Error if `get_namespace()` fails by DavisVaughan · Pull Request #396 · r-lib/cpp11 · GitHub

Closes #317

Previously, this would hang indefinitely

cpp11::cpp_function('
SEXP test() {
  auto fn = cpp11::package("foo")["bar"];
  return fn();
}
')

test()
#> Error: object 'foo' not found

Now it at least says foo is not found, the same error that any other environment lookup failure would throw

Rather than hanging indefinitely when a function is called

I am confident about this switch:

r_env_get() uses Rf_findVarInFrame3(env, sym, TRUE) on older R
Rf_findVarInFrame() is exactly a wrapper around Rf_findVarInFrame3(env, sym, TRUE)

So r_env_get() is basically Rf_findVarInFrame() with a few extra checks - like erroring if the object is not found, as we want here.

On newer R it is using the "blessed" R_getVar() with inherits = false, which is also what we want.

Error if get_namespace() fails

4d37e95

Rather than hanging indefinitely when a function is called

DavisVaughan commented Aug 26, 2024

View reviewed changes

DavisVaughan merged commit 580c8de into r-lib:main Aug 26, 2024

DavisVaughan deleted the fix/package-error branch August 26, 2024 18:53

Error if get_namespace() fails - #396

                   }
                   sexp name_sexp = safe[Rf_install](name);
-                  return safe[Rf_findVarInFrame](R_NamespaceRegistry, name_sexp);
+                  return safe[detail::r_env_get](R_NamespaceRegistry, name_sexp);