Added key operator

pkg/yqlib/candidate_node.go

@@ -11,6 +11,7 @@ import (
 type CandidateNode struct {
 	Node   *yaml.Node     // the actual node
 	Parent *CandidateNode // parent node
+	Key    *yaml.Node     // node key, if this is a value from a map (or index in an array)
 
 	LeadingContent string
 
@@ -38,11 +39,41 @@ func (n *CandidateNode) AsList() *list.List {
 	return elMap
 }
 
-func (n *CandidateNode) CreateChild(path interface{}, node *yaml.Node) *CandidateNode {
+func (n *CandidateNode) CreateChildInMap(key *yaml.Node, node *yaml.Node) *CandidateNode {
+	var value interface{} = nil
+	if key != nil {
+		value = key.Value
+	}
 	return &CandidateNode{
 		Node:      node,
-		Path:      n.createChildPath(path),
+		Path:      n.createChildPath(value),
 		Parent:    n,
+		Key:       key,
+		Document:  n.Document,
+		Filename:  n.Filename,
+		FileIndex: n.FileIndex,
+	}
+}
+
+func (n *CandidateNode) CreateChildInArray(index int, node *yaml.Node) *CandidateNode {
+	return &CandidateNode{
+		Node:      node,
+		Path:      n.createChildPath(index),
+		Parent:    n,
+		Key:       &yaml.Node{Kind: yaml.ScalarNode, Value: fmt.Sprintf("%v", index), Tag: "!!int"},
+		Document:  n.Document,
+		Filename:  n.Filename,
+		FileIndex: n.FileIndex,
+	}
+}
+
+func (n *CandidateNode) CreateReplacement(node *yaml.Node) *CandidateNode {
+	return &CandidateNode{
+		Node:      node,
+		Path:      n.createChildPath(nil),
+		Parent:    n.Parent,
+		Key:       n.Key,
+		IsMapKey:  n.IsMapKey,
 		Document:  n.Document,
 		Filename:  n.Filename,
 		FileIndex: n.FileIndex,

pkg/yqlib/doc/keys.md

@@ -34,3 +34,38 @@ will output
 - 1
 ```
 
+## Update map key
+Given a sample.yml file of:
+```yaml
+a:
+  x: 3
+  y: 4
+```
+then
+```bash
+yq eval '(.a.x | key) = "meow"' sample.yml
+```
+will output
+```yaml
+a:
+  meow: 3
+  y: 4
+```
+
+## Get comment from map key
+Given a sample.yml file of:
+```yaml
+a:
+  # comment on key
+  x: 3
+  y: 4
+```
+then
+```bash
+yq eval '.a.x | key | headComment' sample.yml
+```
+will output
+```yaml
+comment on key
+```
+

pkg/yqlib/expression_tokeniser.go

@@ -368,6 +368,8 @@ func initLexer() (*lex.Lexer, error) {
 	lexer.Add([]byte(`contains`), opToken(containsOpType))
 
 	lexer.Add([]byte(`split`), opToken(splitStringOpType))
+
+	lexer.Add([]byte(`key`), opToken(getKeyOpType))
 	lexer.Add([]byte(`keys`), opToken(keysOpType))
 
 	lexer.Add([]byte(`style`), opAssignableToken(getStyleOpType, assignStyleOpType))

pkg/yqlib/lib.go

@@ -78,6 +78,9 @@ var splitDocumentOpType = &operationType{Type: "SPLIT_DOC", NumArgs: 0, Preceden
 var getVariableOpType = &operationType{Type: "GET_VARIABLE", NumArgs: 0, Precedence: 55, Handler: getVariableOperator}
 var getStyleOpType = &operationType{Type: "GET_STYLE", NumArgs: 0, Precedence: 50, Handler: getStyleOperator}
 var getTagOpType = &operationType{Type: "GET_TAG", NumArgs: 0, Precedence: 50, Handler: getTagOperator}
+
+var getKeyOpType = &operationType{Type: "GET_KEY", NumArgs: 0, Precedence: 50, Handler: getKeyOperator}
+
 var getCommentOpType = &operationType{Type: "GET_COMMENT", NumArgs: 0, Precedence: 50, Handler: getCommentsOperator}
 var getAnchorOpType = &operationType{Type: "GET_ANCHOR", NumArgs: 0, Precedence: 50, Handler: getAnchorOperator}
 var getAliasOptype = &operationType{Type: "GET_ALIAS", NumArgs: 0, Precedence: 50, Handler: getAliasOperator}

pkg/yqlib/operator_add.go

@@ -45,10 +45,10 @@ func add(d *dataTreeNavigator, context Context, lhs *CandidateNode, rhs *Candida
 	lhsNode := lhs.Node
 
 	if lhsNode.Tag == "!!null" {
-		return lhs.CreateChild(nil, rhs.Node), nil
+		return lhs.CreateReplacement(rhs.Node), nil
 	}
 
-	target := lhs.CreateChild(nil, &yaml.Node{})
+	target := lhs.CreateReplacement(&yaml.Node{})
 
 	switch lhsNode.Kind {
 	case yaml.MappingNode:
@@ -60,7 +60,7 @@ func add(d *dataTreeNavigator, context Context, lhs *CandidateNode, rhs *Candida
 		target.Node.Content = append(lhsNode.Content, toNodes(rhs)...)
