From d4473c0e97bbe1cec7c8c067c5b95e48d655fb83 Mon Sep 17 00:00:00 2001
From: saket3395 <sakettulsan95@gmail.com>
Date: Fri, 31 Jul 2026 12:07:28 +0530
Subject: [PATCH] fix: correct DataTable tooltip position on paginated pages

Fixes #1848. Tooltip row index was resolved against the virtualized
(page-local) row twice: once when handling the mouse event, and again
when matching the tooltip condition/data lookup. On page 1 these two
resolutions coincide, masking the bug; on later pages they diverge,
so tooltips render using the wrong row's position/data.

Ports the fix from plotly/dash-table#906 (pre-merge into this repo):
- cellEvents.ts: store the raw virtualized idx in currentTooltip.row
  instead of pre-resolving it, matching how handleMoveHeader already
  behaves for header tooltips.
- tooltip.ts: resolve virtualized.indices[row - offset.rows] once,
  at lookup time in getSelectedTooltip, instead of relying on a
  pre-resolved value.

Manually verified the diff is a faithful port of #906 and consistent
with the surrounding code (handleMoveHeader already stores the raw
idx). Not yet run through the JS build/test suite locally.
---
 .../src/dash-table/derived/table/tooltip.ts           |  2 +-
 .../dash-table/src/dash-table/handlers/cellEvents.ts  | 11 +++++------
 2 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/components/dash-table/src/dash-table/derived/table/tooltip.ts b/components/dash-table/src/dash-table/derived/table/tooltip.ts
index 54620dea99..f2651df322 100644
--- a/components/dash-table/src/dash-table/derived/table/tooltip.ts
+++ b/components/dash-table/src/dash-table/derived/table/tooltip.ts
@@ -42,7 +42,7 @@ function getSelectedTooltip(
               return (
                   !tt.if ||
                   (ifColumnId(tt.if, id) &&
-                      ifRowIndex(tt.if, row) &&
+                      ifRowIndex(tt.if, virtualized.indices[row - virtualized.offset.rows]) &&
                       ifFilter(
                           tt.if,
                           virtualized.data[row - virtualized.offset.rows]
diff --git a/components/dash-table/src/dash-table/handlers/cellEvents.ts b/components/dash-table/src/dash-table/handlers/cellEvents.ts
index 8ece59511e..6fc6d02dfa 100644
--- a/components/dash-table/src/dash-table/handlers/cellEvents.ts
+++ b/components/dash-table/src/dash-table/handlers/cellEvents.ts
@@ -160,13 +160,13 @@ export const handleEnter = (
     idx: number,
     i: number
 ) => {
-    const {setState, virtualized, visibleColumns} = propsFn();
+    const {setState, visibleColumns} = propsFn();
 
     setState({
         currentTooltip: {
             header: false,
             id: visibleColumns[i].id,
-            row: virtualized.indices[idx - virtualized.offset.rows]
+            row: idx
         }
     });
 };
@@ -202,15 +202,14 @@ export const handleMove = (
     idx: number,
     i: number
 ) => {
-    const {currentTooltip, setState, virtualized, visibleColumns} = propsFn();
+    const {currentTooltip, setState, visibleColumns} = propsFn();
 
     const c = visibleColumns[i];
-    const realIdx = virtualized.indices[idx - virtualized.offset.rows];
 
     if (
         currentTooltip &&
         currentTooltip.id === c.id &&
-        currentTooltip.row === realIdx &&
+        currentTooltip.row === idx &&
         !currentTooltip.header
     ) {
         return;
@@ -220,7 +219,7 @@ export const handleMove = (
         currentTooltip: {
             header: false,
             id: c.id,
-            row: realIdx
+            row: idx
         }
     });
 };