feat: add use_extendr_badge()

NAMESPACE

@@ -23,6 +23,7 @@ export(rust_source)
 export(to_toml)
 export(use_crate)
 export(use_extendr)
+export(use_extendr_badge)
 export(use_msrv)
 export(use_positron)
 export(use_vscode)

NEWS.md

@@ -17,6 +17,7 @@
 * Adds [WebR](https://docs.r-wasm.org/webr/latest/) support out of the box for all extendr packages.
   * Note that not all Rust crates are wasm compatible. This change only enables the package to build in the `wasm32-unknown-emscripten` target. It does not guarantee all dependencies will compile.
 * Addresses new CRAN check in R 4.5+ adding warning for `_abort` usage
+* `use_extendr_badge()` has been added to add an extendr-specific badge to a `README.Rmd` via `usethis::use_badge()` <https://github.com/extendr/rextendr/pull/417>
 * Removes `Makevars.ucrt` as R versions < 4.1 are not supported by extendr <https://github.com/extendr/rextendr/pull/414> 
 * `purrr` has been replaced with [`R/standalone-purrr.R`](https://github.com/r-lib/rlang/blob/main/R/standalone-purrr.R) removing `purrr` from `Imports` <https://github.com/extendr/rextendr/pull/408>
 * `document()` will no longer try to save all open files using rstudioapi <https://github.com/extendr/rextendr/issues/404> <https://github.com/extendr/rextendr/issues/407>

R/badge.R

@@ -0,0 +1,35 @@
+#' extendr README badge
+#'
+#' Add the version of extendr being used by an R package to its README.
+#'
+#' Requires `usethis` to be available.
+#'
+#' @examples
+#' \dontrun{
+#' use_extendr_badge()
+#' }
+#'
+#' @inheritParams use_extendr
+#' @export
+use_extendr_badge <- function(path = ".") {
+  rlang::check_installed("usethis")
+  meta <- read_cargo_metadata(path)
+  deps <- meta[[c("packages", "dependencies")]][[1]]
+
+  if (rlang::is_null(deps)) {
+    cli::cli_abort("Unable to determine version of `extendr-api`")
+  }
+
+  is_extendr <- which(deps$name == "extendr-api")
+  if (!rlang::is_bare_numeric(is_extendr, 1)) {
+    cli::cli_abort("Unable to determine version of `extendr-api`")
+  }
+
+  extendr_version <- deps$req[is_extendr]
+
+  usethis::use_badge(
+    "extendr",
+    "https://extendr.github.io/extendr/extendr_api/",
+    sprintf("https://img.shields.io/badge/extendr-%s-276DC2", extendr_version)
+  )
+}

R/use_extendr.R

@@ -268,6 +268,10 @@ use_extendr <- function(
         "Please run {.fun rextendr::document} for changes to take effect."
       )
     )
+    # encourage use of use_extendr__badge
+    cli::cli_alert_info(
+      "Call {.fn use_extendr_badge} to add an extendr badge to your {.file README}"
+    )
   }
 
   return(invisible(TRUE))

_pkgdown.yml

@@ -33,3 +33,4 @@ reference:
   - make_module_macro
   - rust_sitrep
   - read_cargo_metadata
+  - use_extendr_badge

tests/testthat/_snaps/cran-compliance.md

@@ -20,7 +20,7 @@
       3 extendr-macros   *.*.*
       4      once_cell  *.*.*
       5          paste  *.*.*
-      6    proc-macro2  *.*.*
+      6    proc-macro2 *.*.*
       7          quote  *.*.*
       8            syn *.*.*
       9  unicode-ident  *.*.*

tests/testthat/_snaps/use_extendr.md

@@ -370,6 +370,7 @@
       > File 'configure.win' already exists. Skip writing the file.
       v Finished configuring extendr for package testpkg.wrap.
       * Please run `rextendr::document()` for changes to take effect.
+      i Call `use_extendr_badge()` to add an extendr badge to your 'README'
 
 # use_extendr() can overwrite files in non-interactive sessions
 
@@ -390,6 +391,7 @@
       v Writing 'configure.win'
       v Finished configuring extendr for package testpkg.
       * Please run `rextendr::document()` for changes to take effect.
+      i Call `use_extendr_badge()` to add an extendr badge to your 'README'
 
 ---