Incrementing version

.github/FUNDING.yml

@@ -1 +0,0 @@
-github: mikefarah

.github/workflows/release.yml

@@ -40,7 +40,17 @@ jobs:
       IMAGE_NAME: mikefarah/yq
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - name: Get latest release tag      
+        uses: oprypin/find-latest-tag@v1
+        with:
+          repository: mikefarah/yq  # The repository to scan.
+          releases-only: true  # We know that all relevant tags have a GitHub release for them.
+        id: yq  
+        
+      - name: Clone source code
+        uses: actions/checkout@v2
+        with:
+          ref: ${{ steps.yq.outputs.tag }}
       
       - name: Set up QEMU
         uses: docker/setup-qemu-action@v1

README.md

@@ -90,7 +90,7 @@ docker run --rm -v "${PWD}":/workdir mikefarah/yq <command> [flags] [expression
 #### Run commands interactively:
 
 ```bash
-docker run --rm -it -v "${PWD}":/workdir --entrypoint sh mikefarah/yq
+docker run --rm -it -v "${PWD}":/workdir mikefarah/yq sh
 ```
 
 It can be useful to have a bash function to avoid typing the whole docker command:
@@ -103,7 +103,7 @@ yq() {
 
 ### Go Get:
 ```
-GO111MODULE=on go get github.com/mikefarah/yq/v4
+GO111MODULE=on go get github.com/mikefarah/yq
 ```
 
 ## Community Supported Installation methods

cmd/evaluate_all_command.go

@@ -42,21 +42,14 @@ func evaluateAll(cmd *cobra.Command, args []string) error {
 		colorsEnabled = true
 	}
 
-	firstFileIndex := -1
+	if writeInplace && len(args) < 2 {
-	if !nullInput && len(args) == 1 {
-		firstFileIndex = 0
-	} else if len(args) > 1 {
-		firstFileIndex = 1
-	}
-
-	if writeInplace && (firstFileIndex == -1) {
 		return fmt.Errorf("Write inplace flag only applicable when giving an expression and at least one file")
 	}
 
 	if writeInplace {
 		// only use colors if its forced
 		colorsEnabled = forceColor
-		writeInPlaceHandler := yqlib.NewWriteInPlaceHandler(args[firstFileIndex])
+		writeInPlaceHandler := yqlib.NewWriteInPlaceHandler(args[1])
 		out, err = writeInPlaceHandler.CreateTempFile()
 		if err != nil {
 			return err

cmd/evalute_sequence_command.go

@@ -62,21 +62,14 @@ func evaluateSequence(cmd *cobra.Command, args []string) error {
 		colorsEnabled = true
 	}
 
-	firstFileIndex := -1
+	if writeInplace && len(args) < 2 {
-	if !nullInput && len(args) == 1 {
-		firstFileIndex = 0
-	} else if len(args) > 1 {
-		firstFileIndex = 1
-	}
-
-	if writeInplace && (firstFileIndex == -1) {
 		return fmt.Errorf("Write inplace flag only applicable when giving an expression and at least one file")
 	}
 
 	if writeInplace {
 		// only use colors if its forced
 		colorsEnabled = forceColor
-		writeInPlaceHandler := yqlib.NewWriteInPlaceHandler(args[firstFileIndex])
+		writeInPlaceHandler := yqlib.NewWriteInPlaceHandler(args[1])
 		out, err = writeInPlaceHandler.CreateTempFile()
 		if err != nil {
 			return err
@@ -109,7 +102,7 @@ func evaluateSequence(cmd *cobra.Command, args []string) error {
 			err = streamEvaluator.EvaluateFiles(processExpression(""), []string{args[0]}, printer)
 		}
 	default:
-		err = streamEvaluator.EvaluateFiles(processExpression(args[0]), args[1:], printer)
+		err = streamEvaluator.EvaluateFiles(args[0], args[1:], printer)
 	}
 	completedSuccessfully = err == nil
 

cmd/version.go

@@ -11,7 +11,7 @@ var (
 	GitDescribe string
 
 	// Version is main version number that is being run at the moment.
-	Version = "4.5.1"
+	Version = "4.4.0"
 
 	// VersionPrerelease is a pre-release marker for the version. If this is "" (empty string)
 	// then it means that it is a final release. Otherwise, this is a pre-release

examples/data1.yaml

@@ -1,6 +1,4 @@
-a:
+a: simple # just the best
-  key1: "value1"
+b: [1, 2]
-  key2: 2.6
+c:
-  ab:
+  test: 1
-    key1: 6
-    key2: "h"

github-action/Dockerfile

@@ -1,4 +1,4 @@
-FROM mikefarah/yq:4.5.1
+FROM mikefarah/yq:4.4.0
 
 COPY entrypoint.sh /entrypoint.sh
 

go.mod

@@ -1,14 +1,14 @@
 module github.com/mikefarah/yq/v4
 
 require (
-	github.com/elliotchance/orderedmap v1.4.0
+	github.com/elliotchance/orderedmap v1.3.0
 	github.com/fatih/color v1.10.0
-	github.com/goccy/go-yaml v1.8.8
+	github.com/goccy/go-yaml v1.8.4
-	github.com/jinzhu/copier v0.2.3
+	github.com/jinzhu/copier v0.1.0
 	github.com/spf13/cobra v1.1.1
 	github.com/timtadh/data-structures v0.5.3 // indirect
 	github.com/timtadh/lexmachine v0.2.2
-	golang.org/x/sys v0.0.0-20210124154548-22da62e12c0c // indirect
+	golang.org/x/sys v0.0.0-20210105210732-16f7687f5001 // indirect
 	gopkg.in/op/go-logging.v1 v1.0.0-20160211212156-b2cb9fa56473
 	gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b
 )

go.sum

@@ -36,8 +36,8 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/dgrijalva/jwt-go v3.2.0+incompatible/go.mod h1:E3ru+11k8xSBh+hMPgOLZmtrrCbhqsmaPHjLKYnJCaQ=
 github.com/dgryski/go-sip13 v0.0.0-20181026042036-e10d5fee7954/go.mod h1:vAd38F8PWV+bWy6jNmig1y/TA+kYO4g3RSRF0IAv0no=
-github.com/elliotchance/orderedmap v1.4.0 h1:wZtfeEONCbx6in1CZyE6bELEt/vFayMvsxqI5SgsR+A=
+github.com/elliotchance/orderedmap v1.3.0 h1:k6m77/d0zCXTjsk12nX40TkEBkSICq8T4s6R6bpCqU0=
-github.com/elliotchance/orderedmap v1.4.0/go.mod h1:wsDwEaX5jEoyhbs7x93zk2H/qv0zwuhg4inXhDkYqys=
+github.com/elliotchance/orderedmap v1.3.0/go.mod h1:8hdSl6jmveQw8ScByd3AaNHNk51RhbTazdqtTty+NFw=
 github.com/fatih/color v1.7.0/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5KwzbycvMj4=
 github.com/fatih/color v1.10.0 h1:s36xzo75JdqLaaWoiEHk767eHiwo0598uUxyfiPkDsg=
 github.com/fatih/color v1.10.0/go.mod h1:ELkj/draVOlAH/xkhN6mQ50Qd0MPOk5AAr3maGEBuJM=
@@ -52,8 +52,8 @@ github.com/go-playground/locales v0.13.0/go.mod h1:taPMhCMXrRLJO55olJkUXHZBHCxTM
 github.com/go-playground/universal-translator v0.17.0/go.mod h1:UkSxE5sNxxRwHyU+Scu5vgOQjsIJAF8j9muTVoKLVtA=
 github.com/go-playground/validator/v10 v10.4.1/go.mod h1:nlOn6nFhuKACm19sB/8EGNn9GlaMV7XkbRSipzJ0Ii4=
 github.com/go-stack/stack v1.8.0/go.mod h1:v0f6uXyyMGvRgIKkXu+yp6POWl0qKG85gN/melR3HDY=
-github.com/goccy/go-yaml v1.8.8 h1:MGfRB1GeSn/hWXYWS2Pt67iC2GJNnebdIro01ddyucA=
+github.com/goccy/go-yaml v1.8.4 h1:AOEdR7aQgbgwHznGe3BLkDQVujxCPUpHOZZcQcp8Y3M=
-github.com/goccy/go-yaml v1.8.8/go.mod h1:U/jl18uSupI5rdI2jmuCswEA2htH9eXfferR3KfscvA=
+github.com/goccy/go-yaml v1.8.4/go.mod h1:U/jl18uSupI5rdI2jmuCswEA2htH9eXfferR3KfscvA=
 github.com/gogo/protobuf v1.1.1/go.mod h1:r8qH/GZQm5c6nD/R0oafs1akxWv10x8SbQlK7atdtwQ=
 github.com/gogo/protobuf v1.2.1/go.mod h1:hp+jE20tsWTFYpLwKvXlhS1hjn+gTNwPg2I6zVXpSg4=
 github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfUlaOkMMuAQtPIUF8ecWP5IEl/CR7VP2Q=
@@ -101,8 +101,8 @@ github.com/hashicorp/memberlist v0.1.3/go.mod h1:ajVTdAv/9Im8oMAAj5G31PhhMCZJV2p
 github.com/hashicorp/serf v0.8.2/go.mod h1:6hOLApaqBFA1NXqRQAsxw9QxuDEvNxSQRwA/JwenrHc=
 github.com/inconshreveable/mousetrap v1.0.0 h1:Z8tu5sraLXCXIcARxBp/8cbvlwVa7Z1NHg9XEKhtSvM=
 github.com/inconshreveable/mousetrap v1.0.0/go.mod h1:PxqpIevigyE2G7u3NXJIT2ANytuPF1OarO4DADm73n8=
-github.com/jinzhu/copier v0.2.3 h1:Oe09ju+9qft7TffZ7l/04AB2f8u1+V4ZMxmp/nnqeOs=
+github.com/jinzhu/copier v0.1.0 h1:Vh8xALtH3rrKGB/XIRe5d0yCTHPZFauWPLvdpDAbi88=
-github.com/jinzhu/copier v0.2.3/go.mod h1:24xnZezI2Yqac9J61UC6/dG/k76ttpq0DdJI3QmUvro=
+github.com/jinzhu/copier v0.1.0/go.mod h1:24xnZezI2Yqac9J61UC6/dG/k76ttpq0DdJI3QmUvro=
 github.com/jonboulle/clockwork v0.1.0/go.mod h1:Ii8DK3G1RaLaWxj9trq07+26W01tbo22gdxWY5EU2bo=
 github.com/json-iterator/go v1.1.6/go.mod h1:+SdeFBvtyEkXs7REEP0seUULqWtbJapLOCVDaaPEHmU=
 github.com/jstemmer/go-junit-report v0.0.0-20190106144839-af01ea7f8024/go.mod h1:6v2b51hI/fHJwM22ozAgKL4VKDeJcHhJFhtBdhmNjmU=
@@ -182,8 +182,6 @@ github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXf
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
-github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
-github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/subosito/gotenv v1.2.0/go.mod h1:N0PQaV/YGNqwC0u51sEeR/aUtSLEXKX9iv69rRypqCw=
 github.com/timtadh/data-structures v0.5.3 h1:F2tEjoG9qWIyUjbvXVgJqEOGJPMIiYn7U5W5mE+i/vQ=
 github.com/timtadh/data-structures v0.5.3/go.mod h1:9R4XODhJ8JdWFEI8P/HJKqxuJctfBQw6fDibMQny2oU=
@@ -259,8 +257,8 @@ golang.org/x/sys v0.0.0-20190624142023-c5567b49c5d0/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20200116001909-b77594299b42/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae h1:/WDfKMnPU+m5M4xB+6x4kaepxRw6jWvR5iDRdvjHgy8=
 golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210124154548-22da62e12c0c h1:VwygUrnw9jn88c4u8GD3rZQbqrP/tgas88tPUbBxQrk=
+golang.org/x/sys v0.0.0-20210105210732-16f7687f5001 h1:/dSxr6gT0FNI1MO5WLJo8mTmItROeOKTkDn+7OwWBos=
-golang.org/x/sys v0.0.0-20210124154548-22da62e12c0c/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210105210732-16f7687f5001/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.1-0.20180807135948-17ff2d5776d2/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
@@ -326,7 +324,6 @@ gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.4/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.8 h1:obN1ZagJSUGI0Ek/LBmuj4SNLPfIny3KsKFopxRdj10=
 gopkg.in/yaml.v2 v2.2.8/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
-gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b h1:h8qDotaEPuJATrMmW04NCwg7v22aHH28wwpauUhK9Oo=
 gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 honnef.co/go/tools v0.0.0-20190102054323-c2f93a96b099/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=

pkg/yqlib/all_at_once_evaluator.go

@@ -39,11 +39,7 @@ func (e *allAtOnceEvaluator) EvaluateCandidateNodes(expression string, inputCand
 	if err != nil {
 		return nil, err
 	}
-	context, err := e.treeNavigator.GetMatchingNodes(Context{MatchingNodes: inputCandidates}, node)
+	return e.treeNavigator.GetMatchingNodes(inputCandidates, node)
-	if err != nil {
-		return nil, err
-	}
-	return context.MatchingNodes, nil
 }
 
 func (e *allAtOnceEvaluator) EvaluateFiles(expression string, filenames []string, printer Printer) error {

pkg/yqlib/candidate_node.go

@@ -2,6 +2,8 @@ package yqlib
 
 import (
 	"fmt"
+	"strconv"
+	"strings"
 
