godep save inconsistent between platforms

[jzelinskie]

I have some code (closed source 😿) that has a dependency using the // +build construct to variably include some of their source files. This leads to dependencies in those files from being excluded if godep save is ran on a platform that does not require those files.

If I godep save on Mac, it'll build and run perfectly fine on Mac, but if I take that codebase and try and build it on Linux, the Godeps directory will be missing dependencies and will fail to compile. I'm currently resolving this by only doing godep save/godep update on Linux, but it is not a long-term solution as all of our developers are primarily working on Mac.

[rnapier]

I've been playing with ways to address this. It's possible to pass -tags to the "go list" command, so you could pass the tags "darwin linux". That works ok as long as nothing uses the ! syntax. So if you had a !linux, it would not include it even though you'd want it. That's causing me trouble on Windows because some things in the standard library are defined as !windows rather than an explicit list of everything else.

The other option is to run LoadPackages once for each desired tag and then merge the results. That's probably the way it needs to work, but the code is more complicated.

[jzelinskie]

Sorry that I didn't post this earlier: the workaround that we've been using is to just use GOOS=linux go get -d ./... for getting dependencies. We're just lucky that there isn't anything excluded that OSX requires.

[phinze]

Hey folks, we just switched to Godep over in hashicorp/terraform and we're running into this problem.

We build Terraform for several platforms and we're running into problems trying to vendor the superset of dependencies without constantly fighting diffs or manually editing metadata.

Have any of you come up with methods for addressing this issue?

The other option is to run LoadPackages once for each desired tag and then merge the results. That's probably the way it needs to work, but the code is more complicated.

We might investigate this as a PR if it sounds like a valid approach to everybody.

[freeformz]

What version of godep are you using? At this point godep no longer uses go list to resolve any dependencies and processes files/deps for all files except those that include the appengine or ignore build tags.

[phinze]

Hi @freeformz - thanks for the tip! Looks like we were indeed running an older version of godep.

Did a fresh go get -u and this seems to be resolved w/ the newer version.

hashicorp/terraform#4957 looks to have the proper superset dependency list

Since everything seems to be working I believe this (and the linked #174) can be closed. 👍

[freeformz]

Great! Thanks. Closing. For anyone else on this ticket please re-open / post a follow up if, after updating, things aren't working for you.

[jzelinskie]

@freeformz, I've encountered a similar issue on v52 when recently vendoring. I need to double check to see if it is also caused by +build or something else, but I did not have all the proper dependencies.

[freeformz]

@jzelinskie If so please file that as a separate issue unless someone else has already done so. ;-)