The mock contexts in httptest can raise errors or messages when requests are made, and those (error) messages have three elements, separated by space: (1) the request method (e.g. "GET"); (2) the request URL; and (3) the request body, if present. These verb-expectation functions look for this message shape. expect_PUT, for instance, looks for a request message that starts with "PUT".

expect_GET(object, url = "", ...)

expect_POST(object, url = "", ...)

expect_PATCH(object, url = "", ...)

expect_PUT(object, url = "", ...)

expect_DELETE(object, url = "", ...)

expect_no_request(object, ...)



Code to execute that may cause an HTTP request


character: the URL you expect a request to be made to. Default is an empty string, meaning that you can just assert that a request is made with a certain method without asserting anything further.


character segments of a request payload you expect to be included in the request body, to be joined together by paste0. You may also pass any of the following named logical arguments, which will be passed to base::grepl():

  • fixed: Should matching take the pattern as is or treat it as a regular expression. Default: TRUE, and note that this default is the opposite of the default in grepl. (The rest of the arguments follow its defaults.)

  • Should matching be done case insensitively? Default: FALSE, meaning matches are case sensitive.

  • perl: Should Perl-compatible regular expressions be used? Default: FALSE

  • useBytes: Should matching be done byte-by-byte rather than character-by-character? Default: FALSE


A testthat 'expectation'.


library(httr) without_internet({ expect_GET(GET(""), "") expect_GET(GET(""), "[a-z]+", fixed=FALSE) # For regular expression matching expect_PUT(PUT("", body='{"a":1}'), '', '{"a":1}') expect_PUT(PUT("", body='{"a":1}')) expect_no_request(rnorm(5)) })
#> [1] -1.400043517 0.255317055 -2.437263611 -0.005571287 0.621552721