strict mode does not fail for "cannot find package" error

[ijc]

I noticed that a project (moby/buildkit as it happens) was missing a dependency (you can see it here). I patched the check (./hack/validate-vendor and hack/dockerfiles/vendor.Dockerfile) thinking it would cause the check to fail but it did not:

$ git diff
diff --git a/hack/dockerfiles/vendor.Dockerfile b/hack/dockerfiles/vendor.Dockerfile
index 64cd656..ac82dfe 100644
--- a/hack/dockerfiles/vendor.Dockerfile
+++ b/hack/dockerfiles/vendor.Dockerfile
@@ -7,4 +7,4 @@ RUN go get -d github.com/LK4D4/vndr \
        && go install ./
 WORKDIR /go/src/github.com/moby/buildkit
 COPY . .
-RUN vndr --verbose
\ No newline at end of file
+RUN vndr --verbose --strict
[...]
$ ./hack/validate-vendor 
[...]
+ docker build --build-arg VNDR_VERSION=48ac2669d9d1bcacd3163650ef911edca2ec3b42 --iidfile /tmp/docker-iidfile.9obqMoTlAJ -f ./hack/dockerfiles/vendor.Dockerfile --force-rm .
[...]Step 7/7 : RUN vndr --verbose --strict
 ---> Running in 1c252b10149d
2018/03/08 14:26:15 Collecting initial packages
2018/03/08 14:26:15 Download dependencies
[...]
2018/03/08 14:27:11 Dependencies downloaded. Download time: 55.205977209s
2018/03/08 14:27:11 Collecting all dependencies
2018/03/08 14:27:13 	WARNING(verbose) github.com/tonistiigi/llb-gobuild: cannot find package "github.com/tonistiigi/llb-gobuild" in any of:
	/go/src/github.com/moby/buildkit/vendor/github.com/tonistiigi/llb-gobuild (vendor tree)
	/go/src/github.com/moby/buildkit/vendor/github.com/tonistiigi/llb-gobuild
	/usr/local/go/src/github.com/tonistiigi/llb-gobuild (from $GOROOT)
	/go/src/github.com/tonistiigi/llb-gobuild (from $GOPATH)
2018/03/08 14:27:14 Clean vendor dir from unused packages
2018/03/08 14:27:14 Success
2018/03/08 14:27:14 Running time: 59.498826306s
Removing intermediate container 1c252b10149d
 ---> cf2f4a83aad9
Successfully built cf2f4a83aad9
++ cat /tmp/docker-iidfile.9obqMoTlAJ
+ iid=sha256:cf2f4a83aad9c24e1e16e2ff5dc6fde8265d4872dbe1f6f91cc12bb7abded0e1
++ docker run sha256:cf2f4a83aad9c24e1e16e2ff5dc6fde8265d4872dbe1f6f91cc12bb7abded0e1 git status --porcelain -- vendor
+ diffs=
+ '[' '' ']'
+ echo 'Congratulations! All vendoring changes are done the right way.'
Congratulations! All vendoring changes are done the right way.
+ rm -f /tmp/docker-iidfile.9obqMoTlAJ

I think this should have failed.

The above is with 48ac2669d9d1bcacd3163650ef911edca2ec3b42 but I have also reproduced with b57c5799efd5ed743f347a025482babf01ba963e which is the most recent master.

In fact with the most recent master it seems the WARNING has gone, even though llb-gobuild is still used -- the usage is in a example command (so a main package, but a few levels down in the source tree) so perhaps that got missed?

[ijc]

In fact with the most recent master it seems the WARNING has gone, even though llb-gobuild is still used -- the usage is in a example command (so a main package, but a few levels down in the source tree) so perhaps that got missed?

Ah, the file has // +build ignore so perhaps this is a deliberate fix.

[ijc]

Having noticed the // +build ignore I think this is now only relevant as it relates to #63.