(integration-tests): Added tests checking msg.sender value of eth_call

integration-tests/.prettierrc.js

+module.exports = {
+  ...require('../.prettierrc.js'),
+}

integration-tests/.prettierrc.json

-../.prettierrc.json
\ No newline at end of file

integration-tests/contracts/ValueCalls.sol

@@ -23,6 +23,10 @@ contract ValueContext {
     function getCallValue() public payable returns(uint256) {
         return msg.value;
     }
+
+    function getCaller() external view returns (address){
+        return msg.sender;
+    }
 }
 
 contract ValueCalls is ValueContext {

integration-tests/test/rpc.spec.ts

 import { expect } from './shared/setup'
 
 import { expectApprox, injectL2Context } from '@eth-optimism/core-utils'
-import { Wallet, BigNumber, Contract, ContractFactory } from 'ethers'
+import { Wallet, BigNumber, Contract, ContractFactory, constants } from 'ethers'
 import { serialize } from '@ethersproject/transactions'
 import { ethers } from 'hardhat'
 import {
@@ -233,6 +233,53 @@ describe('Basic RPC tests', () => {
 
       expect(res).to.eq(BigNumber.from(value))
     })
+
+    // https://github.com/ethereum-optimism/optimism/issues/1998
+    it('should use address(0) as the default "from" value', async () => {
+      // Deploy a contract to check msg.caller
+      const Factory__ValueContext: ContractFactory =
+        await ethers.getContractFactory('ValueContext', wallet)
+      const ValueContext: Contract = await Factory__ValueContext.deploy()
+      await ValueContext.deployTransaction.wait()
+
+      // Do the call and check msg.sender
+      const data = ValueContext.interface.encodeFunctionData('getCaller')
+      const res = await provider.call({
+        to: ValueContext.address,
+        data,
+      })
+
+      const [paddedRes] = ValueContext.interface.decodeFunctionResult(
+        'getCaller',
+        res
+      )
+
+      expect(paddedRes).to.eq(constants.AddressZero)
+    })
+
+    it('should correctly use the "from" value', async () => {
+      // Deploy a contract to check msg.caller
+      const Factory__ValueContext: ContractFactory =
+        await ethers.getContractFactory('ValueContext', wallet)
+      const ValueContext: Contract = await Factory__ValueContext.deploy()
+      await ValueContext.deployTransaction.wait()
+
+      const from = wallet.address
+
+      // Do the call and check msg.sender
+      const data = ValueContext.interface.encodeFunctionData('getCaller')
+      const res = await provider.call({
+        to: ValueContext.address,
+        from,
+        data,
+      })
+
+      const [paddedRes] = ValueContext.interface.decodeFunctionResult(
+        'getCaller',
+        res
+      )
+      expect(paddedRes).to.eq(from)
+    })
   })
 
   describe('eth_getTransactionReceipt', () => {