README.md
In Displayr/flipChartTests: Visual unit tests for flipChart and flipStandardCharts

flipChartTests

This package contains only unit tests for flipStandardChart and flipChart. Test outputs are machine-specific, so it is recommended that you use the image files included inside the repository rather than local versions.

Tests are run automatically in CircleCI, after a push to flipChartTests, flipChart, flipStandardCharts or other upstream dependencies. Snapshots will be found in tests/testthat/snapshots. Diffing files are in the diff directory and should be compared against files of the same name that are in the accepted directory.

Tests can be added to the R files in the testthat directory. Convenience functions have been provided in flipChartTests so the tests can be created easily. For example,

pp <- plot_ly(x = 1:10, y = 1:10, trace = "scatter")
expect_true(TestWidget(pp, "test1"))

Only the test file (e.g. tests/testthat/test-background.R) should be committed, not the test outputs (PNG files).

The output from running tests locally are not reliable, and should be compared against the output in CircleCI. If working locally, the dependencies can be set up by

install.packages("devtools")
install.packages("testthat")
require(devtools)
install_github("MangoTheCat/visualTest")
install.packages("webshot")
webshot::install_phantomjs()

Because the snapshots are machine-specific, the first time they are run locally, you may need to delete all files inside tests/testthat/snapshots/accepted before regenerating.

To accept new test outputs, simply delete the existing test output inside tests/testthat/snapshots/accepted and the new outputs will saved in that directory next time the tests are run using devtools::test() or testthat_test_file(<filename>) to run a subset of tests.

Note that you should use devtools::test() rather than devtools::check() as check() will give the same errors and warning but will not generate output PNG files in the repository.

To install from GitHub:

require(devtools)
install_github("Displayr/flipChartTests", dependencies = NA)

If you have not set up a GitHub Personal Access Token, you will likely need to do so to avoid GitHub rate limits, which will manifest as 403 errors when downloading packages via install_github. Please see the documentation in the usethis package or see the instructions here and here.

If you are using Windows, you will need to have a version of Rtools installed that matches your version of R in order to build packages from source. Rtools can be downloaded from here.

Specifying dependencies = NA in install_github will not install packages listed in Suggests in the DESCRIPTION file (some of which may be proprietary and unavailable for download).

If you encounter a problem using the package, please open an issue. To achieve a resolution as quickly as possible, please include a minimal, reproducible example of the bug, along with the exact error message or output you receive and the behavior you expect. Including the output of sessionInfo() in R can be helpful to reproduce the issue. Please see this FAQ, which has a number of useful tips on creating great reproducible examples.