Automatically add needed cpp11 namespace directive (#1921)

Co-authored-by: Hadley Wickham <[email protected]>

.Rbuildignore

@@ -24,3 +24,4 @@
 ^internal$
 ^revdep-cloud$
 ^CRAN-SUBMISSION$
+^\.vscode$

NEWS.md

@@ -1,5 +1,7 @@
 # usethis (development version)
 
+* `use_cpp11()` now automatically updates the `NAMESPACE` (@pachadotdev, #1921).
+
 # usethis 2.2.2
 
 * Implicit usage of `numeric_version()` via comparison now always provides

R/cpp11.R

@@ -12,6 +12,7 @@ use_cpp11 <- function() {
   check_installed("cpp11")
   check_is_package("use_cpp11()")
   check_uses_roxygen("use_cpp11()")
+  check_has_package_doc("use_cpp11()")
   use_src()
 
   use_dependency("cpp11", "LinkingTo")
@@ -24,6 +25,11 @@ use_cpp11 <- function() {
 
   check_cpp_register_deps()
 
+  roxygen_ns_append(
+    sprintf("@useDynLib %s, .registration = TRUE", project_name())
+  )
+  roxygen_update_ns()
+
   invisible()
 }
 

tests/testthat/test-cpp11.R

@@ -7,10 +7,14 @@ test_that("use_cpp11() requires a package", {
 test_that("use_cpp11() creates files/dirs, edits DESCRIPTION and .gitignore", {
   create_local_package()
   use_roxygen_md()
+  use_package_doc()
 
   local_interactive(FALSE)
   local_check_installed()
-  local_mocked_bindings(check_cpp_register_deps = function() invisible())
+  local_mocked_bindings(
+    check_cpp_register_deps = function() invisible()
+    # project_name = function() "testpkg"
+  )
 
   use_cpp11()
 
@@ -21,6 +25,9 @@ test_that("use_cpp11() creates files/dirs, edits DESCRIPTION and .gitignore", {
 
   ignores <- read_utf8(proj_path("src", ".gitignore"))
   expect_true(all(c("*.o", "*.so", "*.dll") %in% ignores))
+
+  namespace <- read_utf8(proj_path("NAMESPACE"))
+  expect_true(any(grepl("useDynLib", namespace)))
 })
 
 test_that("check_cpp_register_deps is silent if all installed, emits todo if not", {