cpp11 dynlib

[pachadotdev]

Hi @hadley

These minimal changes allow the user to just write functions of the form

#include <cpp11.hpp>

using namespace cpp11;

[[cpp11::register]] int hello(int x) {
    return x + 1;
}

Immediately after using use_cpp11().

With this change the user can run devtools::load_all() and hello(1) will work. Otherwise it says pkgname_hello not found.

Semi-related to r-lib/cpp11#341

[hadley]

I think it would be better to follow a similar process to use_import_from(), i.e. use roxygen_ns_append() to write to the package doc, and then run roxygen_update_ns() to automatically update the namespace and reload the package.

[pachadotdev]

I think it would be better to follow a similar process to use_import_from(), i.e. use roxygen_ns_append() to write to the package doc, and then run roxygen_update_ns() to automatically update the namespace and reload the package.

ready!
good suggestion, I just tried with usethis::create_package() and it works

[hadley]

Can you please also add a news bullet and a test? (Probably something in "use_cpp11() creates files/dirs, edits DESCRIPTION and .gitignore")

[pachadotdev]

@hadley it should be ok now

[hadley]

Thanks!

[jennybc]

I have reverted this because I need to release usethis under a CRAN deadline and CI has been failing ever since this PR was merged. This change creates a test-time dependency on cpp11 and decor, neither of which usethis has a direct or indirect dependency on. I've fiddled around with the failing tests a bit, but there's no easy way, e.g. via a simple mock, to patch this up quickly, because the dependencies are needed for the roxygenize() step which is precisely the point. So @pachadotdev or @hadley if you care a lot about this, we need to either give up on testing the feature or invest time in more refactoring and mocking.

── Error ('test-cpp11.R:19:3'): use_cpp11() creates files/dirs, edits DESCRIPTION and .gitignore ──
<packageNotFoundError/error/condition>
Error in `loadNamespace(x)`: there is no package called 'cpp11'
Backtrace:
     ▆
  1. ├─usethis::use_cpp11() at test-cpp11.R:19:3
  2. │ └─usethis:::roxygen_update_ns() at usethis/R/cpp11.R:31:3
  3. │   ├─utils::capture.output(...) at usethis/R/roxygen.R:105:3
  4. │   │ └─base::withVisible(...elt(i))
  5. │   ├─base::suppressMessages(roxygen2::roxygenise(proj_get(), "namespace")) at usethis/R/roxygen.R:105:3
  6. │   │ └─base::withCallingHandlers(...)
  7. │   └─roxygen2::roxygenise(proj_get(), "namespace") at usethis/R/roxygen.R:105:3
  8. │     └─roxygen2 (local) load_code(base_path)
  9. │       └─pkgload::load_all(path, helpers = FALSE, attach_testthat = FALSE)
 10. │         └─pkgbuild::compile_dll(path, quiet = quiet)
 11. │           └─pkgbuild:::update_registration(...)
 12. └─base::loadNamespace(x)
 13.   └─base::withRestarts(stop(cond), retry_loadNamespace = function() NULL)
 14.     └─base (local) withOneRestart(expr, restarts[[1L]])
 15.       └─base (local) doWithOneRestart(return(expr), restart)

[pachadotdev]

I have reverted this because I need to release usethis under a CRAN deadline and CI has been failing ever since this PR was merged. This change creates a test-time dependency on cpp11 and decor, neither of which usethis has a direct or indirect dependency on. I've fiddled around with the failing tests a bit, but there's no easy way, e.g. via a simple mock, to patch this up quickly, because the dependencies are needed for the roxygenize() step which is precisely the point. So @pachadotdev or @hadley if you care a lot about this, we need to either give up on testing the feature or invest time in more refactoring and mocking.

── Error ('test-cpp11.R:19:3'): use_cpp11() creates files/dirs, edits DESCRIPTION and .gitignore ──
<packageNotFoundError/error/condition>
Error in `loadNamespace(x)`: there is no package called 'cpp11'
Backtrace:
     ▆
  1. ├─usethis::use_cpp11() at test-cpp11.R:19:3
  2. │ └─usethis:::roxygen_update_ns() at usethis/R/cpp11.R:31:3
  3. │   ├─utils::capture.output(...) at usethis/R/roxygen.R:105:3
  4. │   │ └─base::withVisible(...elt(i))
  5. │   ├─base::suppressMessages(roxygen2::roxygenise(proj_get(), "namespace")) at usethis/R/roxygen.R:105:3
  6. │   │ └─base::withCallingHandlers(...)
  7. │   └─roxygen2::roxygenise(proj_get(), "namespace") at usethis/R/roxygen.R:105:3
  8. │     └─roxygen2 (local) load_code(base_path)
  9. │       └─pkgload::load_all(path, helpers = FALSE, attach_testthat = FALSE)
 10. │         └─pkgbuild::compile_dll(path, quiet = quiet)
 11. │           └─pkgbuild:::update_registration(...)
 12. └─base::loadNamespace(x)
 13.   └─base::withRestarts(stop(cond), retry_loadNamespace = function() NULL)
 14.     └─base (local) withOneRestart(expr, restarts[[1L]])
 15.       └─base (local) doWithOneRestart(return(expr), restart)

thanks for letting me know
i am on medical leave but i still check the phone, when i'm back i can try refactoring

[jennybc]

I suspect this should just be roxygen_ns_append(...) && roxygen_remind(), as done elsewhere in the package. Initiating use of cpp11 is a once-per-package event, so it's OK for it to involve a couple of steps.