 	"github.com/jinzhu/copier"
 	yaml "gopkg.in/yaml.v3"
@@ -13,18 +15,10 @@ type CandidateNode struct {
 	Document  uint          // the document index of this node
 	Filename  string
 	FileIndex int
-	// when performing op against all nodes given, this will treat all the nodes as one
-	// (e.g. top level cross document merge). This property does not propegate to child nodes.
-	EvaluateTogether bool
-	IsMapKey         bool
 }
 
 func (n *CandidateNode) GetKey() string {
-	keyPrefix := ""
+	return fmt.Sprintf("%v - %v", n.Document, n.Path)
-	if n.IsMapKey {
-		keyPrefix = "key-"
-	}
-	return fmt.Sprintf("%v%v - %v", keyPrefix, n.Document, n.Path)
 }
 
 func (n *CandidateNode) CreateChild(path interface{}, node *yaml.Node) *CandidateNode {
@@ -66,10 +60,11 @@ func (n *CandidateNode) UpdateFrom(other *CandidateNode) {
 	n.UpdateAttributesFrom(other)
 	n.Node.Content = other.Node.Content
 	n.Node.Value = other.Node.Value
+	n.Node.Alias = other.Node.Alias
+	n.Node.Anchor = other.Node.Anchor
 }
 
 func (n *CandidateNode) UpdateAttributesFrom(other *CandidateNode) {
-	log.Debug("UpdateAttributesFrom: n: %v other: %v", n.GetKey(), other.GetKey())
 	if n.Node.Kind != other.Node.Kind {
 		// clear out the contents when switching to a different type
 		// e.g. map to array
@@ -78,8 +73,6 @@ func (n *CandidateNode) UpdateAttributesFrom(other *CandidateNode) {
 	}
 	n.Node.Kind = other.Node.Kind
 	n.Node.Tag = other.Node.Tag
-	n.Node.Alias = other.Node.Alias
-	n.Node.Anchor = other.Node.Anchor
 
 	// merge will pickup the style of the new thing
 	// when autocreating nodes
@@ -90,3 +83,46 @@ func (n *CandidateNode) UpdateAttributesFrom(other *CandidateNode) {
 	n.Node.HeadComment = n.Node.HeadComment + other.Node.HeadComment
 	n.Node.LineComment = n.Node.LineComment + other.Node.LineComment
 }
+
+func (n *CandidateNode) PathStackToString() string {
+	return mergePathStackToString(n.Path)
+}
+
+func mergePathStackToString(pathStack []interface{}) string {
+	var sb strings.Builder
+	for index, path := range pathStack {
+		switch path.(type) {
+		case int, int64:
+			// if arrayMergeStrategy == AppendArrayMergeStrategy {
+			// sb.WriteString("[+]")
+			// } else {
+			sb.WriteString(fmt.Sprintf("[%v]", path))
+			// }
+
+		default:
+			s := fmt.Sprintf("%v", path)
+			var _, errParsingInt = strconv.ParseInt(s, 10, 64) // nolint
+
+			hasSpecial := strings.Contains(s, ".") || strings.Contains(s, "[") || strings.Contains(s, "]") || strings.Contains(s, "\"")
+			hasDoubleQuotes := strings.Contains(s, "\"")
+			wrappingCharacterStart := "\""
+			wrappingCharacterEnd := "\""
+			if hasDoubleQuotes {
+				wrappingCharacterStart = "("
+				wrappingCharacterEnd = ")"
+			}
+			if hasSpecial || errParsingInt == nil {
+				sb.WriteString(wrappingCharacterStart)
+			}
+			sb.WriteString(s)
+			if hasSpecial || errParsingInt == nil {
+				sb.WriteString(wrappingCharacterEnd)
+			}
+		}
+
+		if index < len(pathStack)-1 {
+			sb.WriteString(".")
+		}
+	}
+	return sb.String()
+}

pkg/yqlib/context.go

@@ -1,54 +0,0 @@
-package yqlib
-
-import (
-	"container/list"
-
-	"github.com/jinzhu/copier"
-)
-
-type Context struct {
-	MatchingNodes  *list.List
-	Variables      map[string]*list.List
-	DontAutoCreate bool
-}
-
-func (n *Context) SingleChildContext(candidate *CandidateNode) Context {
-	list := list.New()
-	list.PushBack(candidate)
-	return n.ChildContext(list)
-}
-
-func (n *Context) GetVariable(name string) *list.List {
-	if n.Variables == nil {
-		return nil
-	}
-	return n.Variables[name]
-}
-
-func (n *Context) SetVariable(name string, value *list.List) {
-	if n.Variables == nil {
-		n.Variables = make(map[string]*list.List)
-	}
-	n.Variables[name] = value
-}
-
-func (n *Context) ChildContext(results *list.List) Context {
-	clone := Context{}
-	err := copier.Copy(&clone, n)
-	if err != nil {
-		log.Error("Error cloning context :(")
-		panic(err)
-	}
-	clone.MatchingNodes = results
-	return clone
-}
-
-func (n *Context) Clone() Context {
-	clone := Context{}
-	err := copier.Copy(&clone, n)
-	if err != nil {
-		log.Error("Error cloning context :(")
-		panic(err)
-	}
-	return clone
-}

pkg/yqlib/data_tree_navigator.go

@@ -3,14 +3,16 @@ package yqlib
 import (
 	"fmt"
 
+	"container/list"
+
 	logging "gopkg.in/op/go-logging.v1"
 )
 
 type DataTreeNavigator interface {
-	// given the context and a expressionNode,
+	// given a list of CandidateEntities and a expressionNode,
-	// this will process the against the given expressionNode and return
+	// this will process the list against the given expressionNode and return
-	// a new context of matching candidates
+	// a new list of matching candidates
-	GetMatchingNodes(context Context, expressionNode *ExpressionNode) (Context, error)
+	GetMatchingNodes(matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error)
 }
 
 type dataTreeNavigator struct {
@@ -20,22 +22,22 @@ func NewDataTreeNavigator() DataTreeNavigator {
 	return &dataTreeNavigator{}
 }
 
-func (d *dataTreeNavigator) GetMatchingNodes(context Context, expressionNode *ExpressionNode) (Context, error) {
+func (d *dataTreeNavigator) GetMatchingNodes(matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	if expressionNode == nil {
 		log.Debugf("getMatchingNodes - nothing to do")
-		return context, nil
+		return matchingNodes, nil
 	}
 	log.Debugf("Processing Op: %v", expressionNode.Operation.toString())
 	if log.IsEnabledFor(logging.DEBUG) {
-		for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+		for el := matchingNodes.Front(); el != nil; el = el.Next() {
 			log.Debug(NodeToString(el.Value.(*CandidateNode)))
 		}
 	}
 	log.Debug(">>")
 	handler := expressionNode.Operation.OperationType.Handler
 	if handler != nil {
-		return handler(d, context, expressionNode)
+		return handler(d, matchingNodes, expressionNode)
 	}
-	return Context{}, fmt.Errorf("Unknown operator %v", expressionNode.Operation.OperationType)
+	return nil, fmt.Errorf("Unknown operator %v", expressionNode.Operation.OperationType)
 
 }

pkg/yqlib/doc/Add.md

@@ -209,15 +209,3 @@ will output
 a: 4
 ```
 
-## Add to null
-Adding to null simply returns the rhs
-
-Running
-```bash
-yq eval --null-input 'null + "cat"'
-```
-will output
-```yaml
-cat
-```
-

pkg/yqlib/doc/Equals.md

@@ -29,24 +29,6 @@ true
 false
 ```
 
-## Don't match string
-Given a sample.yml file of:
-```yaml
-- cat
-- goat
-- dog
-```
-then
-```bash
-yq eval '.[] | (. != "*at")' sample.yml
-```
-will output
-```yaml
-false
-false
-true
-```
-
 ## Match number
 Given a sample.yml file of:
 ```yaml
@@ -65,24 +47,6 @@ true
 false
 ```
 
-## Dont match number
-Given a sample.yml file of:
-```yaml
-- 3
-- 4
-- 5
-```
-then
-```bash
-yq eval '.[] | (. != 4)' sample.yml
-```
-will output
-```yaml
-true
-false
-true
-```
-
 ## Match nulls
 Running
 ```bash

pkg/yqlib/doc/Length.md

@@ -16,20 +16,6 @@ will output
 3
 ```
 
-## null length
-Given a sample.yml file of:
-```yaml
-a: null
-```
-then
-```bash
-yq eval '.a | length' sample.yml
-```
-will output
-```yaml
-0
-```
-
 ## Map length
 returns number of entries
 

pkg/yqlib/doc/Multiply.md

@@ -1,14 +1,13 @@
-Like the multiple operator in jq, depending on the operands, this multiply operator will do different things. Currently only objects are supported, which have the effect of merging the RHS into the LHS.
+Like the multiple operator in `jq`, depending on the operands, this multiply operator will do different things. Currently only objects are supported, which have the effect of merging the RHS into the LHS.
 
-To concatenate arrays when merging objects, use the *+ form (see examples below). This will recursively merge objects, appending arrays when it encounters them.
+Upcoming versions of `yq` will add support for other types of multiplication (numbers, strings).
+
+To concatenate when merging objects, use the `*+` form (see examples below). This will recursively merge objects, appending arrays when it encounters them.
 
-To merge only existing fields, use the *? form. Note that this can be used with the concatenate arrays too *+?.
 Note that when merging objects, this operator returns the merged object (not the parent). This will be clearer in the examples below.
 
-Multiplication of strings and numbers are not yet supported.
-
 ## Merging files
-Note the use of `eval-all` to ensure all documents are loaded into memory.
+Note the use of eval-all to ensure all documents are loaded into memory.
 
 ```bash
 yq eval-all 'select(fileIndex == 0) * select(fileIndex == 1)' file1.yaml file2.yaml
@@ -71,6 +70,7 @@ Given a sample.yml file of:
 a: {things: great}
 b:
   also: "me"
+
 ```
 then
 ```bash

pkg/yqlib/doc/Traverse.md

@@ -33,7 +33,7 @@ c: banana
 ```
 
 ## Special characters
-Use quotes with brackets around path elements with special characters
+Use quotes around path elements with special characters
 
 Given a sample.yml file of:
 ```yaml
@@ -41,23 +41,7 @@ Given a sample.yml file of:
 ```
 then
 ```bash
-yq eval '.["{}"]' sample.yml
+yq eval '."{}"' sample.yml
-```
-will output
-```yaml
-frog
-```
-
-## Keys with spaces
-Use quotes with brackets around path elements with special characters
-
-Given a sample.yml file of:
-```yaml
-"red rabbit": frog
-```
-then
-```bash
-yq eval '.["red rabbit"]' sample.yml
 ```
 will output
 ```yaml

pkg/yqlib/doc/Variable Operators.md

@@ -1,58 +0,0 @@
-For more complex scenarios, variables can be used to hold values of expression to be used in other expressions.
-
-## Single value variable
-Given a sample.yml file of:
-```yaml
-a: cat
-```
-then
-```bash
-yq eval '.a as $foo | $foo' sample.yml
-```
-will output
-```yaml
-cat
-```
-
-## Multi value variable
-Given a sample.yml file of:
-```yaml
-- cat
-- dog
-```
-then
-```bash
-yq eval '.[] as $foo | $foo' sample.yml
-```
-will output
-```yaml
-cat
-dog
-```
-
-## Using variables as a lookup
-Example taken from [jq](https://stedolan.github.io/jq/manual/#Variable/SymbolicBindingOperator:...as$identifier|...)
-
-Given a sample.yml file of:
-```yaml
-"posts":
-  - "title": Frist psot
-    "author": anon
-  - "title": A well-written article
-    "author": person1
-"realnames":
-  "anon": Anonymous Coward
-  "person1": Person McPherson
-```
-then
-```bash
-yq eval '.realnames as $names | .posts[] | {"title":.title, "author": $names[.author]}' sample.yml
-```
-will output
-```yaml
-title: Frist psot
-author: Anonymous Coward
-title: A well-written article
-author: Person McPherson
-```
-

pkg/yqlib/doc/headers/Multiply.md

@@ -1,14 +1,13 @@
-Like the multiple operator in jq, depending on the operands, this multiply operator will do different things. Currently only objects are supported, which have the effect of merging the RHS into the LHS.
+Like the multiple operator in `jq`, depending on the operands, this multiply operator will do different things. Currently only objects are supported, which have the effect of merging the RHS into the LHS.
 
-To concatenate arrays when merging objects, use the *+ form (see examples below). This will recursively merge objects, appending arrays when it encounters them.
+Upcoming versions of `yq` will add support for other types of multiplication (numbers, strings).
+
+To concatenate when merging objects, use the `*+` form (see examples below). This will recursively merge objects, appending arrays when it encounters them.
 
-To merge only existing fields, use the *? form. Note that this can be used with the concatenate arrays too *+?.
 Note that when merging objects, this operator returns the merged object (not the parent). This will be clearer in the examples below.
 
-Multiplication of strings and numbers are not yet supported.
-
 ## Merging files
-Note the use of `eval-all` to ensure all documents are loaded into memory.
+Note the use of eval-all to ensure all documents are loaded into memory.
 
