Ambiguous import

[joshklop]

Hi! I'm importing github.com/ethereum/go-ethereum/core/types, which depends on btcd. When I run go mod tidy, I get the following error:

github.com/filecoin-project/bacalhau/pkg/storage/ethblock imports
	github.com/ethereum/go-ethereum/core/types imports
	github.com/ethereum/go-ethereum/crypto imports
	github.com/btcsuite/btcd/btcec/v2/ecdsa tested by
	github.com/btcsuite/btcd/btcec/v2/ecdsa.test imports
	github.com/btcsuite/btcd/chaincfg/chainhash: ambiguous import: found package github.com/btcsuite/btcd/chaincfg/chainhash in multiple modules:
	github.com/btcsuite/btcd v0.22.0-beta (/home/user/.go/pkg/mod/github.com/btcsuite/[email protected]/chaincfg/chainhash)
	github.com/btcsuite/btcd/chaincfg/chainhash v1.0.1 (/home/user/.go/pkg/mod/github.com/btcsuite/btcd/chaincfg/[email protected])

Even after reading through a number of issues (#1839, here, here), I have been unable to resolve the issue.

I am on the latest version of go-ethereum. If I create a nearly empty go module and import the github.com/ethereum/go-ethereum/core/types package, I do not get this issue. Any suggestions/pointers would be much appreciated.

[chappjc]

Can you link to the branch you are working on and/or the go.mod?

[joshklop]

Thanks for the prompt response! Branch, go.mod

[chappjc]

Nothing stands out, hmm. Give go get -d github.com/btcsuite/btcd/chaincfg/[email protected] a shot maybe.

[joshklop]

That worked! It appears I have some gaps in my understanding of go modules. Where is the -d flag documented?

[chappjc]

That worked! It appears I have some gaps in my understanding of go modules. Where is the -d flag documented?

It's not you. Go modules are a confusing nightmare. I think there's a go tool bug you were hitting in this case. The btcec/v2 module clearly requires a specific chainhash module, and your project has no direct or transitive requires on btcd (that I can see), so it shouldn't have barfed like this.