 	case yaml.ScalarNode:
 		if rhs.Node.Kind != yaml.ScalarNode {
-			return nil, fmt.Errorf("%v (%v) cannot be added to a %v", rhs.Node.Tag, rhs.Path, lhsNode.Tag)
+			return nil, fmt.Errorf("%v (%v) cannot be added to a 2%v", rhs.Node.Tag, rhs.Path, lhsNode.Tag)
 		}
 		target.Node.Kind = yaml.ScalarNode
 		target.Node.Style = lhsNode.Style

pkg/yqlib/operator_anchors_aliases.go

@@ -56,7 +56,7 @@ func getAliasOperator(d *dataTreeNavigator, context Context, expressionNode *Exp
 	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		node := &yaml.Node{Kind: yaml.ScalarNode, Value: candidate.Node.Value, Tag: "!!str"}
-		result := candidate.CreateChild(nil, node)
+		result := candidate.CreateReplacement(node)
 		results.PushBack(result)
 	}
 	return context.ChildContext(results), nil
@@ -112,7 +112,7 @@ func getAnchorOperator(d *dataTreeNavigator, context Context, expressionNode *Ex
 		candidate := el.Value.(*CandidateNode)
 		anchor := candidate.Node.Anchor
 		node := &yaml.Node{Kind: yaml.ScalarNode, Value: anchor, Tag: "!!str"}
-		result := candidate.CreateChild(nil, node)
+		result := candidate.CreateReplacement(node)
 		results.PushBack(result)
 	}
 	return context.ChildContext(results), nil

pkg/yqlib/operator_collect.go

@@ -20,7 +20,7 @@ func collectOperator(d *dataTreeNavigator, context Context, expressionNode *Expr
 	node := &yaml.Node{Kind: yaml.SequenceNode, Tag: "!!seq"}
 	var collectC *CandidateNode
 	if context.MatchingNodes.Front() != nil {
-		collectC = context.MatchingNodes.Front().Value.(*CandidateNode).CreateChild(nil, node)
+		collectC = context.MatchingNodes.Front().Value.(*CandidateNode).CreateReplacement(node)
 		if len(collectC.Path) > 0 {
 			collectC.Path = collectC.Path[:len(collectC.Path)-1]
 		}

pkg/yqlib/operator_collect_object.go

@@ -37,7 +37,7 @@ func collectObjectOperator(d *dataTreeNavigator, originalContext Context, expres
 	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
 		candidateNode := el.Value.(*CandidateNode)
 		for i := 0; i < len(first.Node.Content); i++ {
-			rotated[i].PushBack(candidateNode.CreateChild(i, candidateNode.Node.Content[i]))
+			rotated[i].PushBack(candidateNode.CreateChildInArray(i, candidateNode.Node.Content[i]))
 		}
 	}
 

pkg/yqlib/operator_comments.go

@@ -105,7 +105,7 @@ func getCommentsOperator(d *dataTreeNavigator, context Context, expressionNode *
 		comment = subsequentCommentCharaterRegExp.ReplaceAllString(comment, "\n")
 
 		node := &yaml.Node{Kind: yaml.ScalarNode, Value: comment, Tag: "!!str"}
-		result := candidate.CreateChild(nil, node)
+		result := candidate.CreateReplacement(node)
 		results.PushBack(result)
 	}
 	return context.ChildContext(results), nil

pkg/yqlib/operator_delete.go

@@ -47,7 +47,7 @@ func deleteFromMap(candidate *CandidateNode, childPath interface{}) {
 		key := contents[index]
 		value := contents[index+1]
 
-		childCandidate := candidate.CreateChild(key.Value, value)
+		childCandidate := candidate.CreateChildInMap(key, value)
 
 		shouldDelete := key.Value == childPath
 

pkg/yqlib/operator_document_index.go

@@ -13,7 +13,7 @@ func getDocumentIndexOperator(d *dataTreeNavigator, context Context, expressionN
 	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		node := &yaml.Node{Kind: yaml.ScalarNode, Value: fmt.Sprintf("%v", candidate.Document), Tag: "!!int"}
-		scalar := candidate.CreateChild(nil, node)
+		scalar := candidate.CreateReplacement(node)
 		results.PushBack(scalar)
 	}
 	return context.ChildContext(results), nil

