fix: update extract meta to work with new default feature in upstream (#483)

* update extract meta to work with new default feature in upstream

* fix lint and add sccache to gha

* reverst sccache changes

Author: JosiahParry

.github/workflows/R-CMD-check.yaml

@@ -44,6 +44,13 @@ jobs:
           toolchain: ${{ matrix.config.rust-version }}
           targets: ${{ matrix.config.rust-target }}
 
+      # Add rust-cache for faster builds
+      - name: Cache Rust dependencies
+        uses: Swatinem/rust-cache@v2
+        with:
+          shared-key: ${{ matrix.config.os }}-${{ matrix.config.rust-version }}
+          cache-on-failure: true
+
       - uses: baptiste0928/cargo-install@v3
         if: matrix.config.r == 'release'
         with:

R/find_exports.R

@@ -5,7 +5,11 @@ find_exports <- function(clean_lns) {
 
   # start and end may empty
   if (rlang::is_empty(start) || rlang::is_empty(end)) {
-    return(data.frame(name = character(0), type = character(0), lifetime = character(0)))
+    return(data.frame(
+      name = character(0),
+      type = character(0),
+      lifetime = character(0)
+    ))
   }
 
   map2(start, end, \(.x, .y) extract_meta(clean_lns[.x:.y])) |>
@@ -16,8 +20,9 @@ find_exports <- function(clean_lns) {
 }
 
 # Finds lines which contain #[extendr] (allowing additional spaces)
+# Excludes #[extendr(default=...)] which is used for function arguments
 find_extendr_attrs_ids <- function(lns) {
-  which(stringi::stri_detect_regex(lns, r"{#\s*\[\s*extendr(\s*\(.*\))?\s*\]}"))
+  which(stringi::stri_detect_regex(lns, r"{#\s*\[\s*extendr(\s*\((?!.*default\s*=).*\))?\s*\]}"))
 }
 
 # Gets function/module metadata from a subset of lines.
@@ -29,7 +34,15 @@ extract_meta <- function(lns) {
     "(?:(?<struct>struct)|(?<enum>enum)|(?<fn>fn)|(?<impl>impl)(?:\\s*<(?<lifetime>.+?)>)?)\\s+(?<name>(?:r#)?(?:_\\w+|[A-z]\\w*))" # nolint: line_length_linter
   ) |>
     as.data.frame() |>
-    rlang::set_names(c("match", "struct", "enum", "fn", "impl", "lifetime", "name")) |>
+    rlang::set_names(c(
+      "match",
+      "struct",
+      "enum",
+      "fn",
+      "impl",
+      "lifetime",
+      "name"
+    )) |>
     dplyr::filter(!is.na(.data$match))
 
   # If no matches have been found, then the attribute is misplaced
@@ -38,10 +51,10 @@ extract_meta <- function(lns) {
     # meaningful output or source line numbers.
     code_sample <- stringi::stri_sub(
       glue_collapse(lns, sep = "\n  "),
-      1, 80
+      1,
+      80
     )
 
-
     rlang::abort(
       cli::cli_fmt({
         cli::cli_text(

tests/data/test-default-arg.Rmd

@@ -0,0 +1,15 @@
+
+```{r, include = FALSE}
+library(rextendr)
+```
+
+
+```{extendrsrc engine.opts = list(use_dev_extendr=TRUE)}
+#[extendr]
+fn check_default(#[extendr(default = "NULL")] x: Robj) ->  bool {
+  x.is_null()
+}
+```
+```{r}
+testthat::expect_true(check_default())
+```

tests/testthat/test-knitr-engine.R

@@ -34,3 +34,15 @@ test_that("Snapshot test of knitr-engine", {
   knitr::knit(input, output)
   expect_snapshot(cat_file(output))
 })
+
+
+test_that("knitr-engine for #[extendr(default = )]", {
+  skip_if_cargo_unavailable()
+  skip_if_not_installed("knitr")
+  skip_on_cran()
+
+  input <- file.path("../data/test-default-arg.Rmd")
+  output <- withr::local_file("snapshot-extendr-default.md")
+  knitr::knit(input, output)
+  expect_true(check_default())
+})