From f0f28244ce8aa6ea4fffc08c7f9e688b4a8daeb9 Mon Sep 17 00:00:00 2001
From: Hadley Wickham <h.wickham@gmail.com>
Date: Mon, 20 May 2024 14:55:39 -0400
Subject: [PATCH] Message when reading/writing home page (#2544)

---
 NEWS.md                                   |  1 +
 R/build-home-index.R                      |  9 +++++++++
 tests/testthat/_snaps/build-home-index.md | 12 ++++++++++++
 tests/testthat/test-build-home-index.R    | 13 +++++++++++--
 4 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/NEWS.md b/NEWS.md
index 43dd3b98d..6715d2320 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,5 +1,6 @@
 # pkgdown (development version)
 
+* `build_home_index()` now reports when rendering the home page (#2544).
 * Bootstrap 3 has been deprecated. It was superseded in December 2021, and now we're starting to more directly encourage folks to move away from it.
 * Improve HTML5 compliance (#2369):
   * No longer support IE9 or earlier
diff --git a/R/build-home-index.R b/R/build-home-index.R
index 2a75c9d9f..3ed407bdb 100644
--- a/R/build-home-index.R
+++ b/R/build-home-index.R
@@ -8,11 +8,15 @@ build_home_index <- function(pkg = ".", quiet = TRUE) {
   data <- data_home(pkg)
 
   if (is.null(src_path)) {
+    cli::cli_inform("Reading {.file DESCRIPTION}")
     data$index <- linkify(pkg$desc$get_field("Description", ""))
   } else {
+    cli::cli_inform("Reading {src_path(path_rel(src_path, pkg$src_path))}")
     local_options_link(pkg, depth = 0L)
     data$index <- markdown_body(src_path)
   }
+
+  cur_digest <- file_digest(dst_path)
   render_page(pkg, "home", data, "index.html", quiet = quiet)
 
   strip_header <- isTRUE(pkg$meta$home$strip_header)
@@ -28,6 +32,11 @@ build_home_index <- function(pkg = ".", quiet = TRUE) {
     logo = logo_path(pkg, depth = 0)
   )
 
+  new_digest <- file_digest(dst_path)
+  if (cur_digest != new_digest) {
+    writing_file(path_rel(dst_path, pkg$dst_path), "index.html")
+  }
+
   invisible()
 }
 
diff --git a/tests/testthat/_snaps/build-home-index.md b/tests/testthat/_snaps/build-home-index.md
index 833f84e7a..510a7c5b3 100644
--- a/tests/testthat/_snaps/build-home-index.md
+++ b/tests/testthat/_snaps/build-home-index.md
@@ -1,3 +1,15 @@
+# messages about reading and writing
+
+    Code
+      build_home_index(pkg)
+    Message
+      Reading 'DESCRIPTION'
+      Writing `index.html`
+    Code
+      build_home_index(pkg)
+    Message
+      Reading 'DESCRIPTION'
+
 # data_home_sidebar() works by default
 
     Code
diff --git a/tests/testthat/test-build-home-index.R b/tests/testthat/test-build-home-index.R
index 858e8b556..3fc5f6808 100644
--- a/tests/testthat/test-build-home-index.R
+++ b/tests/testthat/test-build-home-index.R
@@ -1,3 +1,12 @@
+test_that("messages about reading and writing", {
+  pkg <- local_pkgdown_site(test_path("assets/home-index-rmd"))
+
+  expect_snapshot({
+    build_home_index(pkg)
+    build_home_index(pkg)
+  })
+})
+
 test_that("title and description come from DESCRIPTION by default", {
   pkg <- as_pkgdown(test_path("assets/home-index-rmd"))
   expect_equal(data_home(pkg)$pagetitle, "A test package")
@@ -24,7 +33,7 @@ test_that("version formatting in preserved", {
   expect_equal(pkg$version, "1.0.0-9000")
 
   suppressMessages(init_site(pkg))
-  build_home_index(pkg, quiet = TRUE)
+  suppressMessages(build_home_index(pkg))
   index <- read_lines(path(pkg$dst_path, "index.html"))
   expect_true(any(grepl("1.0.0-9000", index, fixed = TRUE)))
 })
@@ -47,7 +56,7 @@ test_that("data_home_sidebar() can be removed", {
 
   # nor later -- so probably not to be tested here?!
   dir_create(path(pkg$dst_path))
-  build_home_index(pkg)
+  suppressMessages(build_home_index(pkg))
   html <- xml2::read_html(path(pkg$dst_path, "index.html"))
   expect_equal(xpath_length(html, ".//aside/*"), 0)
 })