vcapply <- function(X, FUN, ..., USE.NAMES = TRUE) {
  vapply(
    X = X,
    FUN = FUN,
    FUN.VALUE = character(1L),
    ...,
    USE.NAMES = USE.NAMES
  )
}

astyle <- function(extra_args = character()) {
  astyle_cmd <- "astyle"
  if (Sys.which(astyle_cmd) == "") {
    testthat::skip("astyle not found")
  }

  astyle_args <- c(
    "-n",
    "--indent=spaces=2",
    "--indent-namespaces",
    "--indent-preproc-block",
    "--unpad-paren",
    "--pad-header",
    "--min-conditional-indent=0",
    "--align-pointer=type",
    "--align-reference=type"
  )

  src_path <- normalizePath(vcapply(
    c("../../src", "../../inst/include"),
    testthat::test_path
  ))
  src_files <- dir(
    src_path,
    "[.](?:cpp|h)$",
    recursive = TRUE,
    full.names = TRUE
  )
  astyle_files <- grep(
    "(?:RcppExports[.]cpp|static_assert[.]h)",
    src_files,
    value = TRUE,
    invert = TRUE
  )
  output <- system2(
    astyle_cmd,
    c(astyle_args, astyle_files, extra_args),
    stdout = TRUE,
    stderr = TRUE
  )
  unchanged <- grepl("^Unchanged", output)
  if (any(!unchanged)) {
    warning(paste(output[!unchanged], collapse = "\n"))
  }
}