Merge pull request #876 from lorenzwalthert/issue-873

- Don't add `()` within substitute piped calls (#873).

NEWS.md

@@ -1,5 +1,7 @@
 # styler 1.6.2.9000 (Development version)
 
+* Piped function without brackets `substitute(x %>% y)` don't get `()` added
+  anymore, as this can change outcome of the code (#876).
 * Alignment detection respects stylerignore (#850).
 * Add vignette on distributing style guide (#846, #861).
 * Enable pre-commit.ci (#843).

R/rules-tokens.R

@@ -17,6 +17,13 @@ resolve_semicolon <- function(pd) {
 }
 
 add_brackets_in_pipe <- function(pd) {
+  if (!identical(pd$text[next_non_comment(pd, 0L)], "substitute")) {
+    pd$child <- map(pd$child, add_brackets_in_pipe_child)
+  }
+  pd
+}
+
+add_brackets_in_pipe_child <- function(pd) {
   is_pipe <- pd$token %in% c("SPECIAL-PIPE", "PIPE")
   Reduce(add_brackets_in_pipe_one, which(is_pipe), init = pd)
 }

tests/testthat/test-token_adding_removing.R

@@ -43,3 +43,9 @@ test_that("No braces are added if conditional statement is within pipe", {
     transformer = style_text
   ), NA)
 })
+
+test_that("No brace is added within `substitute()`", {
+  expect_warning(test_collection("token_adding_removing", "substitute",
+    transformer = style_text
+  ), NA)
+})

tests/testthat/token_adding_removing/substitute-in.R

@@ -0,0 +1,3 @@
+expr <- substitute(airquality %>% FUN_EXPR, env = list(FUN_EXPR = call("FUN_head")))
+a %>%
+  x

tests/testthat/token_adding_removing/substitute-out.R

@@ -0,0 +1,3 @@
+expr <- substitute(airquality %>% FUN_EXPR, env = list(FUN_EXPR = call("FUN_head")))
+a %>%
+  x()