Truffle error: Error: VM Exception while processing transaction: revert - blockchain

Question

I am using truffle:
truffle(development)> var hw
undefined
truffle(development)> HelloWorld.deployed().then(function(deployed){hw=deployed;});
undefined
truffle(development)> hw.SayHello.call()
i am getting below error in Truffle
***Error: VM Exception while processing transaction: revert
at Object.InvalidResponse (C:\Users\dell\AppData\Roaming\npm\node_modules\truffle\build\cli.bundled.js:41484:16)
at C:\Users\dell\AppData\Roaming\npm\node_modules\truffle\build\cli.bundled.js:328866:36
at C:\Users\dell\AppData\Roaming\npm\node_modules\truffle\build\cli.bundled.js:324536:9
at XMLHttpRequest.request.onreadystatechange (C:\Users\dell\AppData\Roaming\npm\node_modules\truffle\build\cli.bundled.js:327565:7)
at XMLHttpRequestEventTarget.dispatchEvent (C:\Users\dell\AppData\Roaming\npm\node_modules\truffle\build\cli.bundled.js:176407:18)
at XMLHttpRequest._setReadyState (C:\Users\dell\AppData\Roaming\npm\node_modules\truffle\build\cli.bundled.js:176697:12)
at XMLHttpRequest._onHttpResponseEnd (C:\Users\dell\AppData\Roaming\npm\node_modules\truffle\build\cli.bundled.js:176852:12)
at IncomingMessage.<anonymous> (C:\Users\dell\AppData\Roaming\npm\node_modules\truffle\build\cli.bundled.js:176812:24)
at emitNone (events.js:111:20)
at IncomingMessage.emit (events.js:208:7) ***
1) My HelloWorld.sol
`
pragma solidity ^0.4.8;
contract HelloWorld {
function SayHello() public returns (string) {
return ("SomeHello");
}
}
2) My 2_deploy_contracts.js
var ConvertLib = artifacts.require("./ConvertLib.sol");
var MetaCoin = artifacts.require("./MetaCoin.sol");
var HelloWorld = artifacts.require("./HelloWorld.sol");
var second = artifacts.require("./second.sol");
module.exports = function(deployer) {
deployer.deploy(ConvertLib);
deployer.link(ConvertLib, MetaCoin);
deployer.deploy(MetaCoin);
deployer.deploy(HelloWorld);
deployer.deploy(second);
};
3) My truffle.js
module.exports = {
networks: {
development: {
host: "localhost",
port: 8545,
network_id: "*" // Match any network id
}
}
};
Please let me know how can I fix above error ?
`

Answer 1

I just ran your example and it worked fine. The only change I made was I removed the other smart contracts from 2_deploy_contracts that aren't used. Make sure you are running the compile and migrate commands and testrpc is running before starting the truffle console. Also, just in case you're running on Windows, rename truffle.js to truffle-config.js
$ truffle compile
Compiling .\contracts\HelloWorld.sol...
Writing artifacts to .\build\contracts
$ truffle migrate
Using network 'development'.
Running migration: 2_deploy_contracts.js
Deploying HelloWorld...
... 0xef7e895758805a3c3c9aaed7dc7c97fe7b2278b0c0d6ee8105192183a86188c9
HelloWorld: 0x54329ff919efda7920408084590d7480a6c88243
Saving successful migration to network...
... 0x0954625bf66275469c9475ca21f5db20bc4667efb716c5e19bfd98a9553f4a83
Saving artifacts...
$ truffle console
truffle(development)> var hw
undefined
truffle(development)> HelloWorld.deployed().then(function(deployed){hw=deployed;});
undefined
truffle(development)> hw.SayHello.call()
'SomeHello'
truffle(development)>
2_deploy_contracts.js
var HelloWorld = artifacts.require("./HelloWorld.sol");
module.exports = function(deployer) { deployer.deploy(HelloWorld); };