AssertionError [ERR_ASSERTION]: Invalid callback object specified

Question

So I was following an Ethereum development course but got stuck into this error while compiling my compile.js file. I have tried this solution also of ReInstalling solidity but it didn't work.

npm solc: AssertionError [ERR_ASSERTION]: Invalid callback specified

Below I have attached my compile.js code.

const path = require('path');
const fs = require('fs-extra');
const solc= require('solc');
const { url } = require('inspector');

const buildPath = path.resolve(__dirname, 'build');

fs.removeSync(buildPath);

const campaignPath= path.resolve(__dirname,'contracts', 'Campaign.sol');
const source=fs.readFileSync(campaignPath,'utf-8');
const output=solc.compile(source,1).contracts;

fs.ensureDirSync(buildPath);

for(let contract in output)
{
    fs.outputJSONSync(
        path.resolve(buildPath,contract + '.json'),
        output[contract]
        );
        
}

And here is the error I am getting.

assert.js:374 
    throw err;
    ^

AssertionError [ERR_ASSERTION]: Invalid callback object specified.
    at runWithCallbacks (D:\react_work\kick_start\node_modules\solc\wrapper.js:97:7)
    at compileStandard (D:\react_work\kick_start\node_modules\solc\wrapper.js:207:14)
    at Object.compileStandardWrapper [as compile] (D:\react_work\kick_start\node_modules\solc\wrapper.js:214:14)
    at Object.<anonymous> (D:\react_work\kick_start\ethereum\compile.js:12:19)
    at Module._compile (internal/modules/cjs/loader.js:956:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:973:10)
    at Module.load (internal/modules/cjs/loader.js:812:32)
    at Function.Module._load (internal/modules/cjs/loader.js:724:14)
    at Function.Module.runMain (internal/modules/cjs/loader.js:1025:10)
    at internal/main/run_main_module.js:17:11 {
  generatedMessage: false,
  code: 'ERR_ASSERTION',
  actual: false,
  expected: true,
  operator: '=='
}

The error is in the line const output=solc.compile(source,1).contracts; — Kshitij Dhyani, Mar 22 '21 at 06:57
this might help : https://ethereum.stackexchange.com/questions/63267/solc-compile-0-5-0-is-not-working-like-0-4-version — Kshitij Dhyani, Mar 22 '21 at 06:58

score 0 · Answer 1 · answered Apr 06 '22 at 13:11

this changes will work:

 const path = require('path');
 const fs = require('fs-extra');
 const solc= require('solc');
 const { url } = require('inspector');

 const buildPath = path.resolve(__dirname, 'build');

 fs.removeSync(buildPath);

 const campaignPath= path.resolve(__dirname,'contracts',   'Campaign.sol');
 const source = fs.readFileSync(campaignPath,'utf-8');
 var input = {
    language: 'Solidity',
    sources: {
             'Campaign.sol': {
              content: source
   }
},
    settings: {
              outputSelection: {
              '*': {
                 '*': ['*']
                  }
               }
      }
};
var output = JSON.parse(solc.compile(JSON.stringify(input)));

AssertionError [ERR_ASSERTION]: Invalid callback object specified

1 Answers1