tolerate empty lines at start of news file

NEWS.md

@@ -13,6 +13,9 @@
   usethis no longer uses the `ui_*()` functions internally, in favor of new
   cli-based helpers that are not exported.
 
+* `usethis::use_version()` now tolerates empty / blank lines preceding the
+  first section title in the package NEWS file. (#1976)
+
 # usethis 2.2.3
 
 * Patch release with changes to `.Rd` files requested by CRAN.

R/news.R

@@ -40,15 +40,25 @@ use_news_heading <- function(version) {
   }
 
   news <- read_utf8(news_path)
-  title <- glue("# {project_name()} {version}")
+  if (length(news) == 0) {
+    return(news)
+  }
 
-  if (title == news[[1]]) {
+  # find first non-blank line in news
+  for (idx in seq_along(news)) {
+    if (grepl("[^[:space:]]", news[[idx]])) {
+      break
+    }
+  }
+
+  title <- glue("# {project_name()} {version}")
+  if (title == news[[idx]]) {
     return(invisible())
   }
 
   development_title <- glue("# {project_name()} (development version)")
-  if (development_title == news[[1]]) {
-    news[[1]] <- title
+  if (development_title == news[[idx]]) {
+    news[[idx]] <- title
 
     ui_bullets(c("v" = "Replacing development heading in {.path NEWS.md}."))
     return(write_utf8(news_path, news))

tests/testthat/test-news.R

@@ -32,3 +32,16 @@ test_that("use_news_md() sets version number when 'production version'", {
   expect_snapshot(writeLines(read_utf8(proj_path("NEWS.md"))),
                   transform = scrub_testpkg)
 })
+
+test_that("use_news_heading() tolerates blank lines at start", {
+  create_local_package()
+
+  header <- sprintf("# %s (development version)", project_name())
+  writeLines(c("", header, "", "* Fixed the bugs."), con = "NEWS.md")
+
+  use_news_heading(version = "1.0.0")
+  contents <- read_utf8("NEWS.md")
+
+  expected <- sprintf("# %s 1.0.0", project_name())
+  expect_equal(contents[[2L]], expected)
+})