Test package warning classes — expect_pkg_warning

When you use pkg_warn() to signal warnings, you can use this function to test that those warnings are generated as expected.

Usage

expect_pkg_warning_classes(object, package, ...)

Arguments

object: An expression that is expected to throw a warning.
package: (length-1 character) The name of the package to use in classes.
...: (character) Components of the class name, from least-specific to most.

Value

The warning condition invisibly. Assignments made inside object (e.g. result <- fn_that_warns()) are visible to the caller after this function returns. Unlike most testthat expectations, this expectation cannot be usefully chained.

Examples

expect_pkg_warning_classes(
  pkg_warn("stbl", "This is a test warning", "test_subclass"),
  "stbl",
  "test_subclass"
)
try(
  expect_pkg_warning_classes(
    pkg_warn("stbl", "This is a test warning", "test_subclass"),
    "stbl",
    "different_subclass"
  )
)
#> Error : Expected `captured` to have class "stbl-warning-different_subclass"/"stbl-warning"/"stbl-condition"/"rlang_warning"/"warning"/"condition".
#> Actual class: "stbl-warning-test_subclass"/"stbl-warning"/"stbl-condition"/"rlang_warning"/"warning"/"condition".