 ```bash
 yq eval-all 'select(fileIndex == 0) * select(fileIndex == 1)' file1.yaml file2.yaml

pkg/yqlib/doc/headers/Variable Operators.md

@@ -1 +0,0 @@
-For more complex scenarios, variables can be used to hold values of expression to be used in other expressions.

pkg/yqlib/encoder.go

@@ -76,8 +76,6 @@ func mapKeysToStrings(node *yaml.Node) {
 
 func NewJsonEncoder(destination io.Writer, indent int) Encoder {
 	var encoder = json.NewEncoder(destination)
-	encoder.SetEscapeHTML(false) // do not escape html chars e.g. &, <, >
-
 	var indentString = ""
 
 	for index := 0; index < indent; index++ {
@@ -155,15 +153,11 @@ func (o *orderedMap) UnmarshalJSON(data []byte) error {
 }
 
 func (o orderedMap) MarshalJSON() ([]byte, error) {
+	if o.kv == nil {
+		return json.Marshal(o.altVal)
+	}
 	buf := new(bytes.Buffer)
 	enc := json.NewEncoder(buf)
-	enc.SetEscapeHTML(false) // do not escape html chars e.g. &, <, >
-	if o.kv == nil {
-		if err := enc.Encode(o.altVal); err != nil {
-			return nil, err
-		}
-		return buf.Bytes(), nil
-	}
 	buf.WriteByte('{')
 	for idx, el := range o.kv {
 		if err := enc.Encode(el.K); err != nil {

pkg/yqlib/encoder_test.go

@@ -9,11 +9,29 @@ import (
 	"github.com/mikefarah/yq/v4/test"
 )
 
-func yamlToJson(sampleYaml string, indent int) string {
+var sampleYaml = `zabbix: winner
+apple: great
+banana:
+- {cobra: kai, angus: bob}
+`
+
+var expectedJson = `{
+  "zabbix": "winner",
+  "apple": "great",
+  "banana": [
+    {
+      "cobra": "kai",
+      "angus": "bob"
+    }
+  ]
+}
+`
+
+func TestJsonEncoderPreservesObjectOrder(t *testing.T) {
 	var output bytes.Buffer
 	writer := bufio.NewWriter(&output)
 
-	var jsonEncoder = NewJsonEncoder(writer, indent)
+	var jsonEncoder = NewJsonEncoder(writer, 2)
 	inputs, err := readDocuments(strings.NewReader(sampleYaml), "sample.yml", 0)
 	if err != nil {
 		panic(err)
@@ -24,33 +42,6 @@ func yamlToJson(sampleYaml string, indent int) string {
 		panic(err)
 	}
 	writer.Flush()
+	test.AssertResult(t, expectedJson, output.String())
 
-	return strings.TrimSuffix(output.String(), "\n")
-}
-
-func TestJsonEncoderPreservesObjectOrder(t *testing.T) {
-	var sampleYaml = `zabbix: winner
-apple: great
-banana:
-- {cobra: kai, angus: bob}
-`
-	var expectedJson = `{
-  "zabbix": "winner",
-  "apple": "great",
-  "banana": [
-    {
-      "cobra": "kai",
-      "angus": "bob"
-    }
-  ]
-}`
-	var actualJson = yamlToJson(sampleYaml, 2)
-	test.AssertResult(t, expectedJson, actualJson)
-}
-
-func TestJsonEncoderDoesNotEscapeHTMLChars(t *testing.T) {
-	var sampleYaml = `build: "( ./lint && ./format && ./compile ) < src.code"`
-	var expectedJson = `{"build":"( ./lint && ./format && ./compile ) < src.code"}`
-	var actualJson = yamlToJson(sampleYaml, 0)
-	test.AssertResult(t, expectedJson, actualJson)
 }

pkg/yqlib/expression_parser.go

@@ -70,7 +70,7 @@ func (p *expressionParserImpl) createExpressionTree(postFixPath []*Operation) (*
 		stack = append(stack, &newNode)
 	}
 	if len(stack) != 1 {
-		return nil, fmt.Errorf("Bad expression, please check expression syntax")
+		return nil, fmt.Errorf("expected end of expression but found '%v', please check expression syntax", strings.TrimSpace(stack[1].Operation.StringValue))
 	}
 	return stack[0], nil
 }

pkg/yqlib/expression_parser_test.go

@@ -38,5 +38,5 @@ func TestPathTreeOneArgForOneArgOp(t *testing.T) {
 
 func TestPathTreeExtraArgs(t *testing.T) {
 	_, err := NewExpressionParser().ParseExpression("sortKeys(.) explode(.)")
-	test.AssertResultComplex(t, "Bad expression, please check expression syntax", err.Error())
+	test.AssertResultComplex(t, "expected end of expression but found 'explode', please check expression syntax", err.Error())
 }

pkg/yqlib/expression_postfix.go

@@ -20,22 +20,20 @@ func newExpressionPostFixer() expressionPostFixer {
 func popOpToResult(opStack []*token, result []*Operation) ([]*token, []*Operation) {
 	var newOp *token
 	opStack, newOp = opStack[0:len(opStack)-1], opStack[len(opStack)-1]
-	log.Debugf("popped %v from opstack to results", newOp.toString(true))
 	return opStack, append(result, newOp.Operation)
 }
 
 func (p *expressionPostFixerImpl) ConvertToPostfix(infixTokens []*token) ([]*Operation, error) {
 	var result []*Operation
-	// surround the whole thing with brackets
+	// surround the whole thing with quotes
-	var opStack = []*token{{TokenType: openBracket}}
+	var opStack = []*token{&token{TokenType: openBracket}}
 	var tokens = append(infixTokens, &token{TokenType: closeBracket})
 
 	for _, currentToken := range tokens {
-		log.Debugf("postfix processing currentToken %v", currentToken.toString(true))
+		log.Debugf("postfix processing currentToken %v, %v", currentToken.toString(), currentToken.Operation)
 		switch currentToken.TokenType {
 		case openBracket, openCollect, openCollectObject:
 			opStack = append(opStack, currentToken)
-			log.Debugf("put %v onto the opstack", currentToken.toString(true))
 		case closeCollect, closeCollectObject:
 			var opener tokenType = openCollect
 			var collectOperator *operationType = collectOpType
@@ -43,23 +41,23 @@ func (p *expressionPostFixerImpl) ConvertToPostfix(infixTokens []*token) ([]*Ope
 				opener = openCollectObject
 				collectOperator = collectObjectOpType
 			}
-
+			itemsInMiddle := false
 			for len(opStack) > 0 && opStack[len(opStack)-1].TokenType != opener {
 				opStack, result = popOpToResult(opStack, result)
+				itemsInMiddle = true
+			}
+			if !itemsInMiddle {
+				// must be an empty collection, add the empty object as a LHS parameter
+				result = append(result, &Operation{OperationType: emptyOpType})
 			}
 			if len(opStack) == 0 {
 				return nil, errors.New("Bad path expression, got close collect brackets without matching opening bracket")
 			}
-			// now we should have [ as the last element on the opStack, get rid of it
+			// now we should have [] as the last element on the opStack, get rid of it
 			opStack = opStack[0 : len(opStack)-1]
-			log.Debugf("deleteing open bracket from opstack")
-
 			//and append a collect to the opStack
-			result = append(result, &Operation{OperationType: collectOperator})
+			opStack = append(opStack, &token{TokenType: operationToken, Operation: &Operation{OperationType: shortPipeOpType}})
-			log.Debugf("put collect onto the result")
+			opStack = append(opStack, &token{TokenType: operationToken, Operation: &Operation{OperationType: collectOperator}})
-			result = append(result, &Operation{OperationType: shortPipeOpType})
-			log.Debugf("put shortpipe onto the result")
-
 		case closeBracket:
 			for len(opStack) > 0 && opStack[len(opStack)-1].TokenType != openBracket {
 				opStack, result = popOpToResult(opStack, result)
@@ -75,12 +73,11 @@ func (p *expressionPostFixerImpl) ConvertToPostfix(infixTokens []*token) ([]*Ope
 			// pop off higher precedent operators onto the result
 			for len(opStack) > 0 &&
 				opStack[len(opStack)-1].TokenType == operationToken &&
-				opStack[len(opStack)-1].Operation.OperationType.Precedence > currentPrecedence {
+				opStack[len(opStack)-1].Operation.OperationType.Precedence >= currentPrecedence {
 				opStack, result = popOpToResult(opStack, result)
 			}
 			// add this operator to the opStack
 			opStack = append(opStack, currentToken)
-			log.Debugf("put %v onto the opstack", currentToken.toString(true))
 		}
 	}
 

pkg/yqlib/expression_processing_test.go

@@ -12,70 +12,40 @@ var pathTests = []struct {
 	expectedTokens  []interface{}
 	expectedPostFix []interface{}
 }{
-	{
-		`.a as $item ireduce (0; . + $item)`, // note - add code to shuffle reduce to this position for postfix
-		append(make([]interface{}, 0), "a", "ASSIGN_VARIABLE", "GET_VARIABLE", "REDUCE", "(", "0 (int64)", "BLOCK", "SELF", "ADD", "GET_VARIABLE", ")"),
-		append(make([]interface{}, 0), "a", "GET_VARIABLE", "ASSIGN_VARIABLE", "0 (int64)", "SELF", "GET_VARIABLE", "ADD", "BLOCK", "REDUCE"),
-	},
-	{
-		`.a | .b | .c`,
-		append(make([]interface{}, 0), "a", "PIPE", "b", "PIPE", "c"),
-		append(make([]interface{}, 0), "a", "b", "c", "PIPE", "PIPE"),
-	},
 	{
 		`[]`,
-		append(make([]interface{}, 0), "[", "EMPTY", "]"),
+		append(make([]interface{}, 0), "[", "]"),
 		append(make([]interface{}, 0), "EMPTY", "COLLECT", "SHORT_PIPE"),
 	},
-	{
-		`{}`,
-		append(make([]interface{}, 0), "{", "EMPTY", "}"),
-		append(make([]interface{}, 0), "EMPTY", "COLLECT_OBJECT", "SHORT_PIPE"),
-	},
-	{
-		`[{}]`,
-		append(make([]interface{}, 0), "[", "{", "EMPTY", "}", "]"),
-		append(make([]interface{}, 0), "EMPTY", "COLLECT_OBJECT", "SHORT_PIPE", "COLLECT", "SHORT_PIPE"),
-	},
-	{
-		`.realnames as $names | $names["anon"]`,
-		append(make([]interface{}, 0), "realnames", "ASSIGN_VARIABLE", "GET_VARIABLE", "PIPE", "GET_VARIABLE", "TRAVERSE_ARRAY", "[", "anon (string)", "]"),
-		append(make([]interface{}, 0), "realnames", "GET_VARIABLE", "ASSIGN_VARIABLE", "GET_VARIABLE", "anon (string)", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY", "PIPE"),
-	},
-	{
-		`.b[.a]`,
-		append(make([]interface{}, 0), "b", "TRAVERSE_ARRAY", "[", "a", "]"),
-		append(make([]interface{}, 0), "b", "a", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY"),
-	},
 	{
 		`.[]`,
-		append(make([]interface{}, 0), "SELF", "TRAVERSE_ARRAY", "[", "EMPTY", "]"),
+		append(make([]interface{}, 0), "TRAVERSE_ARRAY", "[", "]"),
-		append(make([]interface{}, 0), "SELF", "EMPTY", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY"),
+		append(make([]interface{}, 0), "EMPTY", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY"),
 	},
 	{
 		`.a[]`,
-		append(make([]interface{}, 0), "a", "TRAVERSE_ARRAY", "[", "EMPTY", "]"),
+		append(make([]interface{}, 0), "a", "SHORT_PIPE", "TRAVERSE_ARRAY", "[", "]"),
-		append(make([]interface{}, 0), "a", "EMPTY", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY"),
+		append(make([]interface{}, 0), "a", "EMPTY", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY", "SHORT_PIPE"),
 	},
 	{
 		`.a.[]`,
-		append(make([]interface{}, 0), "a", "TRAVERSE_ARRAY", "[", "EMPTY", "]"),
+		append(make([]interface{}, 0), "a", "SHORT_PIPE", "TRAVERSE_ARRAY", "[", "]"),
-		append(make([]interface{}, 0), "a", "EMPTY", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY"),
+		append(make([]interface{}, 0), "a", "EMPTY", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY", "SHORT_PIPE"),
 	},
 	{
 		`.a[0]`,
-		append(make([]interface{}, 0), "a", "TRAVERSE_ARRAY", "[", "0 (int64)", "]"),
+		append(make([]interface{}, 0), "a", "SHORT_PIPE", "TRAVERSE_ARRAY", "[", "0 (int64)", "]"),
-		append(make([]interface{}, 0), "a", "0 (int64)", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY"),
+		append(make([]interface{}, 0), "a", "0 (int64)", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY", "SHORT_PIPE"),
 	},
 	{
 		`.a.[0]`,
-		append(make([]interface{}, 0), "a", "TRAVERSE_ARRAY", "[", "0 (int64)", "]"),
+		append(make([]interface{}, 0), "a", "SHORT_PIPE", "TRAVERSE_ARRAY", "[", "0 (int64)", "]"),
-		append(make([]interface{}, 0), "a", "0 (int64)", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY"),
+		append(make([]interface{}, 0), "a", "0 (int64)", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY", "SHORT_PIPE"),
 	},
 	{
 		`.a[].c`,
-		append(make([]interface{}, 0), "a", "TRAVERSE_ARRAY", "[", "EMPTY", "]", "SHORT_PIPE", "c"),
+		append(make([]interface{}, 0), "a", "SHORT_PIPE", "TRAVERSE_ARRAY", "[", "]", "SHORT_PIPE", "c"),
-		append(make([]interface{}, 0), "a", "EMPTY", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY", "c", "SHORT_PIPE"),
+		append(make([]interface{}, 0), "a", "EMPTY", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY", "SHORT_PIPE", "c", "SHORT_PIPE"),
 	},
 	{
 		`[3]`,
@@ -99,18 +69,18 @@ var pathTests = []struct {
 	},
 	{
 		`.a | .[].b == "apple"`,
-		append(make([]interface{}, 0), "a", "PIPE", "SELF", "TRAVERSE_ARRAY", "[", "EMPTY", "]", "SHORT_PIPE", "b", "EQUALS", "apple (string)"),
+		append(make([]interface{}, 0), "a", "PIPE", "TRAVERSE_ARRAY", "[", "]", "SHORT_PIPE", "b", "EQUALS", "apple (string)"),
-		append(make([]interface{}, 0), "a", "SELF", "EMPTY", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY", "b", "SHORT_PIPE", "apple (string)", "EQUALS", "PIPE"),
+		append(make([]interface{}, 0), "a", "EMPTY", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY", "b", "SHORT_PIPE", "apple (string)", "EQUALS", "PIPE"),
 	},
 	{
 		`(.a | .[].b) == "apple"`,
-		append(make([]interface{}, 0), "(", "a", "PIPE", "SELF", "TRAVERSE_ARRAY", "[", "EMPTY", "]", "SHORT_PIPE", "b", ")", "EQUALS", "apple (string)"),
+		append(make([]interface{}, 0), "(", "a", "PIPE", "TRAVERSE_ARRAY", "[", "]", "SHORT_PIPE", "b", ")", "EQUALS", "apple (string)"),
-		append(make([]interface{}, 0), "a", "SELF", "EMPTY", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY", "b", "SHORT_PIPE", "PIPE", "apple (string)", "EQUALS"),
+		append(make([]interface{}, 0), "a", "EMPTY", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY", "b", "SHORT_PIPE", "PIPE", "apple (string)", "EQUALS"),
 	},
 	{
 		`.[] | select(. == "*at")`,
-		append(make([]interface{}, 0), "SELF", "TRAVERSE_ARRAY", "[", "EMPTY", "]", "PIPE", "SELECT", "(", "SELF", "EQUALS", "*at (string)", ")"),
+		append(make([]interface{}, 0), "TRAVERSE_ARRAY", "[", "]", "PIPE", "SELECT", "(", "SELF", "EQUALS", "*at (string)", ")"),
-		append(make([]interface{}, 0), "SELF", "EMPTY", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY", "SELF", "*at (string)", "EQUALS", "SELECT", "PIPE"),
+		append(make([]interface{}, 0), "EMPTY", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY", "SELF", "*at (string)", "EQUALS", "SELECT", "PIPE"),
 	},
 	{
 		`[true]`,
@@ -143,9 +113,9 @@ var pathTests = []struct {
 		append(make([]interface{}, 0), "a", "mike (string)", "CREATE_MAP", "COLLECT_OBJECT", "SHORT_PIPE"),
 	},
 	{
-		`{.a: .c, .b.[]: .f.g[]}`,
+		`{.a: .c, .b.[]: .f.g.[]}`,
-		append(make([]interface{}, 0), "{", "a", "CREATE_MAP", "c", "UNION", "b", "TRAVERSE_ARRAY", "[", "EMPTY", "]", "CREATE_MAP", "f", "SHORT_PIPE", "g", "TRAVERSE_ARRAY", "[", "EMPTY", "]", "}"),
+		append(make([]interface{}, 0), "{", "a", "CREATE_MAP", "c", "UNION", "b", "SHORT_PIPE", "TRAVERSE_ARRAY", "[", "]", "CREATE_MAP", "f", "SHORT_PIPE", "g", "SHORT_PIPE", "TRAVERSE_ARRAY", "[", "]", "}"),
-		append(make([]interface{}, 0), "a", "c", "CREATE_MAP", "b", "EMPTY", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY", "f", "g", "EMPTY", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY", "SHORT_PIPE", "CREATE_MAP", "UNION", "COLLECT_OBJECT", "SHORT_PIPE"),
+		append(make([]interface{}, 0), "a", "c", "CREATE_MAP", "b", "EMPTY", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY", "SHORT_PIPE", "f", "g", "SHORT_PIPE", "EMPTY", "COLLECT", "SHORT_PIPE", "TRAVERSE_ARRAY", "SHORT_PIPE", "CREATE_MAP", "UNION", "COLLECT_OBJECT", "SHORT_PIPE"),
 	},
 	{
 		`explode(.a.b)`,
@@ -197,6 +167,11 @@ var pathTests = []struct {
 		append(make([]interface{}, 0), "foo*", "PIPE", "(", "SELF", "ASSIGN_STYLE", "flow (string)", ")"),
 		append(make([]interface{}, 0), "foo*", "SELF", "flow (string)", "ASSIGN_STYLE", "PIPE"),
 	},
+	{
+		`{}`,
+		append(make([]interface{}, 0), "{", "}"),
+		append(make([]interface{}, 0), "EMPTY", "COLLECT_OBJECT", "SHORT_PIPE"),
+	},
 }
 
