feat(python): support egg format (fanal#266)

Author: knqyf263

analyzer/language/python/packaging/packaging.go

@@ -21,7 +21,12 @@ const version = 1
 
 var (
 	requiredFiles = []string{
-		// egg
+		// .egg format
+		// https://setuptools.readthedocs.io/en/latest/deprecated/python_eggs.html#eggs-and-their-formats
+		"EGG-INFO/PKG-INFO",
+
+		// .egg-info format: .egg-info can be a file or directory
+		// https://setuptools.readthedocs.io/en/latest/deprecated/python_eggs.html#eggs-and-their-formats
 		".egg-info",
 		".egg-info/PKG-INFO",
 

analyzer/language/python/packaging/packaging_test.go

@@ -113,6 +113,11 @@ func Test_packagingAnalyzer_Required(t *testing.T) {
 		filePath string
 		want     bool
 	}{
+		{
+			name:     "egg",
+			filePath: "python2.7/site-packages/cssutils-1.0-py2.7.egg/EGG-INFO/PKG-INFO",
+			want:     true,
+		},
 		{
 			name:     "egg-info",
 			filePath: "python3.8/site-packages/wrapt-1.12.1.egg-info",