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testingethereumsoliditysmartcontractsremix

How to test the Solidity-By-Example Mapping smart contract in Remix?

I want to test the following code in Remix. But what is the procedure?

What do I put in the input field for the function labeled set?

Mapping.sol
// https://solidity-by-example.org/mapping
// Mapping
// Maps are created with the syntax mapping(keyType => valueType).
// The keyType can be any built-in value type, bytes, string, or any contract.
// valueType can be any type including another mapping or an array.
// Mappings are not iterable.

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.13;

contract Mapping {
    // Mapping from address to uint
    mapping(address => uint) public myMap;

    function get(address _addr) public view returns (uint) {
        // Mapping always returns a value.
        // If the value was never set, it will return the default value.
        return myMap[_addr];
    }

    function set(address _addr, uint _i) public {
        // Update the value at this address
        myMap[_addr] = _i;
    }

    function remove(address _addr) public {
        // Reset the value to the default value.
        delete myMap[_addr];
    }
}

contract NestedMapping {
    // Nested mapping (mapping from address to another mapping)
    mapping(address => mapping(uint => bool)) public nested;

    function get(address _addr1, uint _i) public view returns (bool) {
        // You can get values from a nested mapping
        // even when it is not initialized
        return nested[_addr1][_i];
    }

    function set(
        address _addr1,
        uint _i,
        bool _boo
    ) public {
        nested[_addr1][_i] = _boo;
    }

    function remove(address _addr1, uint _i) public {
        delete nested[_addr1][_i];
    }
}

This code came from Solidity by Example.

When I implement it on Remix, I get the following screen.

enter image description here

At this point, to test it, I think I need to map an address to a uint256, so I enter the following in the field next to the set button:

["0xcf646ed6e21fd0756ec45a6be5e1057fc24a1b8308175ff0b9f97f565b594eb3", 7439]

The value of the address was a randomly generated hash (I suspect the random hash might be a problem?)

enter image description here

I expect to see the set function render the value 7439. But, instead, it throws the following error:

transact to Mapping.set errored: Error encoding arguments: Error: invalid address (argument="address", value=["0xcf646ed6e21fd0756ec45a6be5e1057fc24a1b8308175ff0b9f97f565b594eb3",7439], code=INVALID_ARGUMENT, version=address/5.5.0) (argument=null, value=["0xcf646ed6e21fd0756ec45a6be5e1057fc24a1b8308175ff0b9f97f565b594eb3",7439], code=INVALID_ARGUMENT, version=abi/5.5.0)

What am I doing wrong?

Solution

  • You have generated a random SHA-256 that is of the format of a valid address, but it doesn't exist on the Remix's browser-based (Javascript VM) chain as any account. If it does, you might be just lucky.

    If you want to use valid addresses that do exist on the browser-based VM chain, copy and use the addresses in the account section.

    Account section