Add verbosity resetters

Closes #1414

NAMESPACE

@@ -482,6 +482,8 @@ export(quos_auto_name)
 export(raw_deparse_str)
 export(rep_along)
 export(rep_named)
+export(reset_message_verbosity)
+export(reset_warning_verbosity)
 export(return_from)
 export(run_on_load)
 export(scoped_bindings)

NEWS.md

@@ -1,5 +1,10 @@
 # rlang (development version)
 
+* New `reset_warning_verbosity()` and `reset_message_verbosity()`
+  functions. These reset the verbosity of messages signalled with
+  `warn()` and `inform()` with the `.frequency` argument. This is
+  useful for testing verbosity in your package (#1414).
+
 * Error messages now mention indexed calls like `foo$bar()`.
 
 * New `env_coalesce()` function to copy bindings from one environment

R/cnd-signal.R

@@ -355,6 +355,32 @@ peek_verbosity <- function(opt, call = caller_env()) {
   )
 }
 
+#' @rdname abort
+#' @param id The identifying string of the condition that was supplied
+#'   as `.frequency_id` to `warn()` or `inform()`.
+#' @export
+reset_warning_verbosity <- function(id) {
+  reset_verbosity(id, "warning")
+}
+#' @rdname abort
+#' @export
+reset_message_verbosity <- function(id) {
+  reset_verbosity(id, "message")
+}
+reset_verbosity <- function(id, type = c("message", "warning")) {
+  check_string(id)
+  type <- arg_match(type)
+
+  env <- switch(
+    type,
+    message = message_freq_env,
+    warning = warning_freq_env
+  )
+  env[[id]] <- NULL
+
+  invisible(NULL)
+}
+
 message_freq <- function(message, frequency, type) {
   if (is_string(frequency, "always")) {
     return(chr())

tests/testthat/test-cnd-signal.R

@@ -299,6 +299,23 @@ test_that("cnd_signal() sets call", {
   expect_equal(cnd$call, quote(f()))
 })
 
+test_that("can reset verbosity", {
+  on.exit(reset_warning_verbosity("test_reset_verbosity"))
+
+  expect_warning(
+    warn("foo", .frequency = "once", .frequency_id = "test_reset_verbosity")
+  )
+  expect_no_warning(
+    warn("foo", .frequency = "once", .frequency_id = "test_reset_verbosity")
+  )
+
+  reset_warning_verbosity("test_reset_verbosity")
+
+  expect_warning(
+    warn("foo", .frequency = "once", .frequency_id = "test_reset_verbosity")
+  )
+})
+
 
 # Lifecycle ----------------------------------------------------------