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testthat

Overview

Testing your code can be painful and tedious, but it greatly increases the quality of your code. testthat tries to make testing as fun as possible, so that you get a visceral satisfaction from writing tests. Testing should be addictive, so you do it all the time. To make that happen, testthat:

Provides functions that make it easy to describe what you expect a function to do, including catching errors, warnings, and messages.
Easily integrates in your existing workflow, whether it’s informal testing on the command line, building test suites, or using R CMD check.
Displays test progress visually, showing a pass, fail, or error for every expectation. If you’re using the terminal or a recent version of RStudio, it’ll even colour the output.

testthat draws inspiration from the xUnit family of testing packages, as well as from many of the innovative ruby testing libraries, like rspec, testy, bacon and cucumber.

testthat is the most popular unit testing package for R and is used by thousands of CRAN packages.

If you’re not familiar with testthat, the testing chapter in R packages gives a good overview, along with workflow advice and concrete examples.

Installation

# Install the released version from CRAN
install.packages("testthat")

# Or the development version from GitHub:
# install.packages("pak")
pak::pak("r-lib/testthat")

Usage

The easiest way to get started is with usethis. Assuming you’re in a package directory, just run usethis::use_test("name") to create a test file, and set up all the other infrastructure you need. If you’re using RStudio, press Cmd/Ctrl + Shift + T (or run devtools::test() if not) to run all the tests in a package.

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Version

Install

install.packages('testthat')

Monthly Downloads

442,445

Version

3.2.1.1

License

MIT + file LICENSE

Issues

Pull Requests

Stars

Forks

Repository

https://github.com/r-lib/testthat

Homepage

https://testthat.r-lib.org

Maintainer

Last Published

April 14th, 2024

Functions in testthat (3.2.1.1)

equality-expectations

Does code return the expected value?

evaluate_promise

Evaluate a promise, capturing all types of output.

The building block of all expect_ functions

expect_less_than

Deprecated numeric comparison functions

comparison-expectations

Does code return a number greater/less than the expected value?

Does code return a vector with the specified length?

Does code throw an error, warning, message, or other condition?

expect_setequal

Does code return a vector containing the expected values?

Does code return a vector with (given) names?

describe: a BDD testing language

context_start_file

Start test context from a file name

Compare two directory states.

expect_no_error

Does code run without error, warning, message, or other condition?

expect_equivalent

Is an object equal to the expected value, ignoring attributes?

default_reporter

Retrieve the default reporter

Provide human-readable comparison of two objects

Capture output to console

Does an object inherit from a given class?

expect_snapshot_file

Snapshot testing for whole files

expect_invisible

Does code return a visible or invisible object?

expect_known_output

Expectations: is the output or the value equal to a known good value?

Does code return a vector with the expected size and/or prototype?

Expect that a condition holds.

expect_snapshot_value

Snapshot testing for values

expect_reference

Does code return a reference to the expected object?

Capture the state of a directory.

Does code return NULL?

Does a string match a regular expression?

expect_snapshot_output

Snapshot helpers

Default expectations that always succeed or fail.

inheritance-expectations

Does code return an object inheriting from the expected base type, S3 class, or S4 class?

Does code print output to the console?

Describe the context of a set of tests.

Construct an expectation object

Tools for testing expectations

is_informative_error

Is an error informative?

expect_output_file

Expectations: is the output or the value equal to a known good value?

logical-expectations

Does code return TRUE or FALSE?

Determine testing status

make_expectation

Make an equality test.

Superseded skip functions

expect_snapshot

Snapshot testing

Does code execute silently?

Run all tests in a package

reporter-accessors

Get and set active reporter.

Find reporter object given name or object.

Temporarily change the active testthat edition

Run tests in a single file

expect_cpp_tests_pass

Do C++ tests past?

Locate a file in the testing directory

local_mocked_bindings

Run code after all test files

Run code before/after tests

takes_less_than

Does code take less than the expected amount of time to run?

Use Catch for C++ Unit Testing

local_test_context

Locally set options for maximal test reproducibility

local_snapshotter

Instantiate local snapshotting context

Objects exported from other packages

Try evaluating an expressing multiple times until it succeeds.

Quasi-labelling

snapshot_accept

Snapshot management

find_test_scripts

Find test files

local_test_directory

Locally set test directory options

Watch a directory for changes (additions, deletions & modifications).

Source a file, directory of files, or various important subsets

testthat-package

An R package to make testing fun!

Negate an expectation

Run all tests in a directory

set_state_inspector

State inspected

Set maximum number of test failures allowed before aborting the run

Generate default testing environment.

Old-style expectations.

Test package examples

Mock functions in a package.

testthat_examples

Retrieve paths to built-in example test files

testthat_results

Create a testthat_results object from the test results as stored in the ListReporter results field.

testthat_tolerance

Default numeric tolerance

Test reporter: start recovery.

Check reporter: 13 line summary of problems

Multi reporter: combine several reporters in one.

ProgressReporter

Test reporter: interactive progress bar of errors.

LocationReporter

Test reporter: location

List reporter: gather all test results along with elapsed time and file information.

MinimalReporter

Test reporter: minimal.

RStudioReporter

Test reporter: RStudio

Test reporter: summary of errors in jUnit XML format.

Test reporter: fail at end.

capture_condition

Capture conditions, including messages, warnings, expectations, and errors.

Test reporter: TAP format.

TeamcityReporter

Test reporter: Teamcity format.

Test reporter: stop on error

SummaryReporter

Test reporter: summary of errors.

Test reporter: gather all errors silently.

Manage test reporting

Watches code and tests for changes, rerunning tests as appropriate.

auto_test_package

Watches a package for changes, rerunning tests as appropriate.