Go modules and forks

I'm tinkering with a Go project ( let's call it foobar ), which has a dependency upon yet another Go project ( let's call it snafu )  in the same organisation.

For the moment, I've got a fork of snafu in my own org - david-hay - and wanted to update go.mod in the foobar project to leverage it.

I knew I had to update go.mod either manually or use go mod edit --replace source=target but couldn't get past the exception: -

go: -replace=github.com/org/snafu=github.com/david-hay/snafu: unversioned new path must be local directory

It turned out, as ever, that I was holding it wrong ...

I needed to explicitly provide a "version" - in this context, that was a branch e.g. main at which to point the target during go mod edit --replace like this: -

go mod edit --replace github.com/org/snafu=github.com/david-hay/snafu@main

In other words, the right-hand side of the --replace directive needed to include four things: -

- domain e.g. github.com

- organization e.g. david-hay

- project/repo e.g. snafu

- branch e.g. main

like this: -

...

replace github.com/org/snafu => github.com/david-hay/snafu main

When I then ran go mod tidy, this went off to GitHub and pulled down the latest release from that branch in my fork: -

go: downloading github.com/david-hay/snafu v1.11.39-0.20230116121922-46267d910e38

and updated go.mod with: -

replace github.com/org/snafu => github.com/david-hay/snafu v1.11.39-0.20230116121922-46267d910e38

In other words, it replaced the branch with the release ... which is nice

With thanks to this: -

Pointing to a fork of a Go module