 var tokeniser = newExpressionTokeniser()
@@ -210,7 +185,7 @@ func TestPathParsing(t *testing.T) {
 		}
 		var tokenValues []interface{}
 		for _, token := range tokens {
-			tokenValues = append(tokenValues, token.toString(false))
+			tokenValues = append(tokenValues, token.toString())
 		}
 		test.AssertResultComplexWithContext(t, tt.expectedTokens, tokenValues, fmt.Sprintf("tokenise: %v", tt.path))
 

pkg/yqlib/expression_tokeniser.go

@@ -34,11 +34,9 @@ type token struct {
 
 }
 
-func (t *token) toString(detail bool) string {
+func (t *token) toString() string {
 	if t.TokenType == operationToken {
-		if detail {
+		log.Debug("toString, its an op")
-			return fmt.Sprintf("%v (%v)", t.Operation.toString(), t.Operation.OperationType.Precedence)
-		}
 		return t.Operation.toString()
 	} else if t.TokenType == openBracket {
 		return "("
@@ -182,19 +180,6 @@ func stringValue(wrapped bool) lex.Action {
 	}
 }
 
-func getVariableOpToken() lex.Action {
-	return func(s *lex.Scanner, m *machines.Match) (interface{}, error) {
-		value := string(m.Bytes)
-
-		value = value[1 : len(value)-1]
-
-		getVarOperation := createValueOperation(value, value)
-		getVarOperation.OperationType = getVariableOpType
-
-		return &token{TokenType: operationToken, Operation: getVarOperation, CheckForPostTraverse: true}, nil
-	}
-}
-
 func envOp(strenv bool) lex.Action {
 	return func(s *lex.Scanner, m *machines.Match) (interface{}, error) {
 		value := string(m.Bytes)
@@ -252,8 +237,6 @@ func initLexer() (*lex.Lexer, error) {
 	lexer.Add([]byte(`or`), opToken(orOpType))
 	lexer.Add([]byte(`and`), opToken(andOpType))
 	lexer.Add([]byte(`not`), opToken(notOpType))
-	lexer.Add([]byte(`ireduce`), opToken(reduceOpType))
-	lexer.Add([]byte(`;`), opToken(blockOpType))
 	lexer.Add([]byte(`\/\/`), opToken(alternativeOpType))
 
 	lexer.Add([]byte(`documentIndex`), opToken(getDocumentIndexOpType))
@@ -286,7 +269,6 @@ func initLexer() (*lex.Lexer, error) {
 	lexer.Add([]byte(`collect`), opToken(collectOpType))
 
 	lexer.Add([]byte(`\s*==\s*`), opToken(equalsOpType))
-	lexer.Add([]byte(`\s*!=\s*`), opToken(notEqualsOpType))
 	lexer.Add([]byte(`\s*=\s*`), assignOpToken(false))
 
 	lexer.Add([]byte(`del`), opToken(deleteChildOpType))
@@ -322,8 +304,6 @@ func initLexer() (*lex.Lexer, error) {
 	lexer.Add([]byte(`\*[\+|\?]*`), multiplyWithPrefs())
 	lexer.Add([]byte(`\+`), opToken(addOpType))
 	lexer.Add([]byte(`\+=`), opToken(addAssignOpType))
-	lexer.Add([]byte(`\$[a-zA-Z_-0-9]+`), getVariableOpToken())
-	lexer.Add([]byte(`as`), opToken(assignVariableOpType))
 
 	err := lexer.Compile()
 	if err != nil {
@@ -359,7 +339,7 @@ func (p *expressionTokeniserImpl) Tokenise(expression string) ([]*token, error)
 
 		if tok != nil {
 			currentToken := tok.(*token)
-			log.Debugf("Tokenising %v", currentToken.toString(true))
+			log.Debugf("Tokenising %v", currentToken.toString())
 			tokens = append(tokens, currentToken)
 		}
 		if err != nil {
@@ -389,12 +369,6 @@ func (p *expressionTokeniserImpl) handleToken(tokens []*token, index int, postPr
 		//need to put a traverse array then a collect currentToken
 		// do this by adding traverse then converting currentToken to collect
 
-		if index == 0 || tokens[index-1].TokenType != operationToken ||
-			tokens[index-1].Operation.OperationType != traversePathOpType {
-			op := &Operation{OperationType: selfReferenceOpType, StringValue: "SELF"}
-			postProcessedTokens = append(postProcessedTokens, &token{TokenType: operationToken, Operation: op})
-		}
-
 		op := &Operation{OperationType: traverseArrayOpType, StringValue: "TRAVERSE_ARRAY"}
 		postProcessedTokens = append(postProcessedTokens, &token{TokenType: operationToken, Operation: op})
 
@@ -412,14 +386,6 @@ func (p *expressionTokeniserImpl) handleToken(tokens []*token, index int, postPr
 
 	postProcessedTokens = append(postProcessedTokens, currentToken)
 
-	if index != len(tokens)-1 &&
-		((currentToken.TokenType == openCollect && tokens[index+1].TokenType == closeCollect) ||
-			(currentToken.TokenType == openCollectObject && tokens[index+1].TokenType == closeCollectObject)) {
-
-		op := &Operation{OperationType: emptyOpType, StringValue: "EMPTY"}
-		postProcessedTokens = append(postProcessedTokens, &token{TokenType: operationToken, Operation: op})
-	}
-
 	if index != len(tokens)-1 && currentToken.CheckForPostTraverse &&
 		tokens[index+1].TokenType == operationToken &&
 		tokens[index+1].Operation.OperationType == traversePathOpType {
@@ -429,8 +395,18 @@ func (p *expressionTokeniserImpl) handleToken(tokens []*token, index int, postPr
 	if index != len(tokens)-1 && currentToken.CheckForPostTraverse &&
 		tokens[index+1].TokenType == openCollect {
 
-		op := &Operation{OperationType: traverseArrayOpType}
+		op := &Operation{OperationType: shortPipeOpType, Value: "PIPE"}
 		postProcessedTokens = append(postProcessedTokens, &token{TokenType: operationToken, Operation: op})
+
+		op = &Operation{OperationType: traverseArrayOpType}
+		postProcessedTokens = append(postProcessedTokens, &token{TokenType: operationToken, Operation: op})
+	}
+	if index != len(tokens)-1 && currentToken.CheckForPostTraverse &&
+		tokens[index+1].TokenType == traverseArrayCollect {
+
+		op := &Operation{OperationType: shortPipeOpType, Value: "PIPE"}
+		postProcessedTokens = append(postProcessedTokens, &token{TokenType: operationToken, Operation: op})
+
 	}
 	return postProcessedTokens, skipNextToken
 }

pkg/yqlib/lib.go

@@ -25,9 +25,6 @@ type operationType struct {
 
 var orOpType = &operationType{Type: "OR", NumArgs: 2, Precedence: 20, Handler: orOperator}
 var andOpType = &operationType{Type: "AND", NumArgs: 2, Precedence: 20, Handler: andOperator}
-var reduceOpType = &operationType{Type: "REDUCE", NumArgs: 2, Precedence: 5, Handler: reduceOperator}
-
-var blockOpType = &operationType{Type: "BLOCK", Precedence: 10, NumArgs: 2, Handler: emptyOperator}
 
 var unionOpType = &operationType{Type: "UNION", NumArgs: 2, Precedence: 10, Handler: unionOperator}
 
@@ -38,7 +35,6 @@ var addAssignOpType = &operationType{Type: "ADD_ASSIGN", NumArgs: 2, Precedence:
 
 var assignAttributesOpType = &operationType{Type: "ASSIGN_ATTRIBUTES", NumArgs: 2, Precedence: 40, Handler: assignAttributesOperator}
 var assignStyleOpType = &operationType{Type: "ASSIGN_STYLE", NumArgs: 2, Precedence: 40, Handler: assignStyleOperator}
-var assignVariableOpType = &operationType{Type: "ASSIGN_VARIABLE", NumArgs: 2, Precedence: 40, Handler: assignVariableOperator}
 var assignTagOpType = &operationType{Type: "ASSIGN_TAG", NumArgs: 2, Precedence: 40, Handler: assignTagOperator}
 var assignCommentOpType = &operationType{Type: "ASSIGN_COMMENT", NumArgs: 2, Precedence: 40, Handler: assignCommentsOperator}
 var assignAnchorOpType = &operationType{Type: "ASSIGN_ANCHOR", NumArgs: 2, Precedence: 40, Handler: assignAnchorOperator}
@@ -49,7 +45,6 @@ var addOpType = &operationType{Type: "ADD", NumArgs: 2, Precedence: 42, Handler:
 var alternativeOpType = &operationType{Type: "ALTERNATIVE", NumArgs: 2, Precedence: 42, Handler: alternativeOperator}
 
 var equalsOpType = &operationType{Type: "EQUALS", NumArgs: 2, Precedence: 40, Handler: equalsOperator}
-var notEqualsOpType = &operationType{Type: "EQUALS", NumArgs: 2, Precedence: 40, Handler: notEqualsOperator}
 var createMapOpType = &operationType{Type: "CREATE_MAP", NumArgs: 2, Precedence: 40, Handler: createMapOperator}
 
 var shortPipeOpType = &operationType{Type: "SHORT_PIPE", NumArgs: 2, Precedence: 45, Handler: pipeOperator}
@@ -57,7 +52,6 @@ var shortPipeOpType = &operationType{Type: "SHORT_PIPE", NumArgs: 2, Precedence:
 var lengthOpType = &operationType{Type: "LENGTH", NumArgs: 0, Precedence: 50, Handler: lengthOperator}
 var collectOpType = &operationType{Type: "COLLECT", NumArgs: 0, Precedence: 50, Handler: collectOperator}
 var splitDocumentOpType = &operationType{Type: "SPLIT_DOC", NumArgs: 0, Precedence: 50, Handler: splitDocumentOperator}
-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 getCommentOpType = &operationType{Type: "GET_COMMENT", NumArgs: 0, Precedence: 50, Handler: getCommentsOperator}
@@ -76,14 +70,14 @@ var splitStringOpType = &operationType{Type: "SPLIT", NumArgs: 1, Precedence: 50
 var keysOpType = &operationType{Type: "KEYS", NumArgs: 0, Precedence: 50, Handler: keysOperator}
 
 var collectObjectOpType = &operationType{Type: "COLLECT_OBJECT", NumArgs: 0, Precedence: 50, Handler: collectObjectOperator}
-var traversePathOpType = &operationType{Type: "TRAVERSE_PATH", NumArgs: 0, Precedence: 55, Handler: traversePathOperator}
+var traversePathOpType = &operationType{Type: "TRAVERSE_PATH", NumArgs: 0, Precedence: 50, Handler: traversePathOperator}
-var traverseArrayOpType = &operationType{Type: "TRAVERSE_ARRAY", NumArgs: 2, Precedence: 50, Handler: traverseArrayOperator}
+var traverseArrayOpType = &operationType{Type: "TRAVERSE_ARRAY", NumArgs: 1, Precedence: 50, Handler: traverseArrayOperator}
 
