estimateGas supports blocktag (#894)

* estimateGas supports blocktag

* fix

* fix

* fix

packages/eth-providers/src/base-provider.ts

@@ -928,8 +928,15 @@ export abstract class BaseProvider extends AbstractProvider {
    * @param transaction The transaction to estimate the gas of
    * @returns The estimated gas used by this transaction
    */
-  estimateGas = async (transaction: Deferrable<TransactionRequest>): Promise<BigNumber> => {
-    const { usedGas, gasLimit, usedStorage } = await this.estimateResources(transaction);
+  estimateGas = async (
+    transaction: Deferrable<TransactionRequest>,
+    blockTag?: BlockTag | Promise<BlockTag>
+  ): Promise<BigNumber> => {
+    const blockHash = blockTag && blockTag !== 'latest'
+      ? await this._getBlockHash(blockTag)
+      : undefined;  // if blockTag is latest, avoid explicit blockhash for better performance
+
+    const { usedGas, gasLimit, usedStorage } = await this.estimateResources(transaction, blockHash);
 
     const tx = await resolveProperties(transaction);
     const data = tx.data?.toString() ?? '0x';
@@ -948,7 +955,7 @@ export abstract class BaseProvider extends AbstractProvider {
       ? this.api.tx.evm.call(...callParams)
       : this.api.tx.evm.create(...createParams);
 
-    let txFee = await this._estimateGasCost(extrinsic);
+    let txFee = await this._estimateGasCost(extrinsic, blockHash);
     txFee = txFee.mul(gasLimit).div(usedGas); // scale it to the same ratio when estimate passing gasLimit
 
     if (usedStorage.gt(0)) {
@@ -965,9 +972,13 @@ export abstract class BaseProvider extends AbstractProvider {
     return encodeGasLimit(txFee, gasPrice, gasLimit, usedStorage, isTokenTransfer);
   };
 
-  _estimateGasCost = async (extrinsic: SubmittableExtrinsic<'promise', ISubmittableResult>) => {
+  _estimateGasCost = async (
+    extrinsic: SubmittableExtrinsic<'promise', ISubmittableResult>,
+    at?: string,
+  ) => {
+    const apiAt = await this.api.at(at ?? await this.bestBlockHash);
+
     const u8a = extrinsic.toU8a();
-    const apiAt = await this.api.at(await this.bestBlockHash);
     const lenIncreaseAfterSignature = 100;    // approximate length increase after signature
     const feeDetails = await apiAt.call.transactionPaymentApi.queryFeeDetails(
       u8a,
@@ -1098,7 +1109,8 @@ export abstract class BaseProvider extends AbstractProvider {
    * @returns The estimated resources used by this transaction
    */
   estimateResources = async (
-    transaction: Deferrable<TransactionRequest>
+    transaction: Deferrable<TransactionRequest>,
+    blockHash?: string,
   ): Promise<{
     usedGas: BigNumber;
     gasLimit: BigNumber;
@@ -1116,7 +1128,7 @@ export abstract class BaseProvider extends AbstractProvider {
       storageLimit: STORAGE_LIMIT,
     };
 
-    const gasInfo = await this._ethCall(txRequest);
+    const gasInfo = await this._ethCall(txRequest, blockHash);
     const usedGas = BigNumber.from(gasInfo.used_gas).toNumber();
     const usedStorage = gasInfo.used_storage;
 
@@ -1523,7 +1535,7 @@ export abstract class BaseProvider extends AbstractProvider {
 
     switch (blockTag) {
       case 'pending': {
-        return logger.throwError('pending tag not implemented', Logger.errors.UNSUPPORTED_OPERATION);
+        return logger.throwError('pending tag not supported', Logger.errors.UNSUPPORTED_OPERATION);
       }
       case 'latest': {
         return this.safeMode ? this.finalizedBlockHash : this.bestBlockHash;

packages/eth-rpc-adapter/src/__tests__/e2e/endpoint.test.ts

@@ -1940,6 +1940,9 @@ describe('endpoint', () => {
       const { gasLimit } = await estimateGas(tx);
       const bbb = (gasLimit.toNumber() % 100000) / 100;
 
+      const { gasLimit: gasLimitWithBlockTag } = await estimateGas(tx, 'latest');
+      expect(gasLimitWithBlockTag.toBigInt()).to.equal(gasLimit.toBigInt());
+
       // should be passing gasLimit instead of usedGas
       expect(bbb).to.gt(GAS_MONSTER_GAS_REQUIRED / 30000);
 

packages/eth-rpc-adapter/src/__tests__/e2e/utils.ts

@@ -1,4 +1,5 @@
 import { BigNumber, ContractFactory, Signer } from 'ethers';
+import { BlockTagish } from '@acala-network/eth-providers';
 import { Log, TransactionRequest } from '@ethersproject/abstract-provider';
 import { expect } from 'vitest';
 import { hexValue } from '@ethersproject/bytes';
@@ -71,9 +72,9 @@ export const eth_getTransactionByHash_karura = rpcGet('eth_getTransactionByHash'
 export const eth_getBlockByNumber_karura = rpcGet('eth_getBlockByNumber', KARURA_ETH_RPC_URL);
 export const eth_getStorageAt_karura = rpcGet('eth_getStorageAt', KARURA_ETH_RPC_URL);
 
-export const estimateGas = async (tx: TransactionRequest) => {
+export const estimateGas = async (tx: TransactionRequest, blockTag?: BlockTagish) => {
   const gasPrice = (await eth_gasPrice([])).data.result;
-  const res = await eth_estimateGas([{ ...tx, gasPrice }]);
+  const res = await eth_estimateGas([{ ...tx, gasPrice }, blockTag]);
   if (res.data.error) {
     throw new Error(res.data.error.message);
   }

packages/eth-rpc-adapter/src/eip1193-bridge.ts

@@ -293,8 +293,8 @@ class Eip1193BridgeImpl {
    * @returns GAS USED - the amount of gas used.
    */
   async eth_estimateGas(params: any[]): Promise<string> {
-    validate([{ type: 'transaction' }], params);
-    const val = await this.#provider.estimateGas(params[0]);
+    validate([{ type: 'transaction' }, { type: 'block?' }], params);
+    const val = await this.#provider.estimateGas(params[0], params[1]);
     return hexValue(val);
   }
 

packages/eth-rpc-adapter/src/validate.ts

@@ -4,6 +4,7 @@ export type Schema = {
   type:
     | 'address'
     | 'block'
+    | 'block?'
     | 'transaction'
     | 'blockHash'
     | 'trasactionHash'
@@ -148,6 +149,10 @@ export const validate = (schema: Schema, data: unknown[]) => {
           validateBlock(data[i]);
           break;
         }
+        case 'block?': {
+          data[i] && validateBlock(data[i]);
+          break;
+        }
         case 'transaction': {
           validateTransaction(data[i]);
           break;