lose styler dep

DESCRIPTION

@@ -1,6 +1,6 @@
 Package: certestyle
 Title: A Certe R Package for Applying Certe Organisational Style
-Version: 1.6.7
+Version: 1.6.8
 Authors@R: c(
   person(given = c("Matthijs", "S."), 
          family = "Berends",
@@ -25,7 +25,6 @@ Imports:
   purrr (>= 0.3.4),
   readr (>= 1.4.0),
   rstudioapi (>= 0.8),
-  styler (>= 1.3.2),
   viridisLite (>= 0.4.0),
   yaml (>= 2.2.0)
 Suggests: 
@@ -37,6 +36,7 @@ Suggests:
   knitr (>= 1.0.0),
   pillar (>= 1.5.0),
   rmarkdown,
+  styler (>= 1.3.2),
   testthat (>= 2.0.0),
   tibble (>= 3.0.0)
 License: GPL-2

NAMESPACE

@@ -80,6 +80,5 @@ importFrom(rstudioapi,convertTheme)
 importFrom(rstudioapi,getThemeInfo)
 importFrom(rstudioapi,getThemes)
 importFrom(rstudioapi,removeTheme)
-importFrom(styler,tidyverse_style)
 importFrom(viridisLite,viridis)
 importFrom(yaml,read_yaml)

R/styler.R

@@ -24,7 +24,7 @@
 #' `options(styler.addins_style_transformer = "certe_style_transformer()")`
 #' 
 #' Then use the keyboard shortcut of the `styler` package to apply the formatting.
-#' @param ... arguments passed on to [styler::tidyverse_style()]
+#' @param ... arguments passed on to `styler::tidyverse_style()`
 #' @details The Certe styler keeps the first argument of a function on the same line, puts all following arguments on a new line, and does not add another new line after the last argument. This makes these lines:
 #'
 #' ```
@@ -45,11 +45,13 @@
 #'         y.title = "Count",
 #'         title = "Count isolates per hospital/gender")
 #' ```
-#' @importFrom styler tidyverse_style
 #' @importFrom purrr some negate
 #' @export
 certe_style_transformer <- function(...) {
-  certe_style <- tidyverse_style(...)
+  if (!"styler" %in% rownames(utils::installed.packages())) {
+    stop("This requires the 'styler' package", call. = FALSE)
+  }
+  certe_style <- styler::tidyverse_style(...)
 
   # line breaks between *all* arguments if line breaks between *any*
   certe_style$line_break$set_linebreak_each_argument_if_multi_line <- function(pd) {

R/utils.R

@@ -62,4 +62,4 @@ s3_register <- function(generic, class, method = NULL) {
     registerS3method(generic, class, method_fn, envir = envir)
   }
   invisible()
-}
+}