improve doc comments

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

syft/presenter/json/artifact.go

@@ -34,7 +34,6 @@ type artifactMetadataUnpacker struct {
 }
 
 func NewArtifact(p *pkg.Package) (Artifact, error) {
-
 	return Artifact{
 		artifactBasicMetadata: artifactBasicMetadata{
 			Name:      p.Name,
@@ -67,6 +66,7 @@ func (a Artifact) ToPackage() pkg.Package {
 	}
 }
 
+// nolint:funlen
 func (a *Artifact) UnmarshalJSON(b []byte) error {
 	var basic artifactBasicMetadata
 	if err := json.Unmarshal(b, &basic); err != nil {
@@ -128,7 +128,6 @@ func (a *Artifact) UnmarshalJSON(b []byte) error {
 		// there may be packages with no metadata, which is OK
 	default:
 		return fmt.Errorf("unsupported package metadata type: %+v", a.MetadataType)
-
 	}
 
 	return nil

syft/presenter/json/source.go

@@ -55,7 +55,6 @@ func (s *Source) UnmarshalJSON(b []byte) error {
 		s.Target = payload
 	default:
 		return fmt.Errorf("unsupported package metadata type: %+v", s.Type)
-
 	}
 
 	return nil

syft/presenter/json/test-fixtures/snapshot/TestJsonDirsPresenter.golden

@@ -14,7 +14,7 @@
     "MIT"
    ],
    "language": "python",
-   "metadataType": "python-package-metadata",
+   "metadataType": "PythonPackageMetadata",
    "metadata": {
     "name": "package-1",
     "version": "1.0.1",
@@ -37,7 +37,7 @@
    ],
    "licenses": null,
    "language": "",
-   "metadataType": "dpkg-metadata",
+   "metadataType": "DpkgMetadata",
    "metadata": {
     "package": "package-2",
     "source": "",

syft/presenter/json/test-fixtures/snapshot/TestJsonImgsPresenter.golden

@@ -15,7 +15,7 @@
     "MIT"
    ],
    "language": "python",
-   "metadataType": "python-package-metadata",
+   "metadataType": "PythonPackageMetadata",
    "metadata": {
     "name": "package-1",
     "version": "1.0.1",
@@ -39,7 +39,7 @@
    ],
    "licenses": null,
    "language": "",
-   "metadataType": "dpkg-metadata",
+   "metadataType": "DpkgMetadata",
    "metadata": {
     "package": "package-2",
     "source": "",

syft/presenter/text/presenter.go

@@ -10,11 +10,13 @@ import (
 	"github.com/anchore/syft/syft/source"
 )
 
+// Presenter is a human-friendly text presenter to represent package and source data.
 type Presenter struct {
 	catalog     *pkg.Catalog
 	srcMetadata source.Metadata
 }
 
+// NewPresenter creates a new presenter for the given set of catalog and image data.
 func NewPresenter(catalog *pkg.Catalog, srcMetadata source.Metadata) *Presenter {
 	return &Presenter{
 		catalog:     catalog,