Return an error if document is not a dictionary

pkg/utils/yaml_utils/yaml_utils.go

@@ -1,6 +1,7 @@
 package yaml_utils
 
 import (
+	"errors"
 	"fmt"
 
 	"gopkg.in/yaml.v3"
@@ -24,6 +25,10 @@ func UpdateYamlValue(yamlBytes []byte, path []string, value string) ([]byte, err
 
 	body := node.Content[0]
 
+	if body.Kind != yaml.MappingNode {
+		return yamlBytes, errors.New("yaml document is not a dictionary")
+	}
+
 	updateYamlNode(body, path, value)
 
 	// Convert the updated YAML node back to YAML bytes.

pkg/utils/yaml_utils/yaml_utils_test.go

@@ -56,6 +56,16 @@ func TestUpdateYamlValue(t *testing.T) {
 			expectedOut: "foo:\n    bar: qux\n",
 			expectedErr: "",
 		},
+
+		// Error cases
+		{
+			name:        "existing document is not a dictionary",
+			in:          "42\n",
+			path:        []string{"foo"},
+			value:       "bar",
+			expectedOut: "42\n",
+			expectedErr: "yaml document is not a dictionary",
+		},
 	}
 
 	for _, test := range tests {