Automatically merged updates to draft EIP(s) 2831 (ethereum#2916)

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 - It only modifies existing Draft or Last Call EIP(s)
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EIPS/eip-2831.md

@@ -45,19 +45,48 @@ _This section is non-normative._
 - Transaction Replacement
   - Submitting a transaction with both: the same nonce and a 10% increase in the gas price, of a previous transaction which a user no longer wishes to send. This must occur before the original transaction is included in the blockchain.
 
-### Interface
+### Events
 
-The `data` parameter contains two values: `oldTx` and `newTx`,the transaction hash that's being superseded and the transaction hash of the successor, respectively. Both `oldTx` and `newTx` should be encoded hex numbers as strings with the `0x` prefixed.
+These methods **MUST** be implemented per the Node.js [`EventEmitter` API](https://nodejs.org/api/events.html).
 
-```JavaScript
-interface TxReplacement extends ProviderMessage {
-  readonly type: 'tx_replacement';
-  readonly data: {
-    readonly oldTx: string;
-    readonly newTx: string;
-  };
+The following two events must be implemented to catch both cases of a transaction replacement: `tx_speedup` and `tx_cancel`.
+
+A `tx_speedup` is defined as a transaction replacement in which the user wishes to adjust the `gasPrice`, to potentially receive a fast block inclusion. For a `tx_speedup` to be considered valid, the replacement tx must contain the **same** following properties as the one it supersedes:
+- Nonce
+- To
+- Value
+- Data
+
+```typescript
+interface txSpeedupInfo {
+  readonly oldTx: string;
+  readonly newTx: string;
+  readonly nonce: string;
+  readonly from: string;
 }
+
+Provider.on('tx_speedup', listener: (txSpeedupInfo: txSpeedupInfo) => void): Provider;
 ```
+This event emits the old transaction hash (`oldTx`), the new transaction hash (`newTx`), the nonce used for both transactions (`nonce`), and the signing address for the transaction (`from`).
+
+A `tx_cancel` is defined as a transaction replacement in which the user wishes to nullify a previous transaction before its inclusion. For a `tx_cancel` to be considered valid, the replacement tx must contain the following properties:
+- The same nonce as the superseded transaction
+- The same From and To
+- Zero value
+- No data
+
+```typescript
+interface txCancelInfo {
+  readonly oldTx: string;
+  readonly newTx: string;
+  readonly nonce: string;
+  readonly from: string;
+}
+
+Provider.on('tx_cancel', listener: (txCancelInfo: txCancelInfo) => void): Provider;
+```
+This event emits the old transaction hash (`oldTx`), the new transaction hash (`newTx`), the nonce used for both transactions (`nonce`), and the signing address for the transaction (`from`).
+
 
 ## Rationale
 
@@ -94,13 +123,6 @@ These examples assume a web browser environment.
 // Please consult the Provider implementation's documentation.
 const ethereum = window.ethereum;
 
-ethereum.on('message', (message) => {
-  if (message.type === 'tx_replacement') {
-    const { oldTx, newTx } = message.data;
-    console.log(`Tx ${oldTx} was cancelled, the new hash is ${newTx}`)
-  }
-});
-
 const transactionParameters = { ... } // Fill in parameters
 
 ethereum
@@ -109,6 +131,15 @@ ethereum
     params: [transactionParameters],
   })
   .then((txHash) => {
+    ethereum.on('tx_cancel', (info) => {
+      const { oldTx, newTx, nonce, from } = message.data;
+      console.log(`Tx ${oldTx} with nonce ${nonce} from ${from} was cancelled, the new hash is ${newTx}`)
+    });
+    ethereum.on('tx_speedup', (info) => {
+      const { oldTx, newTx, nonce, from } = message.data;
+      console.log(`Tx ${oldTx} with nonce ${nonce} from ${from} was sped up, the new hash is ${newTx}`)
+    });
+
     console.log(`Transaction hash ${txHash}`)
   })
   .catch((error) => {