pkg/yqlib/operator_encoder_decoder.go

@@ -61,7 +61,7 @@ func encodeOperator(d *dataTreeNavigator, context Context, expressionNode *Expre
 		}
 
 		stringContentNode := &yaml.Node{Kind: yaml.ScalarNode, Tag: "!!str", Value: stringValue}
-		results.PushBack(candidate.CreateChild(nil, stringContentNode))
+		results.PushBack(candidate.CreateReplacement(stringContentNode))
 	}
 	return context.ChildContext(results), nil
 }
@@ -85,7 +85,7 @@ func decodeOperator(d *dataTreeNavigator, context Context, expressionNode *Expre
 		//first node is a doc
 		node := unwrapDoc(&dataBucket)
 
-		results.PushBack(candidate.CreateChild(nil, node))
+		results.PushBack(candidate.CreateReplacement(node))
 	}
 	return context.ChildContext(results), nil
 }

pkg/yqlib/operator_entries.go

@@ -20,7 +20,7 @@ func entrySeqFor(key *yaml.Node, value *yaml.Node) *yaml.Node {
 
 func toEntriesFromMap(candidateNode *CandidateNode) *CandidateNode {
 	var sequence = &yaml.Node{Kind: yaml.SequenceNode, Tag: "!!seq"}
-	var entriesNode = candidateNode.CreateChild(nil, sequence)
+	var entriesNode = candidateNode.CreateReplacement(sequence)
 
 	var contents = unwrapDoc(candidateNode.Node).Content
 	for index := 0; index < len(contents); index = index + 2 {
@@ -34,7 +34,7 @@ func toEntriesFromMap(candidateNode *CandidateNode) *CandidateNode {
 
 func toEntriesfromSeq(candidateNode *CandidateNode) *CandidateNode {
 	var sequence = &yaml.Node{Kind: yaml.SequenceNode, Tag: "!!seq"}
-	var entriesNode = candidateNode.CreateChild(nil, sequence)
+	var entriesNode = candidateNode.CreateReplacement(sequence)
 
 	var contents = unwrapDoc(candidateNode.Node).Content
 	for index := 0; index < len(contents); index = index + 1 {
@@ -94,7 +94,7 @@ func parseEntry(d *dataTreeNavigator, entry *yaml.Node, position int) (*yaml.Nod
 
 func fromEntries(d *dataTreeNavigator, candidateNode *CandidateNode) (*CandidateNode, error) {
 	var node = &yaml.Node{Kind: yaml.MappingNode, Tag: "!!map"}
-	var mapCandidateNode = candidateNode.CreateChild(nil, node)
+	var mapCandidateNode = candidateNode.CreateReplacement(node)
 
 	var contents = unwrapDoc(candidateNode.Node).Content
 

pkg/yqlib/operator_file.go

@@ -15,7 +15,7 @@ func getFilenameOperator(d *dataTreeNavigator, context Context, expressionNode *
 	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		node := &yaml.Node{Kind: yaml.ScalarNode, Value: candidate.Filename, Tag: "!!str"}
-		result := candidate.CreateChild(nil, node)
+		result := candidate.CreateReplacement(node)
 		results.PushBack(result)
 	}
 
@@ -30,7 +30,7 @@ func getFileIndexOperator(d *dataTreeNavigator, context Context, expressionNode
 	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		node := &yaml.Node{Kind: yaml.ScalarNode, Value: fmt.Sprintf("%v", candidate.FileIndex), Tag: "!!int"}
-		result := candidate.CreateChild(nil, node)
+		result := candidate.CreateReplacement(node)
 		results.PushBack(result)
 	}
 

pkg/yqlib/operator_group_by.go

@@ -67,7 +67,7 @@ func groupBy(d *dataTreeNavigator, context Context, expressionNode *ExpressionNo
 			resultNode.Content = append(resultNode.Content, groupResultNode)
 		}
 
-		results.PushBack(candidate.CreateChild(nil, resultNode))
+		results.PushBack(candidate.CreateReplacement(resultNode))
 
 	}
 

pkg/yqlib/operator_keys.go

@@ -7,6 +7,21 @@ import (
 	"gopkg.in/yaml.v3"
 )
 
+func getKeyOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+	log.Debugf("-- getKeyOperator")
+
+	var results = list.New()
+
