Fixed trailing empty docs

cmd/commands_test.go

@@ -1264,6 +1264,30 @@ func TestWriteEmptyMultiDocCmd(t *testing.T) {
 	test.AssertResult(t, expectedOutput, result.Output)
 }
 
+func TestWriteTrailingEmptyMultiDocCmd(t *testing.T) {
+	content := `cat: frog
+---
+
+# empty
+`
+	filename := test.WriteTempYamlFile(content)
+	defer test.RemoveTempYamlFile(filename)
+
+	cmd := getRootCommand()
+	result := test.RunCmd(cmd, fmt.Sprintf("write %s c 7", filename))
+	if result.Error != nil {
+		t.Error(result.Error)
+	}
+	expectedOutput := `cat: frog
+c: 7
+---
+
+
+# empty
+`
+	test.AssertResult(t, expectedOutput, result.Output)
+}
+
 func TestWriteFromFileCmd(t *testing.T) {
 	content := `b:
   c: 3

cmd/utils.go

@@ -226,7 +226,7 @@ func mapYamlDecoder(updateData updateDataFn, encoder yqlib.Encoder) yamlDecoderF
 				dataBucket = yaml.Node{Kind: yaml.DocumentNode, Content: make([]*yaml.Node, 1)}
 				child := yaml.Node{Kind: yaml.MappingNode}
 				dataBucket.Content[0] = &child
-			} else if isNullDocument(&dataBucket) {
+			} else if isNullDocument(&dataBucket) && (updateAll || docIndexInt == currentIndex) {
 				child := yaml.Node{Kind: yaml.MappingNode}
 				dataBucket.Content[0] = &child
 			} else if errorReading == io.EOF {