github.com/chain4travel/go-ethereum@v1.9.7/tests/solidity/contracts/Migrations.sol (about)

     1  pragma solidity >=0.4.21 <0.6.0;
     2  
     3  contract Migrations {
     4    address public owner;
     5    uint public last_completed_migration;
     6  
     7    constructor() public {
     8      owner = msg.sender;
     9    }
    10  
    11    modifier restricted() {
    12      if (msg.sender == owner) _;
    13    }
    14  
    15    function setCompleted(uint completed) public restricted {
    16      last_completed_migration = completed;
    17    }
    18  
    19    function upgrade(address new_address) public restricted {
    20      Migrations upgraded = Migrations(new_address);
    21      upgraded.setCompleted(last_completed_migration);
    22    }
    23  }