Add slices to buildpack.toml

builder.go

@@ -74,6 +74,7 @@ func (b *Builder) Build() (*platform.BuildMetadata, error) {
 		if err != nil {
 			return nil, err
 		}
+		slices = append(slices, bpTOML.Slices...)
 
 		b.Logger.Debug("Finding plan")
 		inputs.Plan = filteredPlan.Find(buildpack.KindBuildpack, bp.ID)

builder_test.go

@@ -874,7 +874,12 @@ func testBuilder(t *testing.T, when spec.G, it spec.S) {
 
 			when("slices", func() {
 				it("aggregates slices from each buildpack", func() {
-					bpA := &buildpack.BpDescriptor{Buildpack: buildpack.BpInfo{BaseInfo: buildpack.BaseInfo{ID: "A", Version: "v1"}}}
+					bpA := &buildpack.BpDescriptor{
+						Buildpack: buildpack.BpInfo{BaseInfo: buildpack.BaseInfo{ID: "A", Version: "v1"}},
+						Slices: []layers.Slice{
+							{Paths: []string{"static-path-from-buildpack-toml"}},
+						},
+					}
 					dirStore.EXPECT().LookupBp("A", "v1").Return(bpA, nil)
 					executor.EXPECT().Build(*bpA, gomock.Any(), gomock.Any()).Return(buildpack.BuildOutputs{
 						Slices: []layers.Slice{
@@ -895,6 +900,7 @@ func testBuilder(t *testing.T, when spec.G, it spec.S) {
 					metadata, err := builder.Build()
 					h.AssertNil(t, err)
 					if s := cmp.Diff(metadata.Slices, []layers.Slice{
+						{Paths: []string{"static-path-from-buildpack-toml"}},
 						{Paths: []string{"some-bpA-path", "some-other-bpA-path"}},
 						{Paths: []string{"duplicate-path"}},
 						{Paths: []string{"extra-path"}},

buildpack/bp_descriptor.go

@@ -7,6 +7,8 @@ import (
 	"os"
 	"path/filepath"
 
+	"github.com/buildpacks/lifecycle/layers"
+
 	"github.com/BurntSushi/toml"
 )
 
@@ -17,7 +19,7 @@ type BpDescriptor struct {
 	WithRootDir string           `toml:"-"`
 	Targets     []TargetMetadata `toml:"targets"`
 	Stacks      []StackMetadata  `tome:"stacks"` // just for backwards compat so we can check if it's the bionic stack, which we translate to a target
-
+	Slices      []layers.Slice   `toml:"slices"`
 }
 
 type StackMetadata struct {