DeclarationError: Function with same name and parameter types defined twice.

[DamirS09]

Hi, I get an error with np hardhat coverage, I also used 0.7.2

[anuprshetty]

I got the same error. Anyone please help.

I have flattened a solidity file in hardhat project.
pragma solidity ^0.8.0;
hardhat version: 2.14.0
solidity-coverage: v0.8.2

Ran the below command:
npx hardhat coverage

It is giving the error same as in the screenshot #769 (comment)

@cgewecke and @area please help on this. The tool is really good. But just stuck on this error.

[cgewecke]

Does anyone have reproduction steps for this?

[DamirS09]

Does anyone have reproduction steps for this?

the problem with redefinition was not working with virtual and ovveride

[cgewecke]

@Bubble7777 So it's still an issue? Could you give a simple example to help me understand what's going wrong?

[anuprshetty]

I understood the root cause.
This issue caused when you have diamond inheritance dependency for your contract and you have flattened the file.

Example:
D
/ \
B C
\ /
A

Here my contract A inherits contracts B and C. Internally lets say B and C inherits same contract D.
With this setup, flatten the file. So all contracts A, B, C, and D are placed in the same file.

Now if you run solidity-coverage on this file, this error occurs.

[cgewecke]

Have tried to reproduce this in #836 following the advice the comment above but ... no luck. Everything compiles. If anyone can provide a simple reproduction case for this to investigate, will re-open and take another look.

[tanujdamani]

Was able to replicate this problem for a basic contract and gives the same error when running coverage on the flattened file.

Here is how to replicate:

All files can be found here: https://gist.github.com/tanujdamani/56a4fd8460ce4546913eb715d9366dc3

1. Created a simple ERC721 contract with AccessControl using the OZ Wizard. (Added Strings and the tokenURI override function.)
2. This is the contract simpleContract.sol
3. This file was flattened using hardhat. npx hardhat flatten contracts/simpleContract.sol > simplyFlat.sol
4. This is the flattened contract simplyFlat.sol
5. Moved the new contract simplyFlat.sol to the contracts/ folder.
6. Then checked coverage by running this command: npx hardhat coverage
7. This gave the following errors.
8. Running the command with --show-stack-traces additionally returned the following lines:

HardhatPluginError: HardhatError: HH600: Compilation failed
    at SimpleTaskDefinition.action (/Users/tj/Developer/simpleContract/node_modules/solidity-coverage/plugins/hardhat.plugin.js:274:35)
    at Environment._runTaskDefinition (/Users/tj/Developer/simpleContract/node_modules/hardhat/src/internal/core/runtime-environment.ts:358:14)
    at Environment.run (/Users/tj/Developer/simpleContract/node_modules/hardhat/src/internal/core/runtime-environment.ts:191:14)
    at main (/Users/tj/Developer/simpleContract/node_modules/hardhat/src/internal/cli/cli.ts:323:7)

Additional Information:

• hardhat: v2.20.0
• @openzeppelin/contracts: v4.9.5
• @nomicfoundation/hardhat-toolbox: v4.0.0

Edited the comment and moved all the code to a gist.

[cgewecke]

@tanujdamani Nice work, thank you. Will take a look...