Work around receipts root calculation for Stable network (#428)

Work around receipts root calculation for Stable network.
It uses gasUsed instead of cumulativeGasUsed in receipts root

Author: kalabukdima

evm/evm-rpc/src/chain-utils.ts

@@ -16,11 +16,13 @@ export class ChainUtils {
     public isPolygonMainnet: boolean
     public isHyperliquidMainnet: boolean
     public isHyperliquidTestnet: boolean
+    public isStable: boolean
 
     constructor(chainId: Qty) {
         this.isPolygonMainnet = chainId == '0x89'
         this.isHyperliquidMainnet = chainId == '0x3e7'
         this.isHyperliquidTestnet = chainId == '0x3e6'
+        this.isStable = chainId == '0x3dc' || chainId == '0x899' // Chain ID 988 (mainnet) or 2201 (testnet)
     }
 
     calculateBlockHash(block: GetBlock) {
@@ -86,6 +88,11 @@ export class ChainUtils {
             receipts = receipts.filter(receipt => !isHyperliquidSystemReceipt(receipt))
         }
 
+        // Stable chain uses gasUsed instead of cumulativeGasUsed in receipts root
+        if (this.isStable) {
+            return receiptsRoot(receipts, {useGasUsed: true})
+        }
+
         return receiptsRoot(receipts)
     }
 

evm/evm-rpc/src/verification.ts

@@ -281,14 +281,26 @@ function decodeLogs(logs: Log[]) {
 }
 
 
-function encodeReceipt(receipt: Receipt): Buffer {
+export interface ReceiptEncodingOptions {
+    /**
+     * Use gasUsed instead of cumulativeGasUsed when encoding receipts.
+     * This is needed for chains like Stable (chain ID 988) that deviate from
+     * the Ethereum standard by using per-transaction gas instead of cumulative.
+     */
+    useGasUsed?: boolean
+}
+
+
+function encodeReceipt(receipt: Receipt, options?: ReceiptEncodingOptions): Buffer {
     let type = receipt.type == '0x0' ? Buffer.alloc(0) : RLP.encode(qty2Int(receipt.type))
     let payload: Uint8Array
+    // Use gasUsed instead of cumulativeGasUsed for certain chains (e.g., Stable)
+    let gasField = options?.useGasUsed ? receipt.gasUsed : receipt.cumulativeGasUsed
     if (receipt.type == '0x7e') {
         // https://github.com/ethereum-optimism/specs/blob/main/specs/protocol/deposits.md#deposit-receipt
         payload = RLP.encode([
             qty2Int(receipt.status),
-            BigInt(receipt.cumulativeGasUsed),
+            BigInt(gasField),
             decodeHex(receipt.logsBloom),
             decodeLogs(receipt.logs),
             BigInt(assertNotNull(receipt.depositNonce, 'receipt.depositNonce is missing')),
@@ -297,7 +309,7 @@ function encodeReceipt(receipt: Receipt): Buffer {
     } else {
         payload = RLP.encode([
             qty2Int(receipt.status),
-            BigInt(receipt.cumulativeGasUsed),
+            BigInt(gasField),
             decodeHex(receipt.logsBloom),
             decodeLogs(receipt.logs),
         ])
@@ -306,15 +318,15 @@ function encodeReceipt(receipt: Receipt): Buffer {
 }
 
 
-export async function receiptsRoot(receipts: Receipt[]) {
+export async function receiptsRoot(receipts: Receipt[], options?: ReceiptEncodingOptions) {
     let trie = await createMPT()
 
     for (let idx = 0; idx < receipts.length; idx++) {
         let receipt = receipts[idx]
         let key = RLP.encode(idx)
         let value: Buffer
         try {
-            value = encodeReceipt(receipt)
+            value = encodeReceipt(receipt, options)
         } catch (err: any) {
             throw addErrorContext(err, {
                 transactionIndex: qty2Int(receipt.transactionIndex),