feat: added ContractCaller solidity example contract (#534)

contracts/yul/contract-caller/ContractCaller.sol

@@ -0,0 +1,106 @@
+// SPDX-License-Identifier: Apache-2.0
+pragma solidity ^0.8.20;
+
+contract TargetContract {
+    uint256 count;
+
+    constructor(uint256 _count) {
+        count = _count;
+    }
+
+    function setCount(uint256 _count) external {
+        count = _count;
+    }
+
+    function getCount() external view returns (uint256) {
+        return count;
+    }
+}
+
+
+contract ContractCaller {
+    uint256 public count;
+
+    event CallResult(bool success);
+    event CallReturnedData(uint256 count);
+
+    /// call(g, a, v, in, insize, out, outsize)
+    /// `g`: Amount of gas to be provided for the execution of called contract
+    /// `a`: Address of the called contract
+    /// `v`: callvalue() (a.k.a. msg.value)
+    /// `in`: Input data that will be provided to the called contract
+    /// `insize`: Input data size
+    /// `out`: Output data produced by the called contract
+    /// `outsize`: Output data size
+    function call(uint256 gasLimit, address payable _targetContractAddress, bytes memory input) external payable {
+        bool success;
+        uint256 returnedData;
+
+        assembly {
+            let returnedDataPlaceholder := mload(0x40) // load the data at free memory pointer
+
+            success := call(gasLimit, _targetContractAddress, callvalue(), add(input, 0x20), mload(input), returnedDataPlaceholder, 0x20)
+
+            returnedData := mload(returnedDataPlaceholder)
+        }
+
+        emit CallResult(success);
+        emit CallReturnedData(returnedData);
+    }
+
+    /// staticcall(g, a, in, insize, out, outsize) - identical to `call` but do not allow state modifications
+    /// `g`: Amount of gas to be provided for the execution of called contract
+    /// `a`: Address of the called contract
+    /// `in`: Input data that will be provided to the called contract
+    /// `insize`: Input data size
+    /// `out`: Output data produced by the called contract
+    /// `outsize`: Output data size
+    function staticcall(uint256 gasLimit, address payable _targetContractAddress, bytes memory input) external {
+        bool success;
+        uint256 returnedData;
+
+        assembly {
+            let returnedDataPlaceholder := mload(0x40) // load the data at free memory pointer
+
+            success := staticcall(gasLimit, _targetContractAddress, add(input, 0x20), mload(input), returnedDataPlaceholder, 0x20)
+
+            returnedData := mload(returnedDataPlaceholder)
+        }
+
+        emit CallResult(success);
+        emit CallReturnedData(returnedData);
+    }
+
+
+    /// callcode(g, a, v, in, insize, out, outsize) - identical to `call` but only use the code from a and stay in the context of the current contract otherwise
+    /// `g`: Amount of gas to be provided for the execution of called contract
+    /// `a`: Address of the called contract
+    /// `in`: Input data that will be provided to the called contract
+    /// `insize`: Input data size
+    /// `out`: Output data produced by the called contract
+    /// `outsize`: Output data size
+    function callCode(uint256 gasLimit, address payable _targetContractAddress, bytes memory input) external payable {
+        bool success;
+        assembly {
+            /// @notice callcode uses the code from `_targetContractAddress` to update current contract's states
+            success := callcode(gasLimit, _targetContractAddress, callvalue(), add(input, 0x20), mload(input), 0, 0)
+        }
+        emit CallResult(success);
+    }
+
+    /// delegatecall(g, a, in, insize, out, outsize) - identical to `callcode` but also keep caller and callvalue 
+    /// `g`: Amount of gas to be provided for the execution of called contract
+    /// `a`: Address of the called contract
+    /// `in`: Input data that will be provided to the called contract
+    /// `insize`: Input data size
+    /// `out`: Output data produced by the called contract
+    /// `outsize`: Output data size
+    function delegateCall(uint256 gasLimit, address payable _targetContractAddress, bytes memory input) external {
+        bool success;
+        assembly {
+            /// @notice delegatecall uses the code from `_targetContractAddress` to update current contract's states
+            success := delegatecall(gasLimit, _targetContractAddress, add(input, 0x20), mload(input), 0, 0)
+        }
+        emit CallResult(success);
+    }
+}

contracts/yul/math-coverage/MatchCoverage.sol

@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: UNLICENSED
+// SPDX-License-Identifier: Apache-2.0
 pragma solidity ^0.8.20;
 
