RUnit

RUnit is a testing package for R code, inspired by the xUnit family of testing tools.

Originally implemented by Thomas Koenig, Klaus Juenemann, and Matthias Burger, this package has served the R community for over a decade.

Since RUnit is no longer actively developed, I provide maintenance of this package mostly to support older projects that still rely on RUnit.

Using RUnit

To make RUnit work with R CMD check, create a following file in the tests subdirectory. This would run the actual tests stored in the packages inst/tests subdirectory.

# Our package. Used for the test suite name
pkgname <- "your package name"
require(pkgname, quietly=TRUE, character.only=TRUE) || stop("package '", pkgname, "' not found")

# How to determine which files to load (have to start with test_ and end with .R)
pattern <- "^test_.*\\.R$"

# Which functions to run. Have to start with 'test.'
testFunctionRegexp = "^test.+"

# Path to the unit tests folder in the package
dir <- system.file(subdir, package=pkgname)

# Define RUnit test suite
suite <- defineTestSuite(name=paste(pkgname, "RUnit Tests"),
                         dirs=dir,
                         testFileRegexp=pattern,
                         testFuncRegexp = testFunctionRegexp,
                         rngKind="default",
                         rngNormalKind="default")

# Run tests
result <- runTestSuite(suite)

# Display result tests on the console
printTextProtocol(result)

# Write results in JUnit-like xml format
printJUnitProtocol(result, fileName="junit.xml")

A typical unit test would then live for example in inst/tests/test.operations.R. Each such file can contain multiple functions like so:

test.additionWorks <- function() {
  checkEquals(2, 1+1, "one plus one must be two")
}

test.divisionByZeroFails <- function() {
  checkException(1/0, "division by zero is expected to fail")
}