Unexport types and functions cataloger packages (#2530)

* unexport as many types and functions from cataloger packages as possible

Signed-off-by: Alex Goodman <wagoodman@users.noreply.github.com>

* capture type and signature information in convention test

Signed-off-by: Alex Goodman <wagoodman@users.noreply.github.com>

* check that we return pkg.Cataloger from constructors

Signed-off-by: Alex Goodman <wagoodman@users.noreply.github.com>

---------

Signed-off-by: Alex Goodman <wagoodman@users.noreply.github.com>

syft/pkg/cataloger/java/cataloger.go

@@ -9,7 +9,7 @@ import (
 )
 
 // NewArchiveCataloger returns a new Java archive cataloger object for detecting packages with archives (jar, war, ear, par, sar, jpi, hpi, and native-image formats)
-func NewArchiveCataloger(cfg ArchiveCatalogerConfig) *generic.Cataloger {
+func NewArchiveCataloger(cfg ArchiveCatalogerConfig) pkg.Cataloger {
 	gap := newGenericArchiveParserAdapter(cfg)
 
 	c := generic.NewCataloger("java-archive-cataloger").

syft/pkg/cataloger/java/graalvm_native_image_cataloger.go

@@ -92,7 +92,7 @@ type nativeImagePE struct {
 	header        exportPrefixPE
 }
 
-type NativeImageCataloger struct{}
+type nativeImageCataloger struct{}
 
 const nativeImageCatalogerName = "graalvm-native-image-cataloger"
 const nativeImageSbomSymbol = "sbom"
@@ -104,11 +104,11 @@ const nativeImageMissingExportedDataDirectoryError = "exported data directory is
 
 // NewNativeImageCataloger returns a new Native Image cataloger object.
 func NewNativeImageCataloger() pkg.Cataloger {
-	return &NativeImageCataloger{}
+	return &nativeImageCataloger{}
 }
 
 // Name returns a string that uniquely describes a native image cataloger
-func (c *NativeImageCataloger) Name() string {
+func (c *nativeImageCataloger) Name() string {
 	return nativeImageCatalogerName
 }
 
@@ -571,7 +571,7 @@ func fetchPkgs(reader unionreader.UnionReader, filename string) []pkg.Package {
 }
 
 // Catalog attempts to find any native image executables reachable from a resolver.
-func (c *NativeImageCataloger) Catalog(_ context.Context, resolver file.Resolver) ([]pkg.Package, []artifact.Relationship, error) {
+func (c *nativeImageCataloger) Catalog(_ context.Context, resolver file.Resolver) ([]pkg.Package, []artifact.Relationship, error) {
 	var pkgs []pkg.Package
 	fileMatches, err := resolver.FilesByMIMEType(internal.ExecutableMIMETypeSet.List()...)
 	if err != nil {

syft/pkg/cataloger/java/parse_gradle_lockfile.go

@@ -13,8 +13,8 @@ import (
 
 const gradleLockfileGlob = "**/gradle.lockfile*"
 
-// LockfileDependency represents a single dependency in the gradle.lockfile file
-type LockfileDependency struct {
+// lockfileDependency represents a single dependency in the gradle.lockfile file
+type lockfileDependency struct {
 	Group   string
 	Name    string
 	Version string
@@ -27,7 +27,7 @@ func parseGradleLockfile(_ context.Context, _ file.Resolver, _ *generic.Environm
 	scanner := bufio.NewScanner(reader)
 
 	// Create slices to hold the dependencies and plugins
-	dependencies := []LockfileDependency{}
+	dependencies := []lockfileDependency{}
 
 	// Loop over all lines in the file
 	for scanner.Scan() {
@@ -43,7 +43,7 @@ func parseGradleLockfile(_ context.Context, _ file.Resolver, _ *generic.Environm
 		// we have a version directly specified
 		if len(parts) == 3 {
 			// Create a new Dependency struct and add it to the dependencies slice
-			dep := LockfileDependency{Group: parts[0], Name: parts[1], Version: parts[2]}
+			dep := lockfileDependency{Group: parts[0], Name: parts[1], Version: parts[2]}
 			dependencies = append(dependencies, dep)
 		}
 	}