sol_callfunc.solidity

pragma solidity ^0.5.0;

interface Callable {
    function test() external returns (address);
}

// user: 0xca35b7d915458ef540ade6068dfe2f44e8fa733c
// TestAddress: 0xbbf289d846208c16edc8474705c748aff07732db
// CallAddress: 0x692a70d2e424a56d2c6c27aa97d1a86395877b3a
// user call Test.callTest(CallAddress)
// msg.sender == TestAddress
contract Test {
    constructor() public {}
    
    function callTest(address a) public returns (address) {
        return Callable(a).test();
    }
}

contract Call {
    uint256 public nonce;
    constructor() public {}
    
    function test() external returns (address) {
        nonce++;
        return msg.sender;
    }
}