-var selfReferenceOpType = &operationType{Type: "SELF", NumArgs: 0, Precedence: 55, Handler: selfOperator}
+var selfReferenceOpType = &operationType{Type: "SELF", NumArgs: 0, Precedence: 50, Handler: selfOperator}
 var valueOpType = &operationType{Type: "VALUE", NumArgs: 0, Precedence: 50, Handler: valueOperator}
 var envOpType = &operationType{Type: "ENV", NumArgs: 0, Precedence: 50, Handler: envOperator}
 var notOpType = &operationType{Type: "NOT", NumArgs: 0, Precedence: 50, Handler: notOperator}
-var emptyOpType = &operationType{Type: "EMPTY", Precedence: 50, Handler: emptyOperator}
+var emptyOpType = &operationType{Type: "EMPTY", NumArgs: 50, Handler: emptyOperator}
 
 var recursiveDescentOpType = &operationType{Type: "RECURSIVE_DESCENT", NumArgs: 0, Precedence: 50, Handler: recursiveDescentOperator}
 

pkg/yqlib/operator_add.go

@@ -3,6 +3,7 @@ package yqlib
 import (
 	"fmt"
 
+	"container/list"
 	"strconv"
 
 	yaml "gopkg.in/yaml.v3"
@@ -14,12 +15,12 @@ func createAddOp(lhs *ExpressionNode, rhs *ExpressionNode) *ExpressionNode {
 		Rhs: rhs}
 }
 
-func addAssignOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func addAssignOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	assignmentOp := &Operation{OperationType: assignOpType}
 	assignmentOp.UpdateAssign = false
 
 	assignmentOpNode := &ExpressionNode{Operation: assignmentOp, Lhs: expressionNode.Lhs, Rhs: createAddOp(expressionNode.Lhs, expressionNode.Rhs)}
-	return d.GetMatchingNodes(context, assignmentOpNode)
+	return d.GetMatchingNodes(matchingNodes, assignmentOpNode)
 }
 
 func toNodes(candidate *CandidateNode) []*yaml.Node {
@@ -36,23 +37,18 @@ func toNodes(candidate *CandidateNode) []*yaml.Node {
 
 }
 
-func addOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func addOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("Add operator")
 
-	return crossFunction(d, context, expressionNode, add)
+	return crossFunction(d, matchingNodes, expressionNode, add)
 }
 
-func add(d *dataTreeNavigator, context Context, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
+func add(d *dataTreeNavigator, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
 	lhs.Node = unwrapDoc(lhs.Node)
 	rhs.Node = unwrapDoc(rhs.Node)
 
-	lhsNode := lhs.Node
-
-	if lhsNode.Tag == "!!null" {
-		return lhs.CreateChild(nil, rhs.Node), nil
-	}
-
 	target := lhs.CreateChild(nil, &yaml.Node{})
+	lhsNode := lhs.Node
 
 	switch lhsNode.Kind {
 	case yaml.MappingNode:

pkg/yqlib/operator_add_test.go

@@ -5,15 +5,6 @@ import (
 )
 
 var addOperatorScenarios = []expressionScenario{
-	{
-		skipDoc:    true,
-		document:   `[{a: foo, b: bar}, {a: 1, b: 2}]`,
-		expression: ".[] | .a + .b",
-		expected: []string{
-			"D0, P[0 a], (!!str)::foobar\n",
-			"D0, P[1 a], (!!int)::3\n",
-		},
-	},
 	{
 		description: "Concatenate and assign arrays",
 		document:    `{a: {val: thing, b: [cat,dog]}}`,
@@ -112,14 +103,6 @@ var addOperatorScenarios = []expressionScenario{
 			"D0, P[], (doc)::{a: 4}\n",
 		},
 	},
-	{
-		description:    "Add to null",
-		subdescription: "Adding to null simply returns the rhs",
-		expression:     `null + "cat"`,
-		expected: []string{
-			"D0, P[], (!!str)::cat\n",
-		},
-	},
 }
 
 func TestAddOperatorScenarios(t *testing.T) {

pkg/yqlib/operator_alternative.go

@@ -1,14 +1,18 @@
 package yqlib
 
+import (
+	"container/list"
+)
+
 // corssFunction no matches
 // can boolean use crossfunction
 
-func alternativeOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func alternativeOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("-- alternative")
-	return crossFunction(d, context, expressionNode, alternativeFunc)
+	return crossFunction(d, matchingNodes, expressionNode, alternativeFunc)
 }
 
-func alternativeFunc(d *dataTreeNavigator, context Context, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
+func alternativeFunc(d *dataTreeNavigator, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
 	lhs.Node = unwrapDoc(lhs.Node)
 	rhs.Node = unwrapDoc(rhs.Node)
 	log.Debugf("Alternative LHS: %v", lhs.Node.Tag)

pkg/yqlib/operator_anchors_aliases.go

@@ -6,146 +6,146 @@ import (
 	yaml "gopkg.in/yaml.v3"
 )
 
-func assignAliasOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func assignAliasOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 
 	log.Debugf("AssignAlias operator!")
 
 	aliasName := ""
 	if !expressionNode.Operation.UpdateAssign {
-		rhs, err := d.GetMatchingNodes(context, expressionNode.Rhs)
+		rhs, err := d.GetMatchingNodes(matchingNodes, expressionNode.Rhs)
 		if err != nil {
-			return Context{}, err
+			return nil, err
 		}
-		if rhs.MatchingNodes.Front() != nil {
+		if rhs.Front() != nil {
-			aliasName = rhs.MatchingNodes.Front().Value.(*CandidateNode).Node.Value
+			aliasName = rhs.Front().Value.(*CandidateNode).Node.Value
 		}
 	}
 
-	lhs, err := d.GetMatchingNodes(context, expressionNode.Lhs)
+	lhs, err := d.GetMatchingNodes(matchingNodes, expressionNode.Lhs)
 
 	if err != nil {
-		return Context{}, err
+		return nil, err
 	}
 
-	for el := lhs.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := lhs.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		log.Debugf("Setting aliasName : %v", candidate.GetKey())
 
 		if expressionNode.Operation.UpdateAssign {
-			rhs, err := d.GetMatchingNodes(context.SingleChildContext(candidate), expressionNode.Rhs)
+			rhs, err := d.GetMatchingNodes(nodeToMap(candidate), expressionNode.Rhs)
 			if err != nil {
-				return Context{}, err
+				return nil, err
 			}
-			if rhs.MatchingNodes.Front() != nil {
+			if rhs.Front() != nil {
-				aliasName = rhs.MatchingNodes.Front().Value.(*CandidateNode).Node.Value
+				aliasName = rhs.Front().Value.(*CandidateNode).Node.Value
 			}
 		}
 
 		candidate.Node.Kind = yaml.AliasNode
 		candidate.Node.Value = aliasName
 	}
-	return context, nil
+	return matchingNodes, nil
 }
 
-func getAliasOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func getAliasOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("GetAlias operator!")
 	var results = list.New()
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := 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)
 		results.PushBack(result)
 	}
-	return context.ChildContext(results), nil
+	return results, nil
 }
 
-func assignAnchorOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func assignAnchorOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 
 	log.Debugf("AssignAnchor operator!")
 
 	anchorName := ""
 	if !expressionNode.Operation.UpdateAssign {
-		rhs, err := d.GetMatchingNodes(context, expressionNode.Rhs)
+		rhs, err := d.GetMatchingNodes(matchingNodes, expressionNode.Rhs)
 		if err != nil {
-			return Context{}, err
+			return nil, err
 		}
 
-		if rhs.MatchingNodes.Front() != nil {
+		if rhs.Front() != nil {
-			anchorName = rhs.MatchingNodes.Front().Value.(*CandidateNode).Node.Value
+			anchorName = rhs.Front().Value.(*CandidateNode).Node.Value
 		}
 	}
 
-	lhs, err := d.GetMatchingNodes(context, expressionNode.Lhs)
+	lhs, err := d.GetMatchingNodes(matchingNodes, expressionNode.Lhs)
 
 	if err != nil {
-		return Context{}, err
+		return nil, err
 	}
 
-	for el := lhs.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := lhs.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		log.Debugf("Setting anchorName of : %v", candidate.GetKey())
 
 		if expressionNode.Operation.UpdateAssign {
-			rhs, err := d.GetMatchingNodes(context.SingleChildContext(candidate), expressionNode.Rhs)
+			rhs, err := d.GetMatchingNodes(nodeToMap(candidate), expressionNode.Rhs)
 			if err != nil {
-				return Context{}, err
+				return nil, err
 			}
 
-			if rhs.MatchingNodes.Front() != nil {
+			if rhs.Front() != nil {
-				anchorName = rhs.MatchingNodes.Front().Value.(*CandidateNode).Node.Value
+				anchorName = rhs.Front().Value.(*CandidateNode).Node.Value
 			}
 		}
 
 		candidate.Node.Anchor = anchorName
 	}
-	return context, nil
+	return matchingNodes, nil
 }
 
-func getAnchorOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func getAnchorOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("GetAnchor operator!")
 	var results = list.New()
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := matchingNodes.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		anchor := candidate.Node.Anchor
 		node := &yaml.Node{Kind: yaml.ScalarNode, Value: anchor, Tag: "!!str"}
 		result := candidate.CreateChild(nil, node)
 		results.PushBack(result)
 	}
-	return context.ChildContext(results), nil
+	return results, nil
 }
 
-func explodeOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func explodeOperator(d *dataTreeNavigator, matchMap *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("-- ExplodeOperation")
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := matchMap.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 
-		rhs, err := d.GetMatchingNodes(context.SingleChildContext(candidate), expressionNode.Rhs)
+		rhs, err := d.GetMatchingNodes(nodeToMap(candidate), expressionNode.Rhs)
 
 		if err != nil {
-			return Context{}, err
+			return nil, err
 		}
-		for childEl := rhs.MatchingNodes.Front(); childEl != nil; childEl = childEl.Next() {
+		for childEl := rhs.Front(); childEl != nil; childEl = childEl.Next() {
-			err = explodeNode(childEl.Value.(*CandidateNode).Node, context)
+			err = explodeNode(childEl.Value.(*CandidateNode).Node)
 			if err != nil {
-				return Context{}, err
+				return nil, err
 			}
 		}
 
 	}
 
-	return context, nil
+	return matchMap, nil
 }
 
-func explodeNode(node *yaml.Node, context Context) error {
+func explodeNode(node *yaml.Node) error {
 	node.Anchor = ""
 	switch node.Kind {
 	case yaml.SequenceNode, yaml.DocumentNode:
 		for index, contentNode := range node.Content {
 			log.Debugf("exploding index %v", index)
-			errorInContent := explodeNode(contentNode, context)
+			errorInContent := explodeNode(contentNode)
 			if errorInContent != nil {
 				return errorInContent
 			}
@@ -169,7 +169,7 @@ func explodeNode(node *yaml.Node, context Context) error {
 			valueNode := node.Content[index+1]
 			log.Debugf("traversing %v", keyNode.Value)
 			if keyNode.Value != "<<" {
-				err := overrideEntry(node, keyNode, valueNode, index, context.ChildContext(newContent))
+				err := overrideEntry(node, keyNode, valueNode, index, newContent)
 				if err != nil {
 					return err
 				}
@@ -178,14 +178,14 @@ func explodeNode(node *yaml.Node, context Context) error {
 					log.Debugf("an alias merge list!")
 					for index := 0; index < len(valueNode.Content); index = index + 1 {
 						aliasNode := valueNode.Content[index]
-						err := applyAlias(node, aliasNode.Alias, index, context.ChildContext(newContent))
+						err := applyAlias(node, aliasNode.Alias, index, newContent)
 						if err != nil {
 							return err
 						}
 					}
 				} else {
 					log.Debugf("an alias merge!")
-					err := applyAlias(node, valueNode.Alias, index, context.ChildContext(newContent))
+					err := applyAlias(node, valueNode.Alias, index, newContent)
 					if err != nil {
 						return err
 					}
@@ -205,7 +205,7 @@ func explodeNode(node *yaml.Node, context Context) error {
 	}
 }
 
-func applyAlias(node *yaml.Node, alias *yaml.Node, aliasIndex int, newContent Context) error {
+func applyAlias(node *yaml.Node, alias *yaml.Node, aliasIndex int, newContent *list.List) error {
 	if alias == nil {
 		return nil
 	}
@@ -221,15 +221,15 @@ func applyAlias(node *yaml.Node, alias *yaml.Node, aliasIndex int, newContent Co
 	return nil
 }
 
-func overrideEntry(node *yaml.Node, key *yaml.Node, value *yaml.Node, startIndex int, newContent Context) error {
+func overrideEntry(node *yaml.Node, key *yaml.Node, value *yaml.Node, startIndex int, newContent *list.List) error {
 
-	err := explodeNode(value, newContent)
+	err := explodeNode(value)
 
 	if err != nil {
 		return err
 	}
 
-	for newEl := newContent.MatchingNodes.Front(); newEl != nil; newEl = newEl.Next() {
+	for newEl := newContent.Front(); newEl != nil; newEl = newEl.Next() {
 		valueEl := newEl.Next() // move forward twice
 		keyNode := newEl.Value.(*yaml.Node)
 		log.Debugf("checking new content %v:%v", keyNode.Value, valueEl.Value.(*yaml.Node).Value)
@@ -250,12 +250,12 @@ func overrideEntry(node *yaml.Node, key *yaml.Node, value *yaml.Node, startIndex
 		}
 	}
 
