"unresolved libraries" error in Truffle migrations

[cgewecke]

Opening and closing in case someone runs into this...

At synthetix 452, libraries were not linking as expected. Their migrations fn looked like:

module.export = async function(deployer, network, accounts){
  await deployer.deploy(LibA)

  deployer.link(LibA, ContractA); // Needs to be awaited
  await deployer.deploy(ContractA); 

  ...
}

For unknowns reasons when Truffle runs this in the plugin context the link method (which is technically async) needs to be awaited, otherwise there's a race-condition failure. Basically, this fixes...

await deployer.link(LibA, ContractA)

[Destiner]

Error message to make this searchable:

Error: while migrating X: X contains unresolved libraries. You must deploy and link the following libraries before you can deploy a new version of X: A, B, C