Support multiple simultaneous solc versions

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tags: compiler, solidity-versioning

• I’ve asked for help in the Truffle Gitter before filing this issue.

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Issue

In contracts folder, I have old contracts in 0.4 version of solidity and new contracts in 0.5 version. I would like to compile them in the same project but in truffle-config.js, I can only specify one version of solc.

Steps to Reproduce

In contracts folder, create a contract A in 0.4 and another one, contract B, in 0.5

Expected Behavior

I would like truffle compile to work

Actual Results

If I compile with solc 0.4.24, contract B in 0.5 fails to compile If I compile with solc 0.5.0, contract A in 0.4 fails to compile

Environment

• Operating System: ubuntu 18.10
• Ethereum client: ganache
• Truffle version (truffle version): 5.0.16
• node version (node --version): 11.9.0
• npm version (npm --version): 6.5.0

[gnidan]

Moving this to our backlog. I want it!

[amkCha]

Hi @CruzMolina, thank you very much for you help !

I had to change two more things in old contracts in 0.4 for them to work

• SyntaxError: Functions are not allowed to have the same name as the contract. If you intend this to be a constructor, use “constructor(…) { … }” to define it
• Event invocations have to be prefixed by “emit”

If you see a better workaround, I’d be happy to hear about it

Else, after adding ‘emit’ and changing the function naming, it’s compiling 😃