Track test coverage for your R package and view reports locally or (optionally) upload the results to codecov or coveralls.
install.packages("covr")
# For devel version
devtools::install_github("r-lib/covr")The easiest way to setup covr on Travis-CI is with usethis.
usethis::use_coverage()A coverage report can be used to inspect coverage for each line in your
package. Using report() requires shiny.
library(covr)
# If run with no arguments implicitly calls `package_coverage()`
report()covr also defines an RStudio Addin,
which runs report() on the active project. This can be used via the addin
menu or by binding the action to a
shortcut, e.g.
Ctrl-Shift-C.
# if `getwd()` is the package's directory.
package_coverage()
# or a package in another directory
cov <- package_coverage("/dir/lintr")
# view results as a data.frame
as.data.frame(cov)
# zero_coverage() shows only uncovered lines.
# If run within RStudio, `zero_coverage()` will open a marker pane with the
# uncovered lines.
zero_coverage(cov)If you are already using Travis-CI add the
following to your project's .travis.yml to track your coverage results
over time with Codecov.
r_github_packages:
- r-lib/covr
after_success:
- Rscript -e 'covr::codecov()'If you are using Appveyor CI, and are not using
Travis-CI at the same time, then you can add the
lines below to your project's appveyor.yml:
on_success:
- Rscript -e "covr::codecov()"Don't forget to add covr to the Suggests: field of your package's
DESCRIPTION file; possibly also to Remotes: for r-lib/covr.
For further details regarding Appveyor CI integration, also have a look at r-appveyor.
To use a different CI service or call codecov() locally you can set the
environment variable CODECOV_TOKEN to the token generated on codecov.io.
Codecov currently has support for the following CI systems (* denotes support
without needing CODECOV_TOKEN).
You will also need to enable the repository on Codecov.
Alternatively you can upload your results to Coveralls
using coveralls().
r_github_packages:
- r-lib/covr
after_success:
- Rscript -e 'covr::coveralls()'For CI systems not supported by coveralls you need to set the COVERALLS_TOKEN
environment variable. It is wise to use a Secure Variable
so that it is not revealed publicly.
Also you will need to turn on coveralls for your project at https://coveralls.io/repos.
covr supports a few of different ways of excluding some or all of a file.
A .covrignore file located in your package's root directory can be used to
exclude files or directories.
The lines in the .covrignore file are interpreted as a list of file globs to
ignore. It uses the globbing rules in Sys.glob(). Any directories listed will
ignore all the files in the directory.
Alternative locations for the file can be set by the environment variable
COVR_COVRIGNORE or the R option covr.covrignore.
The .covrignore file should be added to your .RBuildignore file unless you
want to distribute it with your package. If so it can be added to
inst/.covrignore instead.
The function_exclusions argument to package_coverage() can be used to
exclude functions by name. This argument takes a vector of regular expressions
matching functions to exclude.
# exclude print functions
package_coverage(function_exclusions = "print\\.")
# exclude `.onLoad` function
package_coverage(function_exclusions = "\\.onLoad")The line_exclusions argument to package_coverage() can be used to exclude some or
all of a file. This argument takes a list of filenames or named ranges to
exclude.
# exclude whole file of R/test.R
package_coverage(line_exclusions = "R/test.R")
# exclude lines 1 to 10 and 15 from R/test.R
package_coverage(line_exclusions = list("R/test.R" = c(1:10, 15)))
# exclude lines 1 to 10 from R/test.R, all of R/test2.R
package_coverage(line_exclusions = list("R/test.R" = c(1, 10), "R/test2.R"))In addition you can exclude lines from the coverage by putting special comments in your source code.
This can be done per line.
f1 <- function(x) {
x + 1 # nocov
}Or by specifying a range with a start and end.
f2 <- function(x) { # nocov start
x + 2
} # nocov endThe patterns used can be specified by setting the global options
covr.exclude_pattern, covr.exclude_start, covr.exclude_end.
NB: The same pattern applies to exclusions in the src folder, so skipped lines in, e.g., C code (where comments can start with //) should look like // # nocov.
Covr should be compatible with any testing package, it uses
tools::testInstalledPackage() to run your packages tests.
Covr now supports Intel's icc compiler, thanks to work contributed by Qin
Wang at Oracle.
Covr is known to work with clang versions 3.5+ and gcc version 4.2+.
If the appropriate gcov version is not on your path you can set the appropriate
location with the covr.gcov options. If you set this path to "" it will turn
off coverage of compiled code.
options(covr.gcov = "path/to/gcov")covr tracks test coverage by modifying a package's code to add tracking calls
to each call.
The vignette vignettes/how_it_works.Rmd contains a detailed explanation of the technique and the rationale behind it.
You can view the vignette from within R using
vignette("how_it_works", package = "covr")Because covr modifies the package code it is possible there are unknown edge cases where that modification affects the output. In addition when tracking coverage for compiled code covr compiles the package without optimization, which can modify behavior (usually due to package bugs which are masked with higher optimization levels).