Decoder Properties (#1099)

* Decoder Properties

* Added properties round trip test

* Fixed property decode for github actions

* Refactored XML test to use common functions

* Switched formatScenario parameter order for more readablity

pkg/yqlib/decoder_test.go

@@ -0,0 +1,60 @@
+package yqlib
+
+import (
+	"bufio"
+	"bytes"
+	"strings"
+)
+
+type formatScenario struct {
+	input          string
+	indent         int
+	expression     string
+	expected       string
+	description    string
+	subdescription string
+	skipDoc        bool
+	scenarioType   string
+}
+
+func processFormatScenario(s formatScenario, decoder Decoder, encoder Encoder) string {
+
+	var output bytes.Buffer
+	writer := bufio.NewWriter(&output)
+
+	if decoder == nil {
+		decoder = NewYamlDecoder()
+	}
+
+	inputs, err := readDocuments(strings.NewReader(s.input), "sample.yml", 0, decoder)
+	if err != nil {
+		panic(err)
+	}
+
+	expression := s.expression
+	if expression == "" {
+		expression = "."
+	}
+
+	exp, err := getExpressionParser().ParseExpression(expression)
+
+	if err != nil {
+		panic(err)
+	}
+
+	context, err := NewDataTreeNavigator().GetMatchingNodes(Context{MatchingNodes: inputs}, exp)
+
+	if err != nil {
+		panic(err)
+	}
+
+	printer := NewPrinter(encoder, NewSinglePrinterWriter(writer))
+	err = printer.PrintResults(context.MatchingNodes)
+	if err != nil {
+		panic(err)
+	}
+	writer.Flush()
+
+	return output.String()
+
+}