Test whether Different Functions Return the Same

Installation

For details on how to install KWB-R packages checkout our installation tutorial.

### Optionally: specify GitHub Personal Access Token (GITHUB_PAT)
### See here why this might be important for you:
### https://kwb-r.github.io/kwb.pkgbuild/articles/install.html#set-your-github_pat

# Sys.setenv(GITHUB_PAT = "mysecret_access_token")

# Install package "remotes" from CRAN
if (! require("remotes")) {
  install.packages("remotes", repos = "https://cloud.r-project.org")
}

# Install KWB package 'kwb.test' from GitHub

remotes::install_github("kwb-r/kwb.test")

Usage

Load the package

Define a function using saveArgs() to save arguments and result

squareSum <- function(a, b) {
  result <- a * a + b * b
  saveArgs("squareSum", args = list(a = a, b = b), result = result)
  result
}

# Set global variable TESTMODE to "activate" saveArgs() in squareSum()
TESTMODE <- TRUE

# Call the function with different arguments
squareSum(1, 2)
squareSum(2, 3)
squareSum(-1, -2)

# The arguments and function results were saved here:
dir(file.path(tempdir(), "test"))

# Write a new (wrong) version of the function
squareSum.new <- function(a, b) {
  a * a - b * b
}

# Check if it returns the same results
test_function("squareSum.new", loadArgs("squareSum"))

# If no test data are given, loadArgs is called on the function to test,
# i.e. testing squareSum on the test data created by the same function will
# return TRUE if the function did not change in the meanwhile.
test_function("squareSum")