I am trying to run some basic test w/ my contract, written with Truffle's Solidity tests (tests written in Solidity).

When runninng truffle test, I get

Error: VM Exception while processing transaction: out of gas

Note: This is caused by the contract constructor new ..., which is indeed doing a lot of things. And I can't break anything down in my code.

Is there any way to get this working with a test written in Solidity? Is there a way to configure the amount of gas the test contract has available?



Actually I figured out changing the gas config value in truffle.js does have an effect. Yet, I am hitting now another roadblock

Error: Error: Exceeds block gas limit

I guess that I have no other choice than optimising the deployment (thus, the constructor) of my contract so as to make it lighter?


3 Answers 3


I ran into the same issue today - but for me the issue was, that my test-file.sol was seemingly too large. So I split up my tests into two files, and all the tests ran just fine again.

It probably makes sense anyways to structure test-files in multiple smaller suites than one big file that you'd have to scroll through.


Add gas: 350000 to your truffle.js file, example of mine below

module.exports = {
  networks: {
     development: {
       host: "localhost",
       port: 8545,
       network_id: "*", // Match any network id
       gas: 3500000
   mocha: {
    useColors: true

The new version of truffle, version 4 at this moment has added a gas check to tests. so this is needed now.


Probably should make it lighter.

If you're using TestRPC or a private chain, you can set the gaslimit, but it's a network property. I would reserve that method for troubleshooting i.e. to confirm what you're dealing with. Note that out-of-gas sometimes happens when the contract throws on purpose, so it can be misleading.

If you don't find a way to operate within a budget you're probably setting yourself up for disappointment when you try to deploy to the live network.

Hope it helps.

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