-	err = explodeNode(key, newContent)
+	err = explodeNode(key)
 	if err != nil {
 		return err
 	}
 	log.Debugf("adding %v:%v", key.Value, value.Value)
-	newContent.MatchingNodes.PushBack(key)
+	newContent.PushBack(key)
-	newContent.MatchingNodes.PushBack(value)
+	newContent.PushBack(value)
 	return nil
 }

pkg/yqlib/operator_assign.go

@@ -1,28 +1,30 @@
 package yqlib
 
-func assignUpdateOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+import "container/list"
-	lhs, err := d.GetMatchingNodes(context, expressionNode.Lhs)
+
+func assignUpdateOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
+	lhs, err := d.GetMatchingNodes(matchingNodes, expressionNode.Lhs)
 	if err != nil {
-		return Context{}, err
+		return nil, err
 	}
-	var rhs Context
+	var rhs *list.List
 	if !expressionNode.Operation.UpdateAssign {
-		rhs, err = d.GetMatchingNodes(context, expressionNode.Rhs)
+		rhs, err = d.GetMatchingNodes(matchingNodes, expressionNode.Rhs)
 	}
 
-	for el := lhs.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := lhs.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 
 		if expressionNode.Operation.UpdateAssign {
-			rhs, err = d.GetMatchingNodes(context.SingleChildContext(candidate), expressionNode.Rhs)
+			rhs, err = d.GetMatchingNodes(nodeToMap(candidate), expressionNode.Rhs)
 		}
 
 		if err != nil {
-			return Context{}, err
+			return nil, err
 		}
 
 		// grab the first value
-		first := rhs.MatchingNodes.Front()
+		first := rhs.Front()
 
 		if first != nil {
 			rhsCandidate := first.Value.(*CandidateNode)
@@ -31,31 +33,30 @@ func assignUpdateOperator(d *dataTreeNavigator, context Context, expressionNode
 		}
 	}
 
-	return context, nil
+	return matchingNodes, nil
 }
 
 // does not update content or values
-func assignAttributesOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func assignAttributesOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
-	log.Debug("getting lhs matching nodes for update")
+	lhs, err := d.GetMatchingNodes(matchingNodes, expressionNode.Lhs)
-	lhs, err := d.GetMatchingNodes(context, expressionNode.Lhs)
 	if err != nil {
-		return Context{}, err
+		return nil, err
 	}
-	for el := lhs.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := lhs.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 
-		rhs, err := d.GetMatchingNodes(context.SingleChildContext(candidate), expressionNode.Rhs)
+		rhs, err := d.GetMatchingNodes(nodeToMap(candidate), expressionNode.Rhs)
 
 		if err != nil {
-			return Context{}, err
+			return nil, err
 		}
 
 		// grab the first value
-		first := rhs.MatchingNodes.Front()
+		first := rhs.Front()
 
 		if first != nil {
 			candidate.UpdateAttributesFrom(first.Value.(*CandidateNode))
 		}
 	}
-	return context, nil
+	return matchingNodes, nil
 }

pkg/yqlib/operator_booleans.go

@@ -25,8 +25,8 @@ func isTruthy(c *CandidateNode) (bool, error) {
 
 type boolOp func(bool, bool) bool
 
-func performBoolOp(op boolOp) func(d *dataTreeNavigator, context Context, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
+func performBoolOp(op boolOp) func(d *dataTreeNavigator, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
-	return func(d *dataTreeNavigator, context Context, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
+	return func(d *dataTreeNavigator, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
 		lhs.Node = unwrapDoc(lhs.Node)
 		rhs.Node = unwrapDoc(rhs.Node)
 
@@ -44,35 +44,35 @@ func performBoolOp(op boolOp) func(d *dataTreeNavigator, context Context, lhs *C
 	}
 }
 
-func orOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func orOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("-- orOp")
-	return crossFunction(d, context, expressionNode, performBoolOp(
+	return crossFunction(d, matchingNodes, expressionNode, performBoolOp(
 		func(b1 bool, b2 bool) bool {
 			return b1 || b2
 		}))
 }
 
-func andOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func andOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("-- AndOp")
-	return crossFunction(d, context, expressionNode, performBoolOp(
+	return crossFunction(d, matchingNodes, expressionNode, performBoolOp(
 		func(b1 bool, b2 bool) bool {
 			return b1 && b2
 		}))
 }
 
-func notOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func notOperator(d *dataTreeNavigator, matchMap *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("-- notOperation")
 	var results = list.New()
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := matchMap.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		log.Debug("notOperation checking %v", candidate)
 		truthy, errDecoding := isTruthy(candidate)
 		if errDecoding != nil {
-			return Context{}, errDecoding
+			return nil, errDecoding
 		}
 		result := createBooleanCandidate(candidate, !truthy)
 		results.PushBack(result)
 	}
-	return context.ChildContext(results), nil
+	return results, nil
 }

pkg/yqlib/operator_collect.go

@@ -6,21 +6,21 @@ import (
 	yaml "gopkg.in/yaml.v3"
 )
 
-func collectOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func collectOperator(d *dataTreeNavigator, matchMap *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("-- collectOperation")
 
-	if context.MatchingNodes.Len() == 0 {
+	if matchMap.Len() == 0 {
 		node := &yaml.Node{Kind: yaml.SequenceNode, Tag: "!!seq", Value: "[]"}
 		candidate := &CandidateNode{Node: node}
-		return context.SingleChildContext(candidate), nil
+		return nodeToMap(candidate), nil
 	}
 
 	var results = list.New()
 
 	node := &yaml.Node{Kind: yaml.SequenceNode, Tag: "!!seq"}
 	var collectC *CandidateNode
-	if context.MatchingNodes.Front() != nil {
+	if matchMap.Front() != nil {
-		collectC = context.MatchingNodes.Front().Value.(*CandidateNode).CreateChild(nil, node)
+		collectC = matchMap.Front().Value.(*CandidateNode).CreateChild(nil, node)
 		if len(collectC.Path) > 0 {
 			collectC.Path = collectC.Path[:len(collectC.Path)-1]
 		}
@@ -28,7 +28,7 @@ func collectOperator(d *dataTreeNavigator, context Context, expressionNode *Expr
 		collectC = &CandidateNode{Node: node}
 	}
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := matchMap.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		log.Debugf("Collecting %v", NodeToString(candidate))
 		node.Content = append(node.Content, unwrapDoc(candidate.Node))
@@ -36,5 +36,5 @@ func collectOperator(d *dataTreeNavigator, context Context, expressionNode *Expr
 
 	results.PushBack(collectC)
 
-	return context.ChildContext(results), nil
+	return results, nil
 }

pkg/yqlib/operator_collect_object.go

@@ -17,22 +17,22 @@ import (
 ...
 */
 
-func collectObjectOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func collectObjectOperator(d *dataTreeNavigator, matchMap *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("-- collectObjectOperation")
 
-	if context.MatchingNodes.Len() == 0 {
+	if matchMap.Len() == 0 {
 		node := &yaml.Node{Kind: yaml.MappingNode, Tag: "!!map", Value: "{}"}
 		candidate := &CandidateNode{Node: node}
-		return context.SingleChildContext(candidate), nil
+		return nodeToMap(candidate), nil
 	}
-	first := context.MatchingNodes.Front().Value.(*CandidateNode)
+	first := matchMap.Front().Value.(*CandidateNode)
 	var rotated []*list.List = make([]*list.List, len(first.Node.Content))
 
 	for i := 0; i < len(first.Node.Content); i++ {
 		rotated[i] = list.New()
 	}
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := matchMap.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]))
@@ -41,59 +41,59 @@ func collectObjectOperator(d *dataTreeNavigator, context Context, expressionNode
 
 	newObject := list.New()
 	for i := 0; i < len(first.Node.Content); i++ {
-		additions, err := collect(d, context.ChildContext(list.New()), rotated[i])
+		additions, err := collect(d, list.New(), rotated[i])
 		if err != nil {
-			return Context{}, err
+			return nil, err
 		}
-		newObject.PushBackList(additions.MatchingNodes)
+		newObject.PushBackList(additions)
 	}
 
-	return context.ChildContext(newObject), nil
+	return newObject, nil
 
 }
 
-func collect(d *dataTreeNavigator, context Context, remainingMatches *list.List) (Context, error) {
+func collect(d *dataTreeNavigator, aggregate *list.List, remainingMatches *list.List) (*list.List, error) {
 	if remainingMatches.Len() == 0 {
-		return context, nil
+		return aggregate, nil
 	}
 
 	candidate := remainingMatches.Remove(remainingMatches.Front()).(*CandidateNode)
 
-	splatted, err := splat(d, context.SingleChildContext(candidate),
+	splatted, err := splat(d, nodeToMap(candidate),
 		traversePreferences{DontFollowAlias: true, IncludeMapKeys: false})
 
-	for splatEl := splatted.MatchingNodes.Front(); splatEl != nil; splatEl = splatEl.Next() {
+	for splatEl := splatted.Front(); splatEl != nil; splatEl = splatEl.Next() {
 		splatEl.Value.(*CandidateNode).Path = nil
 	}
 
 	if err != nil {
-		return Context{}, err
+		return nil, err
 	}
 
-	if context.MatchingNodes.Len() == 0 {
+	if aggregate.Len() == 0 {
 		return collect(d, splatted, remainingMatches)
 	}
 
 	newAgg := list.New()
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := aggregate.Front(); el != nil; el = el.Next() {
 		aggCandidate := el.Value.(*CandidateNode)
-		for splatEl := splatted.MatchingNodes.Front(); splatEl != nil; splatEl = splatEl.Next() {
+		for splatEl := splatted.Front(); splatEl != nil; splatEl = splatEl.Next() {
 			splatCandidate := splatEl.Value.(*CandidateNode)
 			newCandidate, err := aggCandidate.Copy()
 			if err != nil {
-				return Context{}, err
+				return nil, err
 			}
 
 			newCandidate.Path = nil
 
-			newCandidate, err = multiply(multiplyPreferences{AppendArrays: false})(d, context, newCandidate, splatCandidate)
+			newCandidate, err = multiply(multiplyPreferences{AppendArrays: false})(d, newCandidate, splatCandidate)
 			if err != nil {
-				return Context{}, err
+				return nil, err
 			}
 			newAgg.PushBack(newCandidate)
 		}
 	}
-	return collect(d, context.ChildContext(newAgg), remainingMatches)
+	return collect(d, newAgg, remainingMatches)
 
 }

pkg/yqlib/operator_comments.go

@@ -13,41 +13,41 @@ type commentOpPreferences struct {
 	FootComment bool
 }
 
-func assignCommentsOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func assignCommentsOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 
 	log.Debugf("AssignComments operator!")
 
-	lhs, err := d.GetMatchingNodes(context, expressionNode.Lhs)
+	lhs, err := d.GetMatchingNodes(matchingNodes, expressionNode.Lhs)
 
 	if err != nil {
-		return Context{}, err
+		return nil, err
 	}
 
 	preferences := expressionNode.Operation.Preferences.(commentOpPreferences)
 
 	comment := ""
 	if !expressionNode.Operation.UpdateAssign {
-		rhs, err := d.GetMatchingNodes(context, expressionNode.Rhs)
+		rhs, err := d.GetMatchingNodes(matchingNodes, expressionNode.Rhs)
 		if err != nil {
-			return Context{}, err
+			return nil, err
 		}
 
-		if rhs.MatchingNodes.Front() != nil {
+		if rhs.Front() != nil {
-			comment = rhs.MatchingNodes.Front().Value.(*CandidateNode).Node.Value
+			comment = rhs.Front().Value.(*CandidateNode).Node.Value
 		}
 	}
 
-	for el := lhs.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := lhs.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 
 		if expressionNode.Operation.UpdateAssign {
-			rhs, err := d.GetMatchingNodes(context.SingleChildContext(candidate), expressionNode.Rhs)
+			rhs, err := d.GetMatchingNodes(nodeToMap(candidate), expressionNode.Rhs)
 			if err != nil {
-				return Context{}, err
+				return nil, err
 			}
 
-			if rhs.MatchingNodes.Front() != nil {
+			if rhs.Front() != nil {
-				comment = rhs.MatchingNodes.Front().Value.(*CandidateNode).Node.Value
+				comment = rhs.Front().Value.(*CandidateNode).Node.Value
 			}
 		}
 
@@ -63,15 +63,15 @@ func assignCommentsOperator(d *dataTreeNavigator, context Context, expressionNod
 		}
 
 	}
-	return context, nil
+	return matchingNodes, nil
 }
 
-func getCommentsOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func getCommentsOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	preferences := expressionNode.Operation.Preferences.(commentOpPreferences)
 	log.Debugf("GetComments operator!")
 	var results = list.New()
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := matchingNodes.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		comment := ""
 		if preferences.LineComment {
@@ -87,5 +87,5 @@ func getCommentsOperator(d *dataTreeNavigator, context Context, expressionNode *
 		result := candidate.CreateChild(nil, node)
 		results.PushBack(result)
 	}
-	return context.ChildContext(results), nil
+	return results, nil
 }

pkg/yqlib/operator_create_map.go

@@ -6,7 +6,7 @@ import (
 	"gopkg.in/yaml.v3"
 )
 
-func createMapOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func createMapOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("-- createMapOperation")
 
 	//each matchingNodes entry should turn into a sequence of keys to create.
@@ -18,29 +18,29 @@ func createMapOperator(d *dataTreeNavigator, context Context, expressionNode *Ex
 
 	sequences := list.New()
 
