support the new pipe operator |> in R 4.1.0

DESCRIPTION

@@ -1,7 +1,7 @@
 Package: formatR
 Type: Package
 Title: Format R Code Automatically
-Version: 1.9.1
+Version: 1.9.2
 Authors@R: c(
     person("Yihui", "Xie", role = c("aut", "cre"), email = "xie@yihui.name", comment = c(ORCID = "0000-0003-0645-5666")),
     person("Ed", "Lee", role = "ctb"),

NEWS.md

@@ -1,5 +1,8 @@
 # CHANGES IN formatR VERSION 1.10
 
+## NEW FEATURES
+
+- Support the new pipe operator `|>` in R 4.1.0.
 
 # CHANGES IN formatR VERSION 1.9
 

R/tidy.R

@@ -129,6 +129,7 @@ deparse2 = function(expr, width, warn = getOption('formatR.width.warning', TRUE)
     d[[i]] <<- x
     x2 = grep(pat.comment, x, invert = TRUE, value = TRUE)  # don't check comments
     x2 = gsub(pat.infix, '\\1\\2\\3', x2)  # remove extra spaces in %>% operators
+    x2 = restore_pipe(x2)
     p[[i]] <<- x2[nchar(x2, type = 'width') > width]
     k[i] <<- length(p[[i]]) == 0
   }
@@ -169,6 +170,7 @@ tidy_block = function(
     x = deparse(e, width)
     x = reindent_lines(x, indent)
     if (brace.newline) x = move_leftbrace(x)
+    x = restore_pipe(x)
     # remove white spaces on blank lines
     x = gsub(blank.comment2, '', x)
     paste(x, collapse = '\n')

R/utils.R

@@ -71,12 +71,18 @@ mask_comments = function(x, width, keep.blank.line, wrap = TRUE, spaces) {
   }
   # break lines after some infix operators such as %>%
   d.text = gsub(paste0('^(%)(', infix_ops, ')(%)$'), paste0('\\1\\2', spaces, '\\3'), d.text)
+  # similarly break lines after |>; later restore %|>|>% to |> in unmask_source()
+  d.text[d.text == '|>'] = paste0('%', '|>|>', spaces, '%')
 
   unlist(lapply(split(d.text, d.line), paste, collapse = ' '), use.names = FALSE)
 }
 
 infix_ops = '[>$]|T>|<>'
 
+restore_pipe = function(x) {
+  gsub('%[|]>[|]> +%\\s*$', '|>', x)
+}
+
 # no blank lines before an 'else' statement!
 move_else = function(x) {
   blank = grepl('^\\s*$', x)

tests/testit/test-tidy.R

@@ -140,3 +140,7 @@ iris %>%
 assert('magrittr lines are wrapped after the pipes', {
   (paste(tidy.res(x1, indent = 2), collapse = '\n') %==% x2)
 })
+
+if (getRversion() >= '4.1.0') assert('The new pipe |> is supported', {
+  (tidy.res('1|>c()') %==% '1 |>\n    c()')
+})