migrate syft/cataloger to syft/pkg/cataloger

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

syft/pkg/cataloger/python/parse_setup.go

@@ -0,0 +1,50 @@
+package python
+
+import (
+	"bufio"
+	"io"
+	"regexp"
+	"strings"
+
+	"github.com/anchore/syft/syft/pkg"
+	"github.com/anchore/syft/syft/pkg/cataloger/common"
+)
+
+// integrity check
+var _ common.ParserFn = parseSetup
+
+// match examples:
+//		'pathlib3==2.2.0;python_version<"3.6"'  --> match(name=pathlib3 version=2.2.0)
+//		 "mypy==v0.770",                        --> match(name=mypy version=v0.770)
+//		" mypy2 == v0.770", ' mypy3== v0.770',  --> match(name=mypy2 version=v0.770), match(name=mypy3, version=v0.770)
+var pinnedDependency = regexp.MustCompile(`['"]\W?(\w+\W?==\W?[\w\.]*)`)
+
+func parseSetup(_ string, reader io.Reader) ([]pkg.Package, error) {
+	packages := make([]pkg.Package, 0)
+
+	scanner := bufio.NewScanner(reader)
+
+	for scanner.Scan() {
+		line := scanner.Text()
+		line = strings.TrimRight(line, "\n")
+
+		for _, match := range pinnedDependency.FindAllString(line, -1) {
+			parts := strings.Split(match, "==")
+			if len(parts) != 2 {
+				continue
+			}
+			name := strings.Trim(parts[0], "'\"")
+			name = strings.TrimSpace(name)
+
+			version := strings.TrimSpace(parts[len(parts)-1])
+			packages = append(packages, pkg.Package{
+				Name:     strings.Trim(name, "'\""),
+				Version:  strings.Trim(version, "'\""),
+				Language: pkg.Python,
+				Type:     pkg.PythonPkg,
+			})
+		}
+	}
+
+	return packages, nil
+}