This expectation checks that a HTTP header (and potentially header value)
is present in a request. It works by inspecting the request object and
raising warnings that are caught by testthat::expect_warning().
expect_header(..., ignore.case = TRUE)NULL, according to expect_warning.
expect_header works both in the mock HTTP contexts and on "live" HTTP
requests.
library(httr)
with_fake_http({
expect_header(
GET("http://example.com", config = add_headers(Accept = "image/png")),
"Accept: image/png"
)
})
#> GET http://example.com
#> <simpleWarning: Accept: image/png>