What is the current behavior?

The dataKey does not exist in the payload of the Legend within the PieChart.

{
  "value": "safari",
  "color": "",
  "payload": {
    "browser": "safari",
    "downloads": 2159,
    "visits": 4048
  },
  "type": "rect"
}

The payload of the Tooltip contains a dataKey.

{
  "stroke": "",
  "dataKey": "visits",
  "nameKey": "browser",
  "name": "chrome",
  "hide": false,
  "graphicalItemId": "recharts-pie-_r_1_",
  "payload": {
    "browser": "chrome",
    "downloads": 4545,
    "visits": 2764
  },
  "value": 2764
}

Other charts (LineChart and AreaChart) have a dataKey in their payload. For compatibility, we should include dataKey within the payload.

Additionally, if multiple Pie elements exist within a PieChart, the payload of the Legend cannot determine which Pie the data belongs to if the dataKey is missing.

What is the expected behavior?

Please include the dataKey in the payload of Legend.

{
  "dataKey": "visits",
  "value": "safari",
  "color": "",
  "payload": {
    "browser": "safari",
    "downloads": 2159,
    "visits": 4048
  },
  "type": "rect"
}

Which versions of Recharts, and which browser / OS are affected by this issue? Did this work in previous versions of Recharts?

The version is 3.7.0, and dataKey has likely never been provided.