+	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+		candidate := el.Value.(*CandidateNode)
+
+		results.PushBack(candidate.CreateReplacement(candidate.Key))
+	}
+
+	return context.ChildContext(results), nil
+
+}
+
 func keysOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
 	log.Debugf("-- keysOperator")
 
@@ -24,7 +39,7 @@ func keysOperator(d *dataTreeNavigator, context Context, expressionNode *Express
 			return Context{}, fmt.Errorf("Cannot get keys of %v, keys only works for maps and arrays", node.Tag)
 		}
 
-		result := candidate.CreateChild(nil, targetNode)
+		result := candidate.CreateReplacement(targetNode)
 		results.PushBack(result)
 	}
 

pkg/yqlib/operator_keys_test.go

@@ -37,6 +37,22 @@ var keysOperatorScenarios = []expressionScenario{
 			"D0, P[], (!!seq)::[]\n",
 		},
 	},
+	{
+		description: "Update map key",
+		document:    "a:\n  x: 3\n  y: 4",
+		expression:  `(.a.x | key) = "meow"`,
+		expected: []string{
+			"D0, P[], (doc)::a:\n    meow: 3\n    y: 4\n",
+		},
+	},
+	{
+		description: "Get comment from map key",
+		document:    "a: \n  # comment on key\n  x: 3\n  y: 4",
+		expression:  `.a.x | key | headComment`,
+		expected: []string{
+			"D0, P[a x], (!!str)::comment on key\n",
+		},
+	},
 }
 
 func TestKeysOperatorScenarios(t *testing.T) {

pkg/yqlib/operator_length.go

@@ -31,7 +31,7 @@ func lengthOperator(d *dataTreeNavigator, context Context, expressionNode *Expre
 		}
 
 		node := &yaml.Node{Kind: yaml.ScalarNode, Value: fmt.Sprintf("%v", length), Tag: "!!int"}
-		result := candidate.CreateChild(nil, node)
+		result := candidate.CreateReplacement(node)
 		results.PushBack(result)
 	}
 

pkg/yqlib/operator_multiply.go

@@ -67,7 +67,7 @@ func multiply(preferences multiplyPreferences) func(d *dataTreeNavigator, contex
 }
 
 func multiplyFloats(lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
-	target := lhs.CreateChild(nil, &yaml.Node{})
+	target := lhs.CreateReplacement(&yaml.Node{})
 	target.Node.Kind = yaml.ScalarNode
 	target.Node.Style = lhs.Node.Style
 	target.Node.Tag = "!!float"
@@ -85,7 +85,7 @@ func multiplyFloats(lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, err
 }
 
 func multiplyIntegers(lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
-	target := lhs.CreateChild(nil, &yaml.Node{})
+	target := lhs.CreateReplacement(&yaml.Node{})
 	target.Node.Kind = yaml.ScalarNode
 	target.Node.Style = lhs.Node.Style
 	target.Node.Tag = "!!int"

pkg/yqlib/operator_path.go

@@ -31,7 +31,7 @@ func getPathOperator(d *dataTreeNavigator, context Context, expressionNode *Expr
 			content[pathIndex] = createPathNodeFor(path)
 		}
 		node.Content = content
-		result := candidate.CreateChild(nil, node)
+		result := candidate.CreateReplacement(node)
 		results.PushBack(result)
 	}
 

pkg/yqlib/operator_strings.go

@@ -66,7 +66,7 @@ func substituteStringOperator(d *dataTreeNavigator, context Context, expressionN
 		}
 
 		targetNode := substitute(node.Value, regEx, replacementText)
-		result := candidate.CreateChild(nil, targetNode)
+		result := candidate.CreateReplacement(targetNode)
 		results.PushBack(result)
 	}
 
@@ -150,7 +150,7 @@ func match(matchPrefs matchPreferences, regEx *regexp.Regexp, candidate *Candida
 			createScalarNode("captures", "captures"),
 			capturesNode,
 		)
-		results.PushBack(candidate.CreateChild(nil, node))
+		results.PushBack(candidate.CreateReplacement(node))
 
 	}
 
@@ -187,7 +187,7 @@ func capture(matchPrefs matchPreferences, regEx *regexp.Regexp, candidate *Candi
