Split dpk source into name and version (#297)

* Split dpk source into name and version

Signed-off-by: Zach Hill <zach@anchore.com>

* update dpkg status source name parsing

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

Co-authored-by: Dan Luhring <luhring@users.noreply.github.com>
Co-authored-by: Alex Goodman <alex.goodman@anchore.com>

syft/cataloger/deb/parse_dpkg_status.go

@@ -5,9 +5,12 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"regexp"
 	"strconv"
 	"strings"
 
+	"github.com/anchore/syft/internal"
+
 	"github.com/anchore/syft/syft/pkg"
 	"github.com/mitchellh/mapstructure"
 )
@@ -45,6 +48,7 @@ func parseDpkgStatus(reader io.Reader) ([]pkg.Package, error) {
 }
 
 // parseDpkgStatusEntry returns an individual Dpkg entry, or returns errEndOfPackages if there are no more packages to parse from the reader.
+// nolint:funlen
 func parseDpkgStatusEntry(reader *bufio.Reader) (entry pkg.DpkgMetadata, err error) {
 	dpkgFields := make(map[string]interface{})
 	var retErr error
@@ -105,9 +109,29 @@ func parseDpkgStatusEntry(reader *bufio.Reader) (entry pkg.DpkgMetadata, err err
 		return pkg.DpkgMetadata{}, err
 	}
 
+	name, version := extractSourceVersion(entry.Source)
+	if version != "" {
+		entry.SourceVersion = version
+		entry.Source = name
+	}
+
 	return entry, retErr
 }
 
+// match examples:
+// "a-thing (1.2.3)"     name="a-thing" version="1.2.3"
+// "a-thing"             name="a-thing" version=""
+// ""                    name=""        version=""
+var sourceRegexp = regexp.MustCompile(`(?P<name>\S+)( \((?P<version>.*)\))?`)
+
+// If the source entry string is of the form "<name> (<version>)" then parse and return the components, if
+// of the "<name>" form, then return name and nil
+func extractSourceVersion(source string) (string, string) {
+	// special handling for the Source field since it has formatted data
+	match := internal.MatchCaptureGroups(sourceRegexp, source)
+	return match["name"], match["version"]
+}
+
 // handleNewKeyValue parse a new key-value pair from the given unprocessed line
 func handleNewKeyValue(line string) (string, interface{}, error) {
 	if i := strings.Index(line, ":"); i > 0 {