-	if context.MatchingNodes.Len() > 0 {
+	if matchingNodes.Len() > 0 {
 
-		for matchingNodeEl := context.MatchingNodes.Front(); matchingNodeEl != nil; matchingNodeEl = matchingNodeEl.Next() {
+		for matchingNodeEl := matchingNodes.Front(); matchingNodeEl != nil; matchingNodeEl = matchingNodeEl.Next() {
 			matchingNode := matchingNodeEl.Value.(*CandidateNode)
-			sequenceNode, err := sequenceFor(d, context, matchingNode, expressionNode)
+			sequenceNode, err := sequenceFor(d, matchingNode, expressionNode)
 			if err != nil {
-				return Context{}, err
+				return nil, err
 			}
 			sequences.PushBack(sequenceNode)
 		}
 	} else {
-		sequenceNode, err := sequenceFor(d, context, nil, expressionNode)
+		sequenceNode, err := sequenceFor(d, nil, expressionNode)
 		if err != nil {
-			return Context{}, err
+			return nil, err
 		}
 		sequences.PushBack(sequenceNode)
 	}
 
-	return context.SingleChildContext(&CandidateNode{Node: listToNodeSeq(sequences), Document: document, Path: path}), nil
+	return nodeToMap(&CandidateNode{Node: listToNodeSeq(sequences), Document: document, Path: path}), nil
 
 }
 
-func sequenceFor(d *dataTreeNavigator, context Context, matchingNode *CandidateNode, expressionNode *ExpressionNode) (*CandidateNode, error) {
+func sequenceFor(d *dataTreeNavigator, matchingNode *CandidateNode, expressionNode *ExpressionNode) (*CandidateNode, error) {
 	var path []interface{}
 	var document uint = 0
 	var matches = list.New()
@@ -48,11 +48,11 @@ func sequenceFor(d *dataTreeNavigator, context Context, matchingNode *CandidateN
 	if matchingNode != nil {
 		path = matchingNode.Path
 		document = matchingNode.Document
-		matches.PushBack(matchingNode)
+		matches = nodeToMap(matchingNode)
 	}
 
-	mapPairs, err := crossFunction(d, context.ChildContext(matches), expressionNode,
+	mapPairs, err := crossFunction(d, matches, expressionNode,
-		func(d *dataTreeNavigator, context Context, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
+		func(d *dataTreeNavigator, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
 			node := yaml.Node{Kind: yaml.MappingNode, Tag: "!!map"}
 			log.Debugf("LHS:", NodeToString(lhs))
 			log.Debugf("RHS:", NodeToString(rhs))
@@ -67,7 +67,7 @@ func sequenceFor(d *dataTreeNavigator, context Context, matchingNode *CandidateN
 	if err != nil {
 		return nil, err
 	}
-	innerList := listToNodeSeq(mapPairs.MatchingNodes)
+	innerList := listToNodeSeq(mapPairs)
 	innerList.Style = yaml.FlowStyle
 	return &CandidateNode{Node: innerList, Document: document, Path: path}, nil
 }

pkg/yqlib/operator_delete.go

@@ -1,24 +1,23 @@
 package yqlib
 
 import (
+	"container/list"
 	"fmt"
 
 	yaml "gopkg.in/yaml.v3"
 )
 
-func deleteChildOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func deleteChildOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
-	contextToUse := context.Clone()
+
-	contextToUse.DontAutoCreate = true
+	nodesToDelete, err := d.GetMatchingNodes(matchingNodes, expressionNode.Rhs)
-	nodesToDelete, err := d.GetMatchingNodes(contextToUse, expressionNode.Rhs)
 
 	if err != nil {
-		return Context{}, err
+		return nil, err
 	}
-	//need to iterate backwards to ensure correct indices when deleting multiple
+
-	for el := nodesToDelete.MatchingNodes.Back(); el != nil; el = el.Prev() {
+	for el := nodesToDelete.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 
-		if len(candidate.Path) > 0 {
 		deleteImmediateChildOp := &Operation{
 			OperationType: deleteImmediateChildOpType,
 			Value:         candidate.Path[len(candidate.Path)-1],
@@ -26,30 +25,29 @@ func deleteChildOperator(d *dataTreeNavigator, context Context, expressionNode *
 
 		deleteImmediateChildOpNode := &ExpressionNode{
 			Operation: deleteImmediateChildOp,
-				Rhs:       createTraversalTree(candidate.Path[0:len(candidate.Path)-1], traversePreferences{}, false),
+			Rhs:       createTraversalTree(candidate.Path[0:len(candidate.Path)-1], traversePreferences{}),
 		}
 
-			_, err := d.GetMatchingNodes(contextToUse, deleteImmediateChildOpNode)
+		_, err := d.GetMatchingNodes(matchingNodes, deleteImmediateChildOpNode)
 		if err != nil {
-				return Context{}, err
+			return nil, err
 		}
 	}
-	}
+	return matchingNodes, nil
-	return context, nil
 }
 
-func deleteImmediateChildOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func deleteImmediateChildOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
-	parents, err := d.GetMatchingNodes(context, expressionNode.Rhs)
+	parents, err := d.GetMatchingNodes(matchingNodes, expressionNode.Rhs)
 
 	if err != nil {
-		return Context{}, err
+		return nil, err
 	}
 
 	childPath := expressionNode.Operation.Value
 
 	log.Debug("childPath to remove %v", childPath)
 
-	for el := parents.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := parents.Front(); el != nil; el = el.Next() {
 		parent := el.Value.(*CandidateNode)
 		parentNode := unwrapDoc(parent.Node)
 		if parentNode.Kind == yaml.MappingNode {
@@ -57,11 +55,11 @@ func deleteImmediateChildOperator(d *dataTreeNavigator, context Context, express
 		} else if parentNode.Kind == yaml.SequenceNode {
 			deleteFromArray(parent, childPath)
 		} else {
-			return Context{}, fmt.Errorf("Cannot delete nodes from parent of tag %v", parentNode.Tag)
+			return nil, fmt.Errorf("Cannot delete nodes from parent of tag %v", parentNode.Tag)
 		}
 
 	}
-	return context, nil
+	return matchingNodes, nil
 }
 
 func deleteFromMap(candidate *CandidateNode, childPath interface{}) {

pkg/yqlib/operator_delete_test.go

@@ -37,38 +37,6 @@ var deleteOperatorScenarios = []expressionScenario{
 			"D0, P[], (doc)::[1, 3]\n",
 		},
 	},
-	{
-		skipDoc:    true,
-		document:   `a: [1,2,3]`,
-		expression: `del(.a[])`,
-		expected: []string{
-			"D0, P[], (doc)::a: []\n",
-		},
-	},
-	{
-		skipDoc:    true,
-		document:   `a: [10,x,10, 10, x, 10]`,
-		expression: `del(.a[] | select(. == 10))`,
-		expected: []string{
-			"D0, P[], (doc)::a: [x, x]\n",
-		},
-	},
-	{
-		skipDoc:    true,
-		document:   `a: {thing1: yep, thing2: cool, thing3: hi, b: {thing1: cool, great: huh}}`,
-		expression: `del(..)`,
-		expected: []string{
-			"D0, P[], (!!map)::{}\n",
-		},
-	},
-	{
-		skipDoc:    true,
-		document:   `a: {thing1: yep, thing2: cool, thing3: hi, b: {thing1: cool, great: huh}}`,
-		expression: `del(.. | select(tag == "!!map") | (.b.thing1,.thing2))`,
-		expected: []string{
-			"D0, P[], (!!map)::a: {thing1: yep, thing3: hi, b: {great: huh}}\n",
-		},
-	},
 	{
 		description: "Delete nested entry in array",
 		document:    `[{a: cat, b: dog}]`,

pkg/yqlib/operator_document_index.go

@@ -7,14 +7,14 @@ import (
 	"gopkg.in/yaml.v3"
 )
 
-func getDocumentIndexOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func getDocumentIndexOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	var results = list.New()
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := 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)
 		results.PushBack(scalar)
 	}
-	return context.ChildContext(results), nil
+	return results, nil
 }

pkg/yqlib/operator_env.go

@@ -1,6 +1,7 @@
 package yqlib
 
 import (
+	"container/list"
 	"fmt"
 	"os"
 	"strings"
@@ -12,7 +13,7 @@ type envOpPreferences struct {
 	StringValue bool
 }
 
-func envOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func envOperator(d *dataTreeNavigator, matchMap *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	envName := expressionNode.Operation.CandidateNode.Node.Value
 	log.Debug("EnvOperator, env name:", envName)
 
@@ -28,13 +29,13 @@ func envOperator(d *dataTreeNavigator, context Context, expressionNode *Expressi
 			Value: rawValue,
 		}
 	} else if rawValue == "" {
-		return Context{}, fmt.Errorf("Value for env variable '%v' not provided in env()", envName)
+		return nil, fmt.Errorf("Value for env variable '%v' not provided in env()", envName)
 	} else {
 		var dataBucket yaml.Node
 		decoder := yaml.NewDecoder(strings.NewReader(rawValue))
 		errorReading := decoder.Decode(&dataBucket)
 		if errorReading != nil {
-			return Context{}, errorReading
+			return nil, errorReading
 		}
 		//first node is a doc
 		node = unwrapDoc(&dataBucket)
@@ -45,5 +46,5 @@ func envOperator(d *dataTreeNavigator, context Context, expressionNode *Expressi
 
 	target := &CandidateNode{Node: node}
 
-	return context.SingleChildContext(target), nil
+	return nodeToMap(target), nil
 }

pkg/yqlib/operator_equals.go

@@ -1,14 +1,15 @@
 package yqlib
 
-import "gopkg.in/yaml.v3"
+import (
+	"container/list"
+)
 
-func equalsOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func equalsOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("-- equalsOperation")
-	return crossFunction(d, context, expressionNode, isEquals(false))
+	return crossFunction(d, matchingNodes, expressionNode, isEquals)
 }
 
-func isEquals(flip bool) func(d *dataTreeNavigator, context Context, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
+func isEquals(d *dataTreeNavigator, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
-	return func(d *dataTreeNavigator, context Context, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
 	value := false
 
 	lhsNode := unwrapDoc(lhs.Node)
@@ -16,18 +17,9 @@ func isEquals(flip bool) func(d *dataTreeNavigator, context Context, lhs *Candid
 
 	if lhsNode.Tag == "!!null" {
 		value = (rhsNode.Tag == "!!null")
-		} else if lhsNode.Kind == yaml.ScalarNode && rhsNode.Kind == yaml.ScalarNode {
+	} else {
 		value = matchKey(lhsNode.Value, rhsNode.Value)
 	}
 	log.Debugf("%v == %v ? %v", NodeToString(lhs), NodeToString(rhs), value)
-		if flip {
-			value = !value
-		}
 	return createBooleanCandidate(lhs, value), nil
 }
-}
-
-func notEqualsOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
-	log.Debugf("-- equalsOperation")
-	return crossFunction(d, context, expressionNode, isEquals(true))
-}

pkg/yqlib/operator_equals_test.go

@@ -14,14 +14,6 @@ var equalsOperatorScenarios = []expressionScenario{
 			"D0, P[], (!!bool)::false\n",
 		},
 	},
-	{
-		skipDoc:    true,
-		document:   "{a: { b: {things: \"\"}, f: [1], g: [] }}",
-		expression: ".. | select(. == \"\")",
-		expected: []string{
-			"D0, P[a b things], (!!str)::\"\"\n",
-		},
-	},
 	{
 		description: "Match string",
 		document:    `[cat,goat,dog]`,
@@ -31,18 +23,7 @@ var equalsOperatorScenarios = []expressionScenario{
 			"D0, P[1], (!!bool)::true\n",
 			"D0, P[2], (!!bool)::false\n",
 		},
-	},
+	}, {
-	{
-		description: "Don't match string",
-		document:    `[cat,goat,dog]`,
-		expression:  `.[] | (. != "*at")`,
-		expected: []string{
-			"D0, P[0], (!!bool)::false\n",
-			"D0, P[1], (!!bool)::false\n",
-			"D0, P[2], (!!bool)::true\n",
-		},
-	},
-	{
 		description: "Match number",
 		document:    `[3, 4, 5]`,
 		expression:  `.[] | (. == 4)`,
@@ -51,18 +32,7 @@ var equalsOperatorScenarios = []expressionScenario{
 			"D0, P[1], (!!bool)::true\n",
 			"D0, P[2], (!!bool)::false\n",
 		},
-	},
+	}, {
-	{
-		description: "Dont match number",
-		document:    `[3, 4, 5]`,
-		expression:  `.[] | (. != 4)`,
-		expected: []string{
-			"D0, P[0], (!!bool)::true\n",
-			"D0, P[1], (!!bool)::false\n",
-			"D0, P[2], (!!bool)::true\n",
-		},
-	},
-	{
 		skipDoc:    true,
 		document:   `a: { cat: {b: apple, c: whatever}, pat: {b: banana} }`,
 		expression: `.a | (.[].b == "apple")`,

pkg/yqlib/operator_file.go

@@ -7,32 +7,32 @@ import (
 	yaml "gopkg.in/yaml.v3"
 )
 
-func getFilenameOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func getFilenameOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("GetFilename")
 
 	var results = list.New()
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := 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)
 		results.PushBack(result)
 	}
 
-	return context.ChildContext(results), nil
+	return results, nil
 }
 
-func getFileIndexOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func getFileIndexOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("GetFileIndex")
 
 	var results = list.New()
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := 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)
 		results.PushBack(result)
 	}
 
-	return context.ChildContext(results), nil
+	return results, nil
 }

pkg/yqlib/operator_has.go

@@ -7,20 +7,20 @@ import (
 	yaml "gopkg.in/yaml.v3"
 )
 
-func hasOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func hasOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 
 	log.Debugf("-- hasOperation")
 	var results = list.New()
 
