Add test extractor.

extractor/list/list.go

@@ -20,7 +20,6 @@ import (
 	"os"
 	"strings"
 
-	"github.com/google/osv-scanner/pkg/lockfile"
 	"github.com/google/osv-scalibr/extractor"
 	"github.com/google/osv-scalibr/extractor/language/dotnet/packageslockjson"
 	"github.com/google/osv-scalibr/extractor/language/golang/gobinary"
@@ -34,10 +33,12 @@ import (
 	"github.com/google/osv-scalibr/extractor/os/cos"
 	"github.com/google/osv-scalibr/extractor/os/dpkg"
 	"github.com/google/osv-scalibr/extractor/os/rpm"
+	"github.com/google/osv-scalibr/extractor/os/testractor"
 	"github.com/google/osv-scalibr/extractor/osv"
 	"github.com/google/osv-scalibr/extractor/sbom/spdx"
 	"github.com/google/osv-scalibr/log"
 	"github.com/google/osv-scalibr/purl"
+	"github.com/google/osv-scanner/pkg/lockfile"
 )
 
 // LINT.IfChange
@@ -65,6 +66,7 @@ var (
 		&apk.Extractor{},
 		rpm.New(rpm.DefaultConfig()),
 		&cos.Extractor{},
+		&testractor.Extractor{},
 	}
 
 	// Collections of extractors.

extractor/os/testractor/extractor.go

@@ -0,0 +1,51 @@
+// Copyright 2024 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package cos extracts OS packages from Container Optimized OSes (go/cos).
+package testractor
+
+import (
+	"context"
+	"io/fs"
+
+	"github.com/google/osv-scalibr/extractor"
+	"github.com/google/osv-scalibr/purl"
+)
+
+// Extractor is a test extractor.
+type Extractor struct{}
+
+// Name of the extractor.
+func (e Extractor) Name() string { return "os/test" }
+
+// Version of the extractor.
+func (e Extractor) Version() int { return 0 }
+
+// FileRequired returns true if the specified file matches cos package info file pattern.
+func (e Extractor) FileRequired(path string, _ fs.FileMode) bool {
+	return false
+}
+
+// Extract extracts packages from cos package info files passed through the scan input.
+func (e Extractor) Extract(ctx context.Context, input *extractor.ScanInput) ([]*extractor.Inventory, error) {
+	return nil, nil
+}
+
+// ToPURL converts an inventory created by this extractor into a PURL.
+func (e Extractor) ToPURL(i *extractor.Inventory) (*purl.PackageURL, error) {
+	return &purl.PackageURL{}, nil
+}
+
+// ToCPEs is not applicable as this extractor does not infer CPEs from the Inventory.
+func (e Extractor) ToCPEs(i *extractor.Inventory) ([]string, error) { return []string{}, nil }