moby/layer/empty_test.go
Sebastiaan van Stijn a0230f3d9a
remove unneeded "digest" alias for "go-digest"
I think this was there for historic reasons (may have been goimports expected
this, and we used to have a linter that wanted it), but it's not needed, so
let's remove it (to make my IDE less complaining about unneeded aliases).

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2022-03-04 14:49:42 +01:00

52 lines
1.2 KiB
Go

package layer // import "github.com/docker/docker/layer"
import (
"io"
"testing"
"github.com/opencontainers/go-digest"
)
func TestEmptyLayer(t *testing.T) {
if EmptyLayer.ChainID() != ChainID(DigestSHA256EmptyTar) {
t.Fatal("wrong ChainID for empty layer")
}
if EmptyLayer.DiffID() != DigestSHA256EmptyTar {
t.Fatal("wrong DiffID for empty layer")
}
if EmptyLayer.Parent() != nil {
t.Fatal("expected no parent for empty layer")
}
if size := EmptyLayer.Size(); size != 0 {
t.Fatal("expected zero size for empty layer")
}
if diffSize := EmptyLayer.DiffSize(); diffSize != 0 {
t.Fatal("expected zero diffsize for empty layer")
}
meta, err := EmptyLayer.Metadata()
if len(meta) != 0 || err != nil {
t.Fatal("expected zero length metadata for empty layer")
}
tarStream, err := EmptyLayer.TarStream()
if err != nil {
t.Fatalf("error streaming tar for empty layer: %v", err)
}
digester := digest.Canonical.Digester()
_, err = io.Copy(digester.Hash(), tarStream)
if err != nil {
t.Fatalf("error hashing empty tar layer: %v", err)
}
if digester.Digest() != digest.Digest(DigestSHA256EmptyTar) {
t.Fatal("empty layer tar stream hashes to wrong value")
}
}