 			}
 		}
 
-		results.PushBack(candidate.CreateChild(nil, capturesNode))
+		results.PushBack(candidate.CreateReplacement(capturesNode))
 
 	}
 
@@ -321,7 +321,7 @@ func joinStringOperator(d *dataTreeNavigator, context Context, expressionNode *E
 			return Context{}, fmt.Errorf("cannot join with %v, can only join arrays of scalars", node.Tag)
 		}
 		targetNode := join(node.Content, joinStr)
-		result := candidate.CreateChild(nil, targetNode)
+		result := candidate.CreateReplacement(targetNode)
 		results.PushBack(result)
 	}
 
@@ -365,7 +365,7 @@ func splitStringOperator(d *dataTreeNavigator, context Context, expressionNode *
 			return Context{}, fmt.Errorf("Cannot split %v, can only split strings", node.Tag)
 		}
 		targetNode := split(node.Value, splitStr)
-		result := candidate.CreateChild(nil, targetNode)
+		result := candidate.CreateReplacement(targetNode)
 		results.PushBack(result)
 	}
 

pkg/yqlib/operator_style.go

@@ -100,7 +100,7 @@ func getStyleOperator(d *dataTreeNavigator, context Context, expressionNode *Exp
 			style = "<unknown>"
 		}
 		node := &yaml.Node{Kind: yaml.ScalarNode, Value: style, Tag: "!!str"}
-		result := candidate.CreateChild(nil, node)
+		result := candidate.CreateReplacement(node)
 		results.PushBack(result)
 	}
 

pkg/yqlib/operator_subtract.go

@@ -49,10 +49,10 @@ func subtract(d *dataTreeNavigator, context Context, lhs *CandidateNode, rhs *Ca
 	lhsNode := lhs.Node
 
 	if lhsNode.Tag == "!!null" {
-		return lhs.CreateChild(nil, rhs.Node), nil
+		return lhs.CreateReplacement(rhs.Node), nil
 	}
 
-	target := lhs.CreateChild(nil, &yaml.Node{})
+	target := lhs.CreateReplacement(&yaml.Node{})
 
 	switch lhsNode.Kind {
 	case yaml.MappingNode:

pkg/yqlib/operator_tag.go

@@ -55,7 +55,7 @@ func getTagOperator(d *dataTreeNavigator, context Context, expressionNode *Expre
 	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		node := &yaml.Node{Kind: yaml.ScalarNode, Value: unwrapDoc(candidate.Node).Tag, Tag: "!!str"}
-		result := candidate.CreateChild(nil, node)
+		result := candidate.CreateReplacement(node)
 		results.PushBack(result)
 	}
 

pkg/yqlib/operator_traverse_path.go

@@ -70,7 +70,7 @@ func traverse(d *dataTreeNavigator, context Context, matchingNode *CandidateNode
 	case yaml.DocumentNode:
 		log.Debug("digging into doc node")
 
-		return traverse(d, context, matchingNode.CreateChild(nil, matchingNode.Node.Content[0]), operation)
+		return traverse(d, context, matchingNode.CreateChildInMap(nil, matchingNode.Node.Content[0]), operation)
 	default:
 		return list.New(), nil
 	}
@@ -147,7 +147,7 @@ func traverseArrayIndices(context Context, matchingNode *CandidateNode, indicesT
 	} else if node.Kind == yaml.MappingNode {
 		return traverseMapWithIndices(context, matchingNode, indicesToTraverse, prefs)
 	} else if node.Kind == yaml.DocumentNode {
-		return traverseArrayIndices(context, matchingNode.CreateChild(nil, matchingNode.Node.Content[0]), indicesToTraverse, prefs)
+		return traverseArrayIndices(context, matchingNode.CreateChildInMap(nil, matchingNode.Node.Content[0]), indicesToTraverse, prefs)
 	}
 	log.Debugf("OperatorArrayTraverse skipping %v as its a %v", matchingNode, node.Tag)
 	return list.New(), nil
@@ -178,10 +178,9 @@ func traverseArrayWithIndices(candidate *CandidateNode, indices []*yaml.Node, pr
 	node := unwrapDoc(candidate.Node)
 	if len(indices) == 0 {
 		log.Debug("splatting")
-		var index int64
+		var index int
-		for index = 0; index < int64(len(node.Content)); index = index + 1 {