 contract MathCoverage {

test/yul/contract-caller/ContractCaller.js

@@ -0,0 +1,158 @@
+/*-
+ *
+ * Hedera Smart Contracts
+ *
+ * Copyright (C) 2023 Hedera Hashgraph, LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+const { expect } = require('chai')
+const { ethers } = require('hardhat')
+
+describe('@solidityequiv5 Contract Caller Tests', async () => {
+  let contractCaller, targetContract, getCountEncodedSig, setCountEncodedSig
+  const COUNT_A = 3
+  const GAS = 1_000_000
+  const INITIAL_COUNT = 9
+
+  beforeEach(async () => {
+    // deploy contracts
+    const contractCallerFactory = await ethers.getContractFactory(
+      'ContractCaller'
+    )
+    const targetContractFactory = await ethers.getContractFactory(
+      'TargetContract'
+    )
+    contractCaller = await contractCallerFactory.deploy()
+    targetContract = await targetContractFactory.deploy(INITIAL_COUNT)
+
+    // prepare encoded function signatures
+    getCountEncodedSig =
+      targetContract.interface.encodeFunctionData('getCount()')
+
+    setCountEncodedSig = targetContract.interface.encodeFunctionData(
+      'setCount(uint256)',
+      [COUNT_A]
+    )
+  })
+
+  it('Should execute call(g, a, v, in, insize, out, outsize)', async () => {
+    // prepare transactions
+    const callSetCountTx = await contractCaller.call(
+      GAS,
+      targetContract.address,
+      setCountEncodedSig
+    )
+    const callGetCountTx = await contractCaller.call(
+      GAS,
+      targetContract.address,
+      getCountEncodedSig
+    )
+
+    // wait for the receipts
+    const callSetCountReceipt = await callSetCountTx.wait()
+    const callGetCountReceipt = await callGetCountTx.wait()
+
+    // extract events
+    const [callSetCountResult] = callSetCountReceipt.events.map(
+      (e) => e.event === 'CallResult' && e
+    )[0].args
+    const [callGetCountResult] = callGetCountReceipt.events.map(
+      (e) => e.event === 'CallResult' && e
+    )[0].args
+    const [callGetCountReturnedData] = callGetCountReceipt.events.map(
+      (e) => e.event === 'CallReturnedData' && e
+    )[1].args
+
+    // assertion
+    expect(callSetCountResult).to.be.true
+    expect(callGetCountResult).to.be.true
+    expect(callGetCountReturnedData).to.eq(COUNT_A)
+  })
+
+  it('Should execute staticcall(g, a, in, insize, out, outsize)', async () => {
+    // prepare transactions
+    const callGetCountTx = await contractCaller.staticcall(
+      GAS,
+      targetContract.address,
+      getCountEncodedSig
+    )
+
+    // wait for the receipts
+    const callGetCountReceipt = await callGetCountTx.wait()
+
+    // extract events
+    const [callGetCountResult] = callGetCountReceipt.events.map(
+      (e) => e.event === 'CallResult' && e
+    )[0].args
+    const [callGetCountReturnedData] = callGetCountReceipt.events.map(
+      (e) => e.event === 'CallReturnedData' && e
+    )[1].args
+
+    // assertion
+    expect(callGetCountResult).to.be.true
+    expect(callGetCountReturnedData).to.eq(INITIAL_COUNT)
+  })
+
+  it('Should execute callcode(g, a, v, in, insize, out, outsize)', async () => {
+    // prepare transactions
+    const callSetCountTx = await contractCaller.callCode(
+      GAS,
+      targetContract.address,
+      setCountEncodedSig
+    )
+
+    // wait for the receipts
+    const callSetCountReceipt = await callSetCountTx.wait()
+
+    // extract events
+    const [callSetCountResult] = callSetCountReceipt.events.map(
+      (e) => e.event === 'CallResult' && e
+    )[0].args
+
+    // get storage count within ContractCaller contract
+    const storageCount = await contractCaller.count()
+
+    // @notice since callcode use the code from `targetContract` to update `ContractCaller` contract
+    //          => `storageCount` is expected to equal `COUNT_A`
+    expect(storageCount).to.eq(COUNT_A)
+    expect(callSetCountResult).to.be.true
+  })
+
+  it('Should execute delegatecall(g, a, in, insize, out, outsize)', async () => {
+    // prepare transactions
+    const callSetCountTx = await contractCaller.delegateCall(
+      GAS,
+      targetContract.address,
+      setCountEncodedSig
+    )
+
+    // wait for the receipts
+    const callSetCountReceipt = await callSetCountTx.wait()
+
+    // extract events
+    const [callSetCountResult] = callSetCountReceipt.events.map(
+      (e) => e.event === 'CallResult' && e
+    )[0].args
+
+    // get storage count within ContractCaller contract
+    const storageCount = await contractCaller.count()
+
+    // @notice since callcode use the code from `targetContract` to update `ContractCaller` contract
+    //          => `storageCount` is expected to equal `COUNT_A`
+    expect(storageCount).to.eq(COUNT_A)
+    expect(callSetCountResult).to.be.true
+  })
+})