Merge pull request #923 from r-lib/issue-922

if `=` is on newline within function call, move key to same line

Author: lorenzwalthert

NEWS.md

@@ -23,39 +23,47 @@
   `styler.ignore_stop` omit the `#` (#849).
 
 
-**Other changes**
+**Features**
 
 * {styler} can be ran via GitHub Actions using 
   `usethis::use_github_action("style")` (#914).
+* added guarantee that styled code is parsable (#892).
+* Developers can now create style guides with indention characters other than 
+  spaces (#916).
+
+**Documentation**
+
+* Add vignette on distributing style guide (#846, #861).
+* Fix argument name `filetype` in Example for `style_dir()` (#855).
+
+
+**Bug fixes**
 
-* `.onLoad()` method no longer broken with {cli} >= 3.1 (#893).
 * Piped function without brackets `substitute(x %>% y)` don't get `()` added
   anymore for one level deep (not more yet, see #889), as this can change 
   outcome of the code (#876).
-* rules that add tokens don't break stylerignore sequences anymore (#891).
+* `.onLoad()` method no longer broken with {cli} >= 3.1 (#893).
 * Function calls containing `+` should no longer give any error on styling when 
   there are comments and line breaks under certain circumstances (#905). 
-* Add vignette on distributing style guide (#846, #861).
+* rules that add tokens don't break stylerignore sequences anymore (#891).
 * Alignment detection respects stylerignore (#850).
 * `Warning: Unknown or uninitialised column:` was fixed (#885).
 * Unaligned expressions with quoted key (e.g. `c("x" = 2)`) are now correctly
   detected (#881).
 * function calls with unequal number of token on different lines are no longer 
   deemed aligned if there are arbitrary spaces around the tokens on the lines 
   with most tokens (#902).
+* if a line starts with `EQ_SUB` (`=`), the corresponding key is moved to that
+  line too (#923).
 * ensure a trailing blank line also if the input is cached (#867).
 * Preserve trailing blank line in roxygen examples to simplify concatenation of
   examples (#880).
-* added guarantee that styled code is parsable (#892).
 * `indenty_by` is now also respected when curly braces are added to an if
   statement by {styler} (#915).
 * An error is now thrown on styling if input unicode characters can't be 
   correctly parsed for Windows and R < 4.2 (#883).
-* Developers can now create style guides with indention characters other than 
-  spaces (#916).
 * styling of text does not error anymore when the R option `OutDec` is set to 
   a non-default value (#912).
-* Fix argument name `filetype` in Example for `style_dir()` (#855).
 
 
 **Infrastructure**

R/rules-line-breaks.R

@@ -119,6 +119,21 @@ set_line_break_around_comma_and_or <- function(pd, strict) {
 
   pd$lag_newlines[comma_with_line_break_that_can_be_removed_before] <- 0L
   pd$lag_newlines[lag(comma_with_line_break_that_can_be_removed_before)] <- 1L
+
+  comma_with_line_break_that_can_be_moved_two_tokens_left <- which(
+    (pd$token == "EQ_SUB") &
+      (pd$lag_newlines > 0) &
+      (pd$token_before != "COMMENT") &
+      (lag(pd$token) != "'['")
+  )
+
+  pd$lag_newlines[comma_with_line_break_that_can_be_moved_two_tokens_left] <- 0L
+  token_before <- map_int(
+    comma_with_line_break_that_can_be_moved_two_tokens_left,
+    previous_non_comment,
+    pd = pd
+  )
+  pd$lag_newlines[token_before] <- 1L
   pd
 }
 

tests/testthat/line_breaks_and_other/around-eq-sub-in.R

@@ -0,0 +1,27 @@
+c(x = 2)
+
+c(x =
+    2)
+
+c(
+  x = 2)
+
+c(x
+  = 2)
+
+c(x = 2, a
+  =
+    1)
+
+
+c(x = 2, a
+  = # stuff
+    1)
+
+
+c(b=4, x # comment
+  = 2)
+
+
+c(x =# comment
+  2, c=)

tests/testthat/line_breaks_and_other/around-eq-sub-out.R

@@ -0,0 +1,39 @@
+c(x = 2)
+
+c(
+  x =
+    2
+)
+
+c(
+  x = 2
+)
+
+c(
+  x = 2
+)
+
+c(
+  x = 2,
+  a =
+    1
+)
+
+
+c(
+  x = 2,
+  a = # stuff
+    1
+)
+
+
+c(
+  b = 4, x # comment
+  = 2
+)
+
+
+c(
+  x = # comment
+    2, c =
+  )

tests/testthat/test-line_breaks_and_other.R

@@ -62,3 +62,9 @@ test_that("drop redundant line breaks in assignments", {
     transformer = style_text, scope = I(c("line_breaks", "tokens"))
   ), NA)
 })
+
+test_that("line is correctly broken around = ", {
+  expect_warning(test_collection("line_breaks_and_other", "around-eq-sub",
+    transformer = style_text
+  ), NA)
+})