From aeba4b732bac70e0631476056fc981e2a5b73a9d Mon Sep 17 00:00:00 2001
From: kbvernon <kenneth.b.vernon@gmail.com>
Date: Wed, 18 Sep 2024 17:10:22 -0600
Subject: [PATCH 1/2] check for empty string

---
 R/use_crate.R | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/R/use_crate.R b/R/use_crate.R
index cea33920..c1fcbb04 100644
--- a/R/use_crate.R
+++ b/R/use_crate.R
@@ -64,7 +64,8 @@ use_crate <- function(
   )
 
   # clear empty options
-  cargo_add_opts <- purrr::discard(cargo_add_opts, rlang::is_empty)
+  is_null_or_empty_string <- function(x){ !nzchar(x) || rlang::is_empty(x) }
+  cargo_add_opts <- purrr::discard(cargo_add_opts, is_null_or_empty_string)
 
   # combine option names and values into single strings
   adtl_args <- unname(purrr::imap_chr(

From 9ae8f3a9363b66c5d580504cbf80b62db040744a Mon Sep 17 00:00:00 2001
From: kbvernon <kenneth.b.vernon@gmail.com>
Date: Sun, 22 Sep 2024 16:45:05 -0600
Subject: [PATCH 2/2] draft and test

---
 R/read_cargo_metadata.R                   | 44 +++++++++++++++++++++++
 tests/testthat/test-read_cargo_metadata.R | 14 ++++++++
 2 files changed, 58 insertions(+)
 create mode 100644 R/read_cargo_metadata.R
 create mode 100644 tests/testthat/test-read_cargo_metadata.R

diff --git a/R/read_cargo_metadata.R b/R/read_cargo_metadata.R
new file mode 100644
index 00000000..15fd0eac
--- /dev/null
+++ b/R/read_cargo_metadata.R
@@ -0,0 +1,44 @@
+#' Retrieve metadata for packages and workspaces
+#'
+#' @param path character scalar, the R package directory
+#'
+#' @details
+#' For more details, see
+#' \href{https://doc.rust-lang.org/cargo/commands/cargo-metadata.html}{Cargo docs}
+#' for `cargo-metadata`. See especially "JSON Format" to get a sense of what you
+#' can expect to find in the returned list.
+#'
+#' @return `list`, including the following elements:
+#' - "packages"
+#' - "workspace_members"
+#' - "workspace_default_members"
+#' - "resolve"
+#' - "target_directory"
+#' - "version"
+#' - "workspace_root"
+#' - "metadata"
+#'
+#' @export
+#'
+#' @examples
+#' \dontrun{
+#' read_cargo_metadata()
+#' }
+#'
+read_cargo_metadata <- function(path = ".") {
+  root <- rprojroot::find_package_root_file(path = path)
+
+  rust_folder <- normalizePath(
+    file.path(root, "src", "rust"),
+    winslash = "/",
+    mustWork = FALSE
+  )
+
+  out <- processx::run(
+    "cargo",
+    args = c("metadata", "--format-version=1", "--no-deps"),
+    wd = rust_folder
+  )
+
+  jsonlite::fromJSON(out[["stdout"]])
+}
diff --git a/tests/testthat/test-read_cargo_metadata.R b/tests/testthat/test-read_cargo_metadata.R
new file mode 100644
index 00000000..d92aaafd
--- /dev/null
+++ b/tests/testthat/test-read_cargo_metadata.R
@@ -0,0 +1,14 @@
+test_that("read_cargo_metadata() returns package or workspace metadata", {
+  skip_if_not_installed("usethis")
+
+  path <- local_package("testpkg")
+
+  # capture setup messages
+  withr::local_options(usethis.quiet = FALSE)
+
+  use_extendr(path, quiet = TRUE)
+
+  out <- read_cargo_metadata()
+
+  expect_s3_class(out, "list")
+})