ABI Decode
Let’s see the requirement first.
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// SPDX-License-Identifier: BUSL-1.1
pragma solidity ^0.8.13;
contract Decoder {
/* This exercise assumes you know how abi decoding works.
1. In the `decodeData` function below, write the logic that decodes a `bytes` data, based on the function parameters
2. Return the decoded data
*/
bytes public encoded;
function decodeData(
bytes memory _data
) public pure returns (string memory, uint256) {}
}
Problem Analysis
This problem require us to family the usage of abi.decode, which receive two parameters, first is the encoded data, sencond is the format of the original data.
Coding
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function decodeData(
bytes memory _data
) public pure returns (string memory, uint256) {
return abi.decode(_data, (string, uint256));
}
Test
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➜ Decoder git:(main) ✗ forge test -vvv
[⠊] Compiling...
[⠘] Compiling 19 files with Solc 0.8.25
[⠃] Solc 0.8.25 finished in 763.68ms
Compiler run successful!
Ran 1 test for test/Decoder.t.sol:DecoderTest
[PASS] testDecodedData() (gas: 19759)
Suite result: ok. 1 passed; 0 failed; 0 skipped; finished in 5.17ms (460.83µs CPU time)
Ran 1 test suite in 164.58ms (5.17ms CPU time): 1 tests passed, 0 failed, 0 skipped (1 total tests)
Great, decode executes perfectly.
Reference: Solidity Exercise - ABI Decode
