R: What is the working directory when executing covr?

Question

I'm working on a project, where I load a json file. By default, I start the project at the root of the project, however when testing, the path changes. Therefore I included the following statement:

if (grepl("testthat", getwd())) {
    template <- jsonlite::read_json("../../templates/initial_status.json")
  }else{
    template <- jsonlite::read_json("./templates/initial_status.json")
  }

This works, however, when using covr::gitlab() the file cannot be opened. I guess the working directory changed and therefore the file is not found:

Error in `open.connection(con, "rb")`: kann Verbindung nicht öffnen
Backtrace:
    x
 1. \-MyPackage::api_create(...) at test-API.R:40:2
 2.   \-MyPackage:::get_initial_status(initial_status)
 3.     \-jsonlite::read_json("../../templates/initial_status.json")

Of course a working around is to use setwd(...) however I don't like this, because I want to publish the package and therefore user may place the package in different locations.

What's the best solution here?

Answer 1

It seems to execute from a random temporary directory like this: "/private/var/folders/wr/_qxy_jbd2kg1t72cr7d89_jc0000gn/T/RtmptlUqd8/R_LIBS171fb7c114d3c/pkg_name/pkg_name-tests/testthat"

I stumbled upon this because it quite un-intuitively makes tests fail which do not fail in context if they rely on something with a path (e.g. a call to load in global variables from a file, etc.)

I just tried this by adding a test like:

test_that("working_dir", {expect_identical(getwd(), "working_dir")})

and upon running covr::package_coverage() got:

══ Failed tests ════════════════════════════════════════════════════════════════
── Failure ('test-stuff.R:18:20'): working_dir ────────────────────────────────────────
getwd() (`actual`) not identical to "working_dir" (`expected`).

actual vs expected
- "/private/var/folders/wr/_qxy_jbd2kg1t72cr7d89_jc0000gn/T/RtmptlUqd8/R_LIBS171fb7c114d3c/pkg_name/pkg_name-tests/testthat"
+ "working_dir"

Echoing here::here() instead will return something like /private/var/folders/wr/_qxy_jbd2kg1t72cr7d89_jc0000gn/T/RtmptlUqd8/R_LIBS171fb7c114d3c/pkg_name so I assume it copies the package directory in entirety somewhere and maybe it can help you.

Unfortunately it doesn't help at all if you rely on resources in a folder above your package folder.