fix: Avoid unnecessary NotebookTab updates (#5068)

Co-authored-by: Rasmus Karlsson <rasmus.karlsson@pajlada.com>

CHANGELOG.md

@@ -108,6 +108,7 @@
 - Dev: Refactor Args to be less of a singleton. (#5041)
 - Dev: Channels without any animated elements on screen will skip updates from the GIF timer. (#5042, #5043, #5045)
 - Dev: Autogenerate docs/plugin-meta.lua. (#5055)
+- Dev: Fix `NotebookTab` emitting updates for every message. (#5068)
 
 ## 2.4.6
 

src/widgets/helper/NotebookTab.cpp

@@ -346,17 +346,25 @@ bool NotebookTab::isLive() const
 
 void NotebookTab::setHighlightState(HighlightState newHighlightStyle)
 {
-    if (this->isSelected() || (!this->highlightEnabled_ &&
-                               newHighlightStyle == HighlightState::NewMessage))
+    if (this->isSelected())
     {
         return;
     }
-    if (this->highlightState_ != HighlightState::Highlighted)
+
+    if (!this->highlightEnabled_ &&
+        newHighlightStyle == HighlightState::NewMessage)
     {
-        this->highlightState_ = newHighlightStyle;
+        return;
+    }
 
-        this->update();
+    if (this->highlightState_ == newHighlightStyle ||
+        this->highlightState_ == HighlightState::Highlighted)
+    {
+        return;
     }
+
+    this->highlightState_ = newHighlightStyle;
+    this->update();
 }
 
 HighlightState NotebookTab::highlightState() const

tests/src/NotebookTab.cpp

@@ -91,8 +91,7 @@ TEST_F(NotebookTabFixture, UpgradeHighlightState)
 /// The highlight state must stay as NewMessage when called twice
 TEST_F(NotebookTabFixture, SameHighlightStateNewMessage)
 {
-    // XXX: This only updates the state once, so it should only update once
-    EXPECT_CALL(this->tab, update).Times(Exactly(2));
+    EXPECT_CALL(this->tab, update).Times(Exactly(1));
     EXPECT_EQ(this->tab.highlightState(), HighlightState::None);
     this->tab.setHighlightState(HighlightState::NewMessage);
     EXPECT_EQ(this->tab.highlightState(), HighlightState::NewMessage);