## Summary
Fixes [#21014](https://github.com/twentyhq/twenty/issues/21014).
When two pie chart widgets shared the same group-by field (and therefore
the same slice ids) but used different aggregation operators (e.g.
`count` vs `sum`), the arc-link labels would mirror between the two
charts — both ending up showing either the count or the sum values,
depending on render order. Center metrics stayed correct.
**Root cause.** Nivo's `ArcLinkLabelsLayer` and `ArcsLayer` (from
`@nivo/arcs`) wire `react-spring`'s `useTransition` with `keys: e =>
e.id`. When two `<ResponsivePie>` instances render with overlapping ids,
the transitioned data bleeds across charts. The center metric is
unaffected because it's computed by a separate hook
(`usePieChartCenterMetricData`).
**Fix.** Namespace the Nivo-computed slice id per widget by passing an
`id` accessor to `<ResponsivePie>`:
```tsx
id={(datum) => `${id}:${String(datum.id)}`}
```
Lookups inside the widget switch to `datum.data.id` (the original,
un-namespaced id stored on the raw datum), so value/percentage
formatting, the custom tooltip, and the legend hover-dim behavior all
keep working.
Touched files:
- `GraphWidgetPieChart.tsx` — add `id` accessor
- `CustomArcsLayer.tsx` — compare legend highlight against
`datum.data.id`
- `getPieChartFormattedValue.ts`, `getPieChartTooltipData.ts` — match on
`datum.data.id`
- Tests for both utils get a regression case covering the namespaced
computed id
## Test plan
- [ ] `npx jest getPieChartFormattedValue` ✅
- [ ] `npx jest getPieChartTooltipData` ✅
- [ ] `npx tsc --noEmit` ✅
- [ ] Manual: dashboard with two pies on the same group-by field, one
`count` and one `sum`, "Display data label" on for both — confirm each
chart shows its own metric on the slices, and the central total is
unchanged.
- [ ] Manual: hover a legend item — the matching slice in that chart
stays solid while the others dim, and the sibling chart is not affected.
- [ ] Manual: clicking a slice still drills into the correctly filtered
view.
