check in linter

Author: MichaelChirico

.ci/linters/rd/backtick_linter.R

@@ -0,0 +1,22 @@
+# ensure no markdown-style backticks wind up in Rd where \code is intended
+options_documentation_linter = function(rd_file) {
+  rd = tools::parse_Rd(rd_file)
+
+  error_if_backtick = function(rd_obj) {
+    if (!is.recursive(rd_obj)) {
+      if (any(grepl("`", rd_obj, fixed=TRUE))) {
+        stop(sprintf(
+          "Rd is not markdown -- backticks (`) don't render as code! Use \\code{...}.\nObserved in string '%s' in file %s",
+          trimws(rd_obj), rd_file
+        ))
+      }
+      return(invisible())
+    }
+    tags = vapply(rd_obj, \(x) attr(x, "Rd_tag") %||% "", FUN.VALUE="")
+     # backtick is valid inside R code (e.g. \examples, \code, \preformatted)
+    rd_obj = rd_obj[!tags %in% c("RCODE", "VERB")]
+    lapply(rd_obj, error_if_backtick)
+  }
+
+  invisible(error_if_backtick(rd))
+}