fuzzing rig interferes with go get installation

[cortesi]

This command succeeds:

go get -u mvdan.cc/sh/v3@b1d056c32fce2c42d12f9342a454d8eb0d069625

This command, for the subsequent commit that revives the fuzzing rig, fails:

go get -u mvdan.cc/sh/v3@31a35be0acb24a89b8dc91f60f11a7d1fdcf3957               

mvdan.cc/sh/v3: no Go source files
package mvdan.cc/sh/v3: build constraints exclude all Go files in /home/cortesi/go/pkg/mod/mvdan.cc/sh/v3@v3.3.0-0.dev.0.20201102111809-31a35be0acb2

I see the same error for master.

I haven't had time to dig into this completely, but the issue is related to the +build gofuzz directive in the fuzz.go file, and might be fixed by this recent commit in the Go project:

https://go-review.googlesource.com/c/go/+/289769/

See further discussion here:

golang/go#29268 (comment)

[mvdan]

You should be using go get -d to update dependencies. I believe -d will become a default in a future Go release. Otherwise, you're building the package at that path, which rarely makes sense; you could just use go build or go install for that.

I guess I could move the fuzz files elsewhere, like in the syntax package, but I still reckon that this is not a bug :)

[cortesi]

Ah, my apologies - I was sure I checked this. I see -d also outputs the "no Go source files" warning, so I must have assumed the command had failed when it had actually updated the module. I guess this will become nicer in a future release of Go. This solves my problem, so I'll close this issue.