show_news(): Support NEWS in Rd and md formats and under inst (#2551)

Mirrors the search path documented in utils::news() for NEWS files. Uses
the internal machinery of tools to build news databases.

---------

Co-authored-by: Hadley Wickham <h.wickham@gmail.com>

Author: arcresu

NEWS.md

@@ -4,6 +4,7 @@
 * New `check_mac_devel()` function to check a package using the macOS builder at https://mac.r-project.org/macbuilder/submit.html (@nfrerebeau, #2507)
 * `is_loading()` is now re-exported from pkgload (#2556).
 * `load_all()` now errors if called recursively, i.e. if you accidentally include a `load_all()` call in one of your R source files (#2617).
+* `show_news()` now looks for NEWS files in the same locations as `utils::news()`: `inst/NEWS.Rd`, `NEWS.md`, `NEWS`, and `inst/NEWS` (@arcresu, #2499).
 
 # devtools 2.4.6
 

R/show-news.R

@@ -7,18 +7,25 @@
 #' @export
 show_news <- function(pkg = ".", latest = TRUE, ...) {
   pkg <- as.package(pkg)
-  news_path <- path(pkg$path, "NEWS")
+  news_path <- find_news(pkg$path)
 
-  if (!file_exists(news_path)) {
-    cli::cli_abort("No NEWS found")
-  }
+  withCallingHandlers(
+    {
+      news_db <- switch(
+        path_ext(news_path),
+        Rd = ("tools" %:::% ".build_news_db_from_package_NEWS_Rd")(news_path),
+        md = ("tools" %:::% ".build_news_db_from_package_NEWS_md")(news_path),
+        ("tools" %:::% ".news_reader_default")(news_path)
+      )
+    },
+    error = function(e) {
+      cli::cli_abort("Failed to parse NEWS file.", parent = e)
+    }
+  )
 
   check_dots_used(action = getOption("devtools.ellipsis_action", rlang::warn))
 
-  out <- utils::news(
-    ...,
-    db = ("tools" %:::% ".news_reader_default")(news_path)
-  )
+  out <- utils::news(..., db = news_db)
   if (latest) {
     ver <- numeric_version(out$Version)
     recent <- ver == max(ver)
@@ -27,3 +34,19 @@ show_news <- function(pkg = ".", latest = TRUE, ...) {
     out
   }
 }
+
+find_news <- function(path) {
+  news_paths <- c(
+    file.path(path, "inst", "NEWS.Rd"),
+    file.path(path, "NEWS.md"),
+    file.path(path, "NEWS"),
+    file.path(path, "inst", "NEWS")
+  )
+  news_path <- news_paths[file_exists(news_paths)]
+
+  if (length(news_path) == 0) {
+    cli::cli_abort("Failed to find NEWS file.")
+  }
+
+  path_abs(news_path[[1]])
+}

tests/testthat/_snaps/show-news.md

@@ -0,0 +1,18 @@
+# fails when NEWS is missing or improperly formatted
+
+    Code
+      show_news(pkg)
+    Condition
+      Error in `find_news()`:
+      ! Failed to find NEWS file.
+
+---
+
+    Code
+      show_news(pkg)
+    Condition
+      Error in `show_news()`:
+      ! Failed to parse NEWS file.
+      Caused by error:
+      ! NEWS.Rd: Sections \title, and \name must exist and be unique in Rd files
+

tests/testthat/test-show-news.R

@@ -0,0 +1,29 @@
+test_that("find_news() finds NEWS in all expected locations", {
+  pkg <- local_package_create()
+
+  dir_create(pkg, "inst")
+  file_create(pkg, "inst", "NEWS")
+  expect_equal(path_rel(find_news(pkg), pkg), path("inst/NEWS"))
+
+  file_create(pkg, "NEWS")
+  expect_equal(path_rel(find_news(pkg), pkg), path("NEWS"))
+
+  file_create(pkg, "NEWS.md")
+  expect_equal(path_rel(find_news(pkg), pkg), path("NEWS.md"))
+
+  file_create(pkg, "inst", "NEWS.Rd")
+  expect_equal(path_rel(find_news(pkg), pkg), path("inst/NEWS.Rd"))
+})
+
+test_that("fails when NEWS is missing or improperly formatted", {
+  skip_on_cran()
+  skip_unless_r(">= 4.2.0") # different error message
+
+  pkg <- local_package_create()
+  expect_snapshot(show_news(pkg), error = TRUE)
+
+  dir_create(pkg, "inst")
+  file_create(pkg, "inst", "NEWS.Rd")
+
+  expect_snapshot(show_news(pkg), error = TRUE)
+})