+		for index = 0; index < len(node.Content); index = index + 1 {
-
+			newMatches.PushBack(candidate.CreateChildInArray(index, node.Content[index]))
-			newMatches.PushBack(candidate.CreateChild(index, node.Content[index]))
 		}
 		return newMatches, nil
 
@@ -211,7 +210,7 @@ func traverseArrayWithIndices(candidate *CandidateNode, indices []*yaml.Node, pr
 			return nil, fmt.Errorf("Index [%v] out of range, array size is %v", index, contentLength)
 		}
 
-		newMatches.PushBack(candidate.CreateChild(index, node.Content[indexToUse]))
+		newMatches.PushBack(candidate.CreateChildInArray(int(index), node.Content[indexToUse]))
 	}
 	return newMatches, nil
 }
@@ -237,13 +236,13 @@ func traverseMap(context Context, matchingNode *CandidateNode, key string, prefs
 
 		if prefs.IncludeMapKeys {
 			log.Debug("including key")
-			candidateNode := matchingNode.CreateChild(key, keyNode)
+			candidateNode := matchingNode.CreateChildInMap(keyNode, keyNode)
 			candidateNode.IsMapKey = true
 			newMatches.Set(fmt.Sprintf("keyOf-%v", candidateNode.GetKey()), candidateNode)
 		}
 		if !prefs.DontIncludeMapValues {
 			log.Debug("including value")
-			candidateNode := matchingNode.CreateChild(key, valueNode)
+			candidateNode := matchingNode.CreateChildInMap(keyNode, valueNode)
 			newMatches.Set(candidateNode.GetKey(), candidateNode)
 		}
 	}
@@ -282,13 +281,13 @@ func doTraverseMap(newMatches *orderedmap.OrderedMap, candidate *CandidateNode,
 			log.Debug("MATCHED")
 			if prefs.IncludeMapKeys {
 				log.Debug("including key")
-				candidateNode := candidate.CreateChild(key.Value, key)
+				candidateNode := candidate.CreateChildInMap(key, key)
 				candidateNode.IsMapKey = true
 				newMatches.Set(fmt.Sprintf("keyOf-%v", candidateNode.GetKey()), candidateNode)
 			}
 			if !prefs.DontIncludeMapValues {
 				log.Debug("including value")
-				candidateNode := candidate.CreateChild(key.Value, value)
+				candidateNode := candidate.CreateChildInMap(key, value)
 				newMatches.Set(candidateNode.GetKey(), candidateNode)
 			}
 		}
@@ -300,7 +299,7 @@ func doTraverseMap(newMatches *orderedmap.OrderedMap, candidate *CandidateNode,
 func traverseMergeAnchor(newMatches *orderedmap.OrderedMap, originalCandidate *CandidateNode, value *yaml.Node, wantedKey string, prefs traversePreferences, splat bool) error {
 	switch value.Kind {
 	case yaml.AliasNode:
-		candidateNode := originalCandidate.CreateChild(nil, value.Alias)
+		candidateNode := originalCandidate.CreateReplacement(value.Alias)
 		return doTraverseMap(newMatches, candidateNode, wantedKey, prefs, splat)
 	case yaml.SequenceNode:
 		for _, childValue := range value.Content {

pkg/yqlib/operator_unique.go

@@ -56,7 +56,7 @@ func uniqueBy(d *dataTreeNavigator, context Context, expressionNode *ExpressionN
 			resultNode.Content = append(resultNode.Content, el.Value.(*yaml.Node))
 		}
 
-		results.PushBack(candidate.CreateChild(nil, resultNode))
+		results.PushBack(candidate.CreateReplacement(resultNode))
 	}
 
 	return context.ChildContext(results), nil

pkg/yqlib/operators.go

@@ -144,7 +144,7 @@ func createBooleanCandidate(owner *CandidateNode, value bool) *CandidateNode {
 		valString = "false"
 	}
 	node := &yaml.Node{Kind: yaml.ScalarNode, Value: valString, Tag: "!!bool"}
-	return owner.CreateChild(nil, node)
+	return owner.CreateReplacement(node)
 }
 
 func createTraversalTree(path []interface{}, traversePrefs traversePreferences, targetKey bool) *ExpressionNode {