Use desc package to avoid mangling DESCRIPTION

Fixes #430

DESCRIPTION

@@ -11,25 +11,26 @@ Authors@R: c(
     person("Manuel", "Eugster", role = c("aut", "cph")),
     person("RStudio", role = "cph")
     )
-Depends:
+Depends: 
     R (>= 3.0.2)
-Imports:
+Imports: 
     stringr (>= 0.5),
     stringi,
     brew,
     digest,
     methods,
     Rcpp (>= 0.11.0),
-    R6
-Suggests:
+    R6,
+    desc
+Suggests: 
     testthat (>= 0.8.0),
     knitr,
     devtools,
     rmarkdown,
     covr
 VignetteBuilder: knitr
 LinkingTo: Rcpp
-Collate:
+Collate: 
     'RcppExports.R'
     'RdTopic.R'
     'alias.R'

NEWS.md

@@ -1,5 +1,8 @@
 # roxygen2 5.0.1.9000
 
+* Changes to DESCRIPTION (i.e. `Collate:` and `RoxygenNote`) now use
+  the desc package. This will minimise spurious changes (#430).
+
 * `@family` see also are added in the same order they appear, not 
   alphabetically (#315).
 

R/roclet-collate.R

@@ -37,19 +37,18 @@ register_tags(
 #' }
 #' @export
 update_collate <- function(base_path) {
-  collate <- generate_collate(file.path(base_path, "R"))
-  if (is.null(collate)) return()
+  new <- generate_collate(file.path(base_path, "R"))
+  if (is.null(new)) return()
 
   desc_path <- file.path(base_path, "DESCRIPTION")
-  old <- read.description(desc_path)
-
-  new <- old
-  new$Collate <- paste0("'", collate, "'", collapse = "\n")
+  old <- desc::desc_get_collate(file = desc_path)
 
   if (!identical(old, new)) {
     cat('Updating collate directive in ', desc_path, "\n")
-    write.description(new, desc_path)
+    desc::desc_set_collate(new, file = desc_path)
   }
+
+  invisible()
 }
 
 generate_collate <- function(base_path) {

R/safety.R

@@ -38,13 +38,12 @@ made_by <- function(comment) {
 
 update_roxygen_version <- function(base_path) {
   desc_path <- file.path(base_path, "DESCRIPTION")
-  old <- read.description(desc_path)
 
-  new <- old
-  new$RoxygenNote <- as.character(utils::packageVersion("roxygen2"))
+  new <- as.character(utils::packageVersion("roxygen2"))
+  old <- desc::desc_get("RoxygenNote", file = desc_path)[[1]]
 
   if (!identical(old, new)) {
     cat('Updating roxygen version in ', desc_path, "\n")
-    write.description(new, desc_path)
+    desc::desc_set(RoxygenNote = new, file = desc_path)
   }
 }