverage service like [Codecov](http://codecov.io) or [Coveralls](http://coveralls.io).

Being primarily a statistical language R lacks a number of common code analysis tools available for languages used more often for general programming. Testing has been done in the R source from very early on (Martin Maechler started adding tests on April 9th, 1998, 17 years ago!) However most of this testing was ad hoc, either requiring visual examination of the outputs, or simply testing current vs previous outputs. The RUnit (2005), svUnit (2009) and testthat (2009) packages brought more formal unit testing into R community.