Truffle Flattener concats solidity files from Truffle and Buidler projects with all of their dependencies.
This tool helps you to verify contracts developed with Truffle and Buidler on Etherscan, or debugging them on Remix, by merging your files and their dependencies in the right order.
If you are still using Truffle, we recommend you try Buidler, our Ethereum development environment, which is much faster and flexible.
npm install truffle-flattener -g
Just intall it with npm in your truffle project and run
truffle-flattener <solidity-files>.
Aliased imports (eg: import {symbol1 as alias, symbol2} from "filename";) are
not supported by truffle-flattener.