From 6fff099d9468fa3801f149b22e148c974ecf20c9 Mon Sep 17 00:00:00 2001
From: Taylor Jones <tay1orjones@github.com>
Date: Fri, 18 Sep 2026 13:03:15 -0500
Subject: [PATCH] prevent virtualized SelectPanel measurement warnings

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>
---
 .../fix-virtualized-select-panel-measurement.md   |  5 +++++
 packages/react/src/ActionList/Item.test.tsx       | 15 +++++++++++++++
 packages/react/src/ActionList/Item.tsx            |  2 +-
 .../FilteredActionList.test.tsx                   | 15 +++++++++++++++
 4 files changed, 36 insertions(+), 1 deletion(-)
 create mode 100644 .changeset/fix-virtualized-select-panel-measurement.md

diff --git a/.changeset/fix-virtualized-select-panel-measurement.md b/.changeset/fix-virtualized-select-panel-measurement.md
new file mode 100644
index 00000000000..622f2df5849
--- /dev/null
+++ b/.changeset/fix-virtualized-select-panel-measurement.md
@@ -0,0 +1,5 @@
+---
+'@primer/react': patch
+---
+
+SelectPanel: Prevent console warnings when measuring virtualized items
diff --git a/packages/react/src/ActionList/Item.test.tsx b/packages/react/src/ActionList/Item.test.tsx
index 1dbfb0d453b..0a34bacba76 100644
--- a/packages/react/src/ActionList/Item.test.tsx
+++ b/packages/react/src/ActionList/Item.test.tsx
@@ -387,6 +387,21 @@ describe('ActionList.Item', () => {
     expect(tabs).toHaveLength(3)
   })
 
+  it('should forward a list-semantic item ref only to the outer list item', () => {
+    const ref = vi.fn<(node: HTMLLIElement | null) => void>()
+    const {getByRole} = HTMLRender(
+      <ActionList role="listbox" aria-label="Projects">
+        <ActionList.Item ref={ref} role="option">
+          Primer React
+        </ActionList.Item>
+      </ActionList>,
+    )
+    const option = getByRole('option')
+
+    expect(ref.mock.calls.filter(([node]) => node !== null)).toEqual([[option]])
+    expect(option.tagName).toBe('LI')
+  })
+
   it('should preserve consumer ref when tooltip wraps trigger', async () => {
     const user = userEvent.setup()
 
diff --git a/packages/react/src/ActionList/Item.tsx b/packages/react/src/ActionList/Item.tsx
index 1606952e3e1..f811925983f 100644
--- a/packages/react/src/ActionList/Item.tsx
+++ b/packages/react/src/ActionList/Item.tsx
@@ -340,7 +340,7 @@ const UnwrappedItem = <As extends React.ElementType = 'li'>(
             className={classes.ActionListContent}
             data-size={size}
             // @ts-ignore: ItemWrapper is polymorphic and the ref type depends on the rendered element ('button' or 'li')
-            ref={forwardedRef}
+            ref={listSemantics ? null : forwardedRef}
           >
             {/* Reset TooltipContext so that child components don't detect
                 the ConditionalTooltip and suppress their own internal tooltips. */}
diff --git a/packages/react/src/FilteredActionList/FilteredActionList.test.tsx b/packages/react/src/FilteredActionList/FilteredActionList.test.tsx
index f90ba4fd845..0263b63d2bd 100644
--- a/packages/react/src/FilteredActionList/FilteredActionList.test.tsx
+++ b/packages/react/src/FilteredActionList/FilteredActionList.test.tsx
@@ -100,6 +100,21 @@ describe('FilteredActionList', () => {
       ).toBeInTheDocument()
     })
   })
+
+  it('does not warn when measuring virtualized items', () => {
+    const warnSpy = vi.spyOn(console, 'warn').mockImplementation(() => {})
+
+    try {
+      const {container} = render(<FilteredActionList items={items} onFilterChange={vi.fn()} virtualized />)
+
+      expect(container.querySelector('[data-index]')).toBeInTheDocument()
+      expect(warnSpy.mock.calls.flat().join(' ')).not.toContain(
+        "Missing attribute name 'data-index={index}' on measured element.",
+      )
+    } finally {
+      warnSpy.mockRestore()
+    }
+  })
 })
 
 describe('FilteredActionListBodyLoader', () => {