Implement signature-lint cleanup and fix lint formatting

pkg/extensions/extensions_lint.go

@@ -82,7 +82,6 @@ func containsFiles(root string) bool {
 
 		return nil
 	})
-
 	if walkErr != nil {
 		return false
 	}

pkg/extensions/lint/lint.go

@@ -134,6 +134,7 @@ func (linter *Linter) CheckMandatorySignatures(repo string, manifestDigest godig
 	}
 
 	mandatory := false
+
 	for _, mandatoryRepo := range linter.config.MandatorySignatures {
 		if mandatoryRepo == "*" || mandatoryRepo == "**" || repo == mandatoryRepo {
 			mandatory = true
@@ -228,7 +229,9 @@ func (linter *Linter) hasTrustedSignature(repo string, manifestDigest godigest.D
 	return false, nil
 }
 
-func getSignatureType(descriptor ispec.Descriptor, signatureManifest ispec.Manifest, manifestDigest godigest.Digest) (string, bool) {
+func getSignatureType(descriptor ispec.Descriptor, signatureManifest ispec.Manifest,
+	manifestDigest godigest.Digest,
+) (string, bool) {
 	artifactType := zcommon.GetManifestArtifactType(signatureManifest)
 
 	if signatureManifest.Subject != nil && signatureManifest.Subject.Digest == manifestDigest {

pkg/extensions/lint/lint_signatures_test.go

@@ -113,8 +113,6 @@ func TestMandatorySignaturesFunction(t *testing.T) {
 	})
 
 	for _, wildcard := range []string{"*", "**"} {
-		wildcard := wildcard
-
 		Convey("mandatory signatures check rejects unsigned images for wildcard repository list "+wildcard, t, func() {
 			enable := true
 			lintConfig := &extconf.LintConfig{