[Lldb-commits] [lldb] [lldb] Fix a bug when disabling the statusline. (PR #169127)

[Jonas Devlieghere via lldb-commits]

https://github.com/JDevlieghere updated https://github.com/llvm/llvm-project/pull/169127

>From 0c2ace38aeaed9de6edddec7e9ed568fc1cdf477 Mon Sep 17 00:00:00 2001
From: Jonas Devlieghere <jonas at devlieghere.com>
Date: Fri, 21 Nov 2025 15:29:43 -0800
Subject: [PATCH 1/3] [lldb] Fix a bug when disabling the statusline.

Currently, disabling the statusline with `settings set show-statusline
false` leaves LLDB in a broken state. The same is true when trying to
toggle the setting again.

The issue was that setting the scroll window to 0 is apparently not
identical to setting it to the correct number of rows, even though some
documentation online incorrectly claims so.

Fixes #166608
---
 lldb/source/Core/Statusline.cpp | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/lldb/source/Core/Statusline.cpp b/lldb/source/Core/Statusline.cpp
index bfbd190fba27c..922aada07e979 100644
--- a/lldb/source/Core/Statusline.cpp
+++ b/lldb/source/Core/Statusline.cpp
@@ -91,7 +91,7 @@ void Statusline::UpdateScrollWindow(ScrollWindowMode mode) {
   if (!stream_sp)
     return;
 
-  const unsigned reduced_scroll_window = m_terminal_height - 1;
+  const unsigned reduced_scroll_rows = m_terminal_height - 1;
   LockedStreamFile locked_stream = stream_sp->Lock();
 
   switch (mode) {
@@ -101,13 +101,14 @@ void Statusline::UpdateScrollWindow(ScrollWindowMode mode) {
     locked_stream.Printf(ANSI_UP_ROWS, 1);
     // Reduce the scroll window.
     locked_stream << ANSI_SAVE_CURSOR;
-    locked_stream.Printf(ANSI_SET_SCROLL_ROWS, reduced_scroll_window);
+    locked_stream.Printf(ANSI_SET_SCROLL_ROWS, reduced_scroll_rows);
     locked_stream << ANSI_RESTORE_CURSOR;
     break;
   case DisableStatusline:
     // Reset the scroll window.
     locked_stream << ANSI_SAVE_CURSOR;
-    locked_stream.Printf(ANSI_SET_SCROLL_ROWS, 0);
+    locked_stream.Printf(ANSI_SET_SCROLL_ROWS,
+                         static_cast<unsigned>(m_terminal_height));
     locked_stream << ANSI_RESTORE_CURSOR;
     // Clear the screen below to hide the old statusline.
     locked_stream << ANSI_CLEAR_BELOW;
@@ -116,7 +117,7 @@ void Statusline::UpdateScrollWindow(ScrollWindowMode mode) {
     // Clear the screen and update the scroll window.
     // FIXME: Find a better solution (#146919).
     locked_stream << ANSI_CLEAR_SCREEN;
-    locked_stream.Printf(ANSI_SET_SCROLL_ROWS, reduced_scroll_window);
+    locked_stream.Printf(ANSI_SET_SCROLL_ROWS, reduced_scroll_rows);
     break;
   }
 

>From 56cbb27cce1126efcbdf3b723fccaf5f849a76f1 Mon Sep 17 00:00:00 2001
From: Jonas Devlieghere <jonas at devlieghere.com>
Date: Fri, 21 Nov 2025 15:47:45 -0800
Subject: [PATCH 2/3] Update test

---
 lldb/test/API/functionalities/statusline/TestStatusline.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lldb/test/API/functionalities/statusline/TestStatusline.py b/lldb/test/API/functionalities/statusline/TestStatusline.py
index ca376cc595f30..6ae74b459d187 100644
--- a/lldb/test/API/functionalities/statusline/TestStatusline.py
+++ b/lldb/test/API/functionalities/statusline/TestStatusline.py
@@ -72,7 +72,9 @@ def test(self):
         self.expect('set set separator "| "')
 
         # Hide the statusline and check or the control character.
-        self.expect("set set show-statusline false", ["\x1b[1;0r"])
+        self.expect(
+            "set set show-statusline false", ["\x1b[1;{}r".format(self.TERMINAL_HEIGHT)]
+        )
 
     def test_no_color(self):
         """Basic test for the statusline with colors disabled."""

>From bcd142a71be04a83a113b2b870fee769e76d5d94 Mon Sep 17 00:00:00 2001
From: Jonas Devlieghere <jonas at devlieghere.com>
Date: Mon, 1 Dec 2025 10:20:55 -0800
Subject: [PATCH 3/3] Fix typo

---
 lldb/test/API/functionalities/statusline/TestStatusline.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lldb/test/API/functionalities/statusline/TestStatusline.py b/lldb/test/API/functionalities/statusline/TestStatusline.py
index 6ae74b459d187..4ffa864120a5c 100644
--- a/lldb/test/API/functionalities/statusline/TestStatusline.py
+++ b/lldb/test/API/functionalities/statusline/TestStatusline.py
@@ -71,7 +71,7 @@ def test(self):
         )
         self.expect('set set separator "| "')
 
-        # Hide the statusline and check or the control character.
+        # Hide the statusline and check for the control character.
         self.expect(
             "set set show-statusline false", ["\x1b[1;{}r".format(self.TERMINAL_HEIGHT)]
         )