with lazy resolve

Signed-off-by: Avi Deitcher <avi@deitcher.net>

pkg/v1/layout/write.go

@@ -173,11 +173,7 @@ func (l Path) replaceDescriptor(append mutate.Appendable, matcher match.Matcher,
 		Add:        append,
 		Descriptor: *desc,
 	}
-	ii, err = mutate.RemoveManifests(ii, matcher)
-	if err != nil {
-		return err
-	}
-	ii = mutate.AppendManifests(ii, add)
+	ii = mutate.AppendManifests(mutate.RemoveManifests(ii, matcher), add)
 
 	index, err := ii.IndexManifest()
 	if err != nil {
@@ -198,10 +194,7 @@ func (l Path) RemoveDescriptors(matcher match.Matcher) error {
 	if err != nil {
 		return err
 	}
-	ii, err = mutate.RemoveManifests(ii, matcher)
-	if err != nil {
-		return err
-	}
+	ii = mutate.RemoveManifests(ii, matcher)
 
 	index, err := ii.IndexManifest()
 	if err != nil {

pkg/v1/mutate/index.go

@@ -20,6 +20,7 @@ import (
 
 	"github.com/google/go-containerregistry/pkg/logs"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
+	"github.com/google/go-containerregistry/pkg/v1/match"
 	"github.com/google/go-containerregistry/pkg/v1/partial"
 	"github.com/google/go-containerregistry/pkg/v1/types"
 )
@@ -58,6 +59,8 @@ type index struct {
 	adds []IndexAddendum
 	// replaces are applied before adds
 	replaces []v1.Descriptor
+	// removes are removed after replaces and before adds
+	removes []match.Matcher
 
 	computed  bool
 	manifest  *v1.IndexManifest
@@ -96,6 +99,16 @@ func (i *index) compute() error {
 		manifests = i.replaces
 	}
 
+	var cleanedManifests []v1.Descriptor
+	for _, r := range i.removes {
+		for _, m := range manifests {
+			if !r(m) {
+				cleanedManifests = append(cleanedManifests, m)
+			}
+		}
+		manifests = cleanedManifests
+	}
+
 	for _, add := range i.adds {
 		desc, err := computeDescriptor(add)
 		if err != nil {

pkg/v1/mutate/mutate.go

@@ -94,23 +94,11 @@ func AppendManifests(base v1.ImageIndex, adds ...IndexAddendum) v1.ImageIndex {
 }
 
 // RemoveManifests removes any descriptors that match the match.Matcher.
-func RemoveManifests(base v1.ImageIndex, matcher match.Matcher) (v1.ImageIndex, error) {
-	ii, err := base.IndexManifest()
-	if err != nil {
-		return base, err
-	}
-
-	// create a list without any existing ones
-	manifests := []v1.Descriptor{}
-	for _, manifest := range ii.Manifests {
-		if !matcher(manifest) {
-			manifests = append(manifests, manifest)
-		}
-	}
+func RemoveManifests(base v1.ImageIndex, matcher match.Matcher) v1.ImageIndex {
 	return &index{
-		base:     base,
-		replaces: manifests,
-	}, nil
+		base:    base,
+		removes: []match.Matcher{matcher},
+	}
 }
 
 // Config mutates the provided v1.Image to have the provided v1.Config

pkg/v1/mutate/mutate_test.go

@@ -503,10 +503,7 @@ func TestRemoveManifests(t *testing.T) {
 			t.Fatalf("mismatched manifests on setup, had %d, expected %d", len(manifest.Manifests), count)
 		}
 		digest := manifest.Manifests[i].Digest
-		ii, err = mutate.RemoveManifests(ii, match.Digests(digest))
-		if err != nil {
-			t.Fatal(err)
-		}
+		ii = mutate.RemoveManifests(ii, match.Digests(digest))
 		manifest, err = ii.IndexManifest()
 		if err != nil {
 			t.Fatal(err)