From 42956e03056e3dc2ce8d26b55740b625c0a8f706 Mon Sep 17 00:00:00 2001
From: Tim Abbott <tabbott@zulip.com>
Date: Wed, 31 Jan 2024 13:44:33 -0800
Subject: [PATCH] message_viewport: Rename at_bottom for clarity.

---
 web/src/message_scroll.js   | 2 +-
 web/src/message_viewport.ts | 9 +++++----
 web/src/navigate.js         | 2 +-
 web/src/ui_init.js          | 2 +-
 4 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/web/src/message_scroll.js b/web/src/message_scroll.js
index efa231c7f7..647e7f0cac 100644
--- a/web/src/message_scroll.js
+++ b/web/src/message_scroll.js
@@ -88,7 +88,7 @@ export function scroll_finished() {
         });
     }
 
-    if (message_viewport.at_bottom()) {
+    if (message_viewport.at_rendered_bottom()) {
         message_fetch.maybe_load_newer_messages({
             msg_list: message_lists.current,
         });
diff --git a/web/src/message_viewport.ts b/web/src/message_viewport.ts
index acd099ea1b..34eba55cdf 100644
--- a/web/src/message_viewport.ts
+++ b/web/src/message_viewport.ts
@@ -75,7 +75,7 @@ export function message_viewport_info(): MessageViewportInfo {
 // rendered message feed; messages that are not displayed due to a
 // limited render window or because they have not been fetched from
 // the server are not considered.
-export function at_bottom(): boolean {
+export function at_rendered_bottom(): boolean {
     const bottom = scrollTop() + height();
     const full_height = $scroll_container.prop("scrollHeight");
 
@@ -86,8 +86,9 @@ export function at_bottom(): boolean {
     return bottom + 2 >= full_height;
 }
 
-// This differs from at_bottom in that it only requires the bottom message to
-// be visible, but you may be able to scroll down further.
+// This differs from at_rendered_bottom in that it only requires the
+// bottom message to be visible, but you may be able to scroll down
+// further to see the rest of that message.
 export function bottom_rendered_message_visible(): boolean {
     const $last_row = rows.last_visible();
     if ($last_row.length) {
@@ -485,7 +486,7 @@ export function keep_pointer_in_view(): void {
     }
 
     function message_is_far_enough_up(): boolean {
-        return at_bottom() || $next_row.get_offset_to_window().top <= bottom_threshold;
+        return at_rendered_bottom() || $next_row.get_offset_to_window().top <= bottom_threshold;
     }
 
     function adjust(
diff --git a/web/src/navigate.js b/web/src/navigate.js
index e0ee50bb77..7526cc3892 100644
--- a/web/src/navigate.js
+++ b/web/src/navigate.js
@@ -108,7 +108,7 @@ export function page_up() {
 }
 
 export function page_down() {
-    if (message_viewport.at_bottom() && !message_lists.current.visibly_empty()) {
+    if (message_viewport.at_rendered_bottom() && !message_lists.current.visibly_empty()) {
         message_lists.current.select_id(message_lists.current.last().id, {then_scroll: false});
         unread_ops.process_visible();
     } else {
diff --git a/web/src/ui_init.js b/web/src/ui_init.js
index 657a0eeeb8..08b93983b4 100644
--- a/web/src/ui_init.js
+++ b/web/src/ui_init.js
@@ -199,7 +199,7 @@ export function initialize_kitchen_sink_stuff() {
 
         if (delta < 0 && message_viewport.at_top()) {
             navigate.up();
-        } else if (delta > 0 && message_viewport.at_bottom()) {
+        } else if (delta > 0 && message_viewport.at_rendered_bottom()) {
             navigate.down();
         }