-	rhs, err := d.GetMatchingNodes(context, expressionNode.Rhs)
+	rhs, err := d.GetMatchingNodes(matchingNodes, expressionNode.Rhs)
-	wanted := rhs.MatchingNodes.Front().Value.(*CandidateNode).Node
+	wanted := rhs.Front().Value.(*CandidateNode).Node
 	wantedKey := wanted.Value
 
 	if err != nil {
-		return Context{}, err
+		return nil, err
 	}
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := matchingNodes.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 
 		// grab the first value
@@ -41,7 +41,7 @@ func hasOperator(d *dataTreeNavigator, context Context, expressionNode *Expressi
 			if wanted.Tag == "!!int" {
 				var number, errParsingInt = strconv.ParseInt(wantedKey, 10, 64) // nolint
 				if errParsingInt != nil {
-					return Context{}, errParsingInt
+					return nil, errParsingInt
 				}
 				candidateHasKey = int64(len(contents)) > number
 			}
@@ -50,5 +50,5 @@ func hasOperator(d *dataTreeNavigator, context Context, expressionNode *Expressi
 			results.PushBack(createBooleanCandidate(candidate, false))
 		}
 	}
-	return context.ChildContext(results), nil
+	return results, nil
 }

pkg/yqlib/operator_keys.go

@@ -7,12 +7,12 @@ import (
 	"gopkg.in/yaml.v3"
 )
 
-func keysOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func keysOperator(d *dataTreeNavigator, matchMap *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("-- keysOperator")
 
 	var results = list.New()
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := matchMap.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		node := unwrapDoc(candidate.Node)
 		var targetNode *yaml.Node
@@ -21,14 +21,14 @@ func keysOperator(d *dataTreeNavigator, context Context, expressionNode *Express
 		} else if node.Kind == yaml.SequenceNode {
 			targetNode = getIndicies(node)
 		} else {
-			return Context{}, fmt.Errorf("Cannot get keys of %v, keys only works for maps and arrays", node.Tag)
+			return nil, fmt.Errorf("Cannot get keys of %v, keys only works for maps and arrays", node.Tag)
 		}
 
 		result := candidate.CreateChild(nil, targetNode)
 		results.PushBack(result)
 	}
 
-	return context.ChildContext(results), nil
+	return results, nil
 }
 
 func getMapKeys(node *yaml.Node) *yaml.Node {

pkg/yqlib/operator_length.go

@@ -7,21 +7,17 @@ import (
 	yaml "gopkg.in/yaml.v3"
 )
 
-func lengthOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func lengthOperator(d *dataTreeNavigator, matchMap *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("-- lengthOperation")
 	var results = list.New()
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := matchMap.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		targetNode := unwrapDoc(candidate.Node)
 		var length int
 		switch targetNode.Kind {
 		case yaml.ScalarNode:
-			if targetNode.Tag == "!!null" {
-				length = 0
-			} else {
 			length = len(targetNode.Value)
-			}
 		case yaml.MappingNode:
 			length = len(targetNode.Content) / 2
 		case yaml.SequenceNode:
@@ -35,5 +31,5 @@ func lengthOperator(d *dataTreeNavigator, context Context, expressionNode *Expre
 		results.PushBack(result)
 	}
 
-	return context.ChildContext(results), nil
+	return results, nil
 }

pkg/yqlib/operator_length_test.go

@@ -14,30 +14,6 @@ var lengthOperatorScenarios = []expressionScenario{
 			"D0, P[a], (!!int)::3\n",
 		},
 	},
-	{
-		description: "null length",
-		document:    `{a: null}`,
-		expression:  `.a | length`,
-		expected: []string{
-			"D0, P[a], (!!int)::0\n",
-		},
-	},
-	{
-		skipDoc:    true,
-		document:   `{a: ~}`,
-		expression: `.a | length`,
-		expected: []string{
-			"D0, P[a], (!!int)::0\n",
-		},
-	},
-	{
-		skipDoc:    true,
-		document:   `{a: key no exist}`,
-		expression: `.b | length`,
-		expected: []string{
-			"D0, P[b], (!!int)::0\n",
-		},
-	},
 	{
 		description:    "Map length",
 		subdescription: "returns number of entries",

pkg/yqlib/operator_multiply.go

@@ -2,25 +2,59 @@ package yqlib
 
 import (
 	"fmt"
-	"strconv"
 
 	"container/list"
 
 	yaml "gopkg.in/yaml.v3"
 )
 
+type crossFunctionCalculation func(d *dataTreeNavigator, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error)
+
+func crossFunction(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode, calculation crossFunctionCalculation) (*list.List, error) {
+	lhs, err := d.GetMatchingNodes(matchingNodes, expressionNode.Lhs)
+	if err != nil {
+		return nil, err
+	}
+	log.Debugf("crossFunction LHS len: %v", lhs.Len())
+
+	rhs, err := d.GetMatchingNodes(matchingNodes, expressionNode.Rhs)
+
+	if err != nil {
+		return nil, err
+	}
+	log.Debugf("crossFunction RHS len: %v", rhs.Len())
+
+	var results = list.New()
+
+	for el := lhs.Front(); el != nil; el = el.Next() {
+		lhsCandidate := el.Value.(*CandidateNode)
+
+		for rightEl := rhs.Front(); rightEl != nil; rightEl = rightEl.Next() {
+			log.Debugf("Applying calc")
+			rhsCandidate := rightEl.Value.(*CandidateNode)
+			resultCandidate, err := calculation(d, lhsCandidate, rhsCandidate)
+			if err != nil {
+				return nil, err
+			}
+			results.PushBack(resultCandidate)
+		}
+
+	}
+	return results, nil
+}
+
 type multiplyPreferences struct {
 	AppendArrays  bool
 	TraversePrefs traversePreferences
 }
 
-func multiplyOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func multiplyOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("-- MultiplyOperator")
-	return crossFunction(d, context, expressionNode, multiply(expressionNode.Operation.Preferences.(multiplyPreferences)))
+	return crossFunction(d, matchingNodes, expressionNode, multiply(expressionNode.Operation.Preferences.(multiplyPreferences)))
 }
 
-func multiply(preferences multiplyPreferences) func(d *dataTreeNavigator, context Context, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
+func multiply(preferences multiplyPreferences) func(d *dataTreeNavigator, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
-	return func(d *dataTreeNavigator, context Context, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
+	return func(d *dataTreeNavigator, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
 		lhs.Node = unwrapDoc(lhs.Node)
 		rhs.Node = unwrapDoc(rhs.Node)
 		log.Debugf("Multipling LHS: %v", lhs.Node.Tag)
@@ -30,44 +64,25 @@ func multiply(preferences multiplyPreferences) func(d *dataTreeNavigator, contex
 			(lhs.Node.Kind == yaml.SequenceNode && rhs.Node.Kind == yaml.SequenceNode) {
 
 			var newBlank = lhs.CreateChild(nil, &yaml.Node{})
-			var newThing, err = mergeObjects(d, context, newBlank, lhs, multiplyPreferences{})
+			var newThing, err = mergeObjects(d, newBlank, lhs, multiplyPreferences{})
 			if err != nil {
 				return nil, err
 			}
-			return mergeObjects(d, context, newThing, rhs, preferences)
+			return mergeObjects(d, newThing, rhs, preferences)
-		} else if lhs.Node.Tag == "!!int" && rhs.Node.Tag == "!!int" {
+
-			return multiplyIntegers(lhs, rhs)
 		}
 		return nil, fmt.Errorf("Cannot multiply %v with %v", lhs.Node.Tag, rhs.Node.Tag)
 	}
 }
 
-func multiplyIntegers(lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
+func mergeObjects(d *dataTreeNavigator, lhs *CandidateNode, rhs *CandidateNode, preferences multiplyPreferences) (*CandidateNode, error) {
-	target := lhs.CreateChild(nil, &yaml.Node{})
-	target.Node.Kind = yaml.ScalarNode
-	target.Node.Style = lhs.Node.Style
-	target.Node.Tag = "!!int"
-
-	lhsNum, err := strconv.Atoi(lhs.Node.Value)
-	if err != nil {
-		return nil, err
-	}
-	rhsNum, err := strconv.Atoi(rhs.Node.Value)
-	if err != nil {
-		return nil, err
-	}
-	target.Node.Value = fmt.Sprintf("%v", lhsNum*rhsNum)
-	return target, nil
-}
-
-func mergeObjects(d *dataTreeNavigator, context Context, lhs *CandidateNode, rhs *CandidateNode, preferences multiplyPreferences) (*CandidateNode, error) {
 	shouldAppendArrays := preferences.AppendArrays
 	var results = list.New()
 
 	// shouldn't recurse arrays if appending
 	prefs := recursiveDescentPreferences{RecurseArray: !shouldAppendArrays,
-		TraversePreferences: traversePreferences{DontFollowAlias: true, IncludeMapKeys: true}}
+		TraversePreferences: traversePreferences{DontFollowAlias: true}}
-	err := recursiveDecent(d, results, context.SingleChildContext(rhs), prefs)
+	err := recursiveDecent(d, results, nodeToMap(rhs), prefs)
 	if err != nil {
 		return nil, err
 	}
@@ -78,12 +93,7 @@ func mergeObjects(d *dataTreeNavigator, context Context, lhs *CandidateNode, rhs
 	}
 
 	for el := results.Front(); el != nil; el = el.Next() {
-		candidate := el.Value.(*CandidateNode)
+		err := applyAssignment(d, pathIndexToStartFrom, lhs, el.Value.(*CandidateNode), preferences)
-		if candidate.Node.Tag == "!!merge" {
-			continue
-		}
-
-		err := applyAssignment(d, context, pathIndexToStartFrom, lhs, candidate, preferences)
 		if err != nil {
 			return nil, err
 		}
@@ -91,9 +101,9 @@ func mergeObjects(d *dataTreeNavigator, context Context, lhs *CandidateNode, rhs
 	return lhs, nil
 }
 
-func applyAssignment(d *dataTreeNavigator, context Context, pathIndexToStartFrom int, lhs *CandidateNode, rhs *CandidateNode, preferences multiplyPreferences) error {
+func applyAssignment(d *dataTreeNavigator, pathIndexToStartFrom int, lhs *CandidateNode, rhs *CandidateNode, preferences multiplyPreferences) error {
 	shouldAppendArrays := preferences.AppendArrays
-	log.Debugf("merge - applyAssignment lhs %v, rhs: %v", lhs.GetKey(), rhs.GetKey())
+	log.Debugf("merge - applyAssignment lhs %v, rhs: %v", NodeToString(lhs), NodeToString(rhs))
 
 	lhsPath := rhs.Path[pathIndexToStartFrom:]
 
@@ -106,9 +116,9 @@ func applyAssignment(d *dataTreeNavigator, context Context, pathIndexToStartFrom
 	}
 	rhsOp := &Operation{OperationType: valueOpType, CandidateNode: rhs}
 
-	assignmentOpNode := &ExpressionNode{Operation: assignmentOp, Lhs: createTraversalTree(lhsPath, preferences.TraversePrefs, rhs.IsMapKey), Rhs: &ExpressionNode{Operation: rhsOp}}
+	assignmentOpNode := &ExpressionNode{Operation: assignmentOp, Lhs: createTraversalTree(lhsPath, preferences.TraversePrefs), Rhs: &ExpressionNode{Operation: rhsOp}}
 
-	_, err := d.GetMatchingNodes(context.SingleChildContext(lhs), assignmentOpNode)
+	_, err := d.GetMatchingNodes(nodeToMap(lhs), assignmentOpNode)
 
 	return err
 }

pkg/yqlib/operator_multiply_test.go

@@ -13,51 +13,6 @@ var multiplyOperatorScenarios = []expressionScenario{
 			"D0, P[], (!!map)::{a: {also: me}, b: {also: me}}\n",
 		},
 	},
-	{
-		skipDoc:    true,
-		document:   "# b\nb:\n  # a\n  a: cat",
-		expression: "{} * .",
-		expected: []string{
-			"D0, P[], (!!map)::# b\nb:\n    # a\n    a: cat\n",
-		},
-	},
-	{
-		skipDoc:    true,
-		document:   "# b\nb:\n  # a\n  a: cat",
-		expression: ". * {}",
-		expected: []string{
-			"D0, P[], (!!map)::# b\nb:\n    # a\n    a: cat\n",
-		},
-	},
-	{
-		skipDoc:    true,
-		document:   `{a: &a { b: &b { c: &c cat } } }`,
-		expression: `{} * .`,
-		expected: []string{
-			"D0, P[], (!!map)::{a: &a {b: &b {c: &c cat}}}\n",
-		},
-	},
-	{
-		skipDoc:    true,
-		document:   `{a: 2, b: 5}`,
-		document2:  `{a: 3, b: 10}`,
-		expression: `.a * .b`,
-		expected: []string{
-			"D0, P[a], (!!int)::10\n",
-			"D0, P[a], (!!int)::20\n",
-			"D0, P[a], (!!int)::15\n",
-			"D0, P[a], (!!int)::30\n",
-		},
-	},
-	{
-		skipDoc:    true,
-		document:   `{a: 2}`,
-		document2:  `{b: 10}`,
-		expression: `select(fi ==0) * select(fi==1)`,
-		expected: []string{
-			"D0, P[], (!!map)::{a: 2, b: 10}\n",
-		},
-	},
 	{
 		skipDoc:    true,
 		expression: `{} * {"cat":"dog"}`,
@@ -124,10 +79,16 @@ var multiplyOperatorScenarios = []expressionScenario{
 	{
 		description:           "Merge keeps style of LHS",
 		dontFormatInputForDoc: true,
-		document:              "a: {things: great}\nb:\n  also: \"me\"",
+		document: `a: {things: great}
+b:
+  also: "me"
+`,
 		expression: `. * {"a":.b}`,
 		expected: []string{
-			"D0, P[], (!!map)::a: {things: great, also: \"me\"}\nb:\n    also: \"me\"\n",
+			`D0, P[], (!!map)::a: {things: great, also: "me"}
+b:
+    also: "me"
+`,
 		},
 	},
 	{
@@ -162,14 +123,6 @@ var multiplyOperatorScenarios = []expressionScenario{
 			"D0, P[a], (!!seq)::[{thing: two}]\n",
 		},
 	},
-	{
-		skipDoc:    true,
-		document:   `{a: {array: [1]}, b: {}}`,
-		expression: `.b *+ .a`,
-		expected: []string{
-			"D0, P[b], (!!map)::{array: [1]}\n",
-		},
-	},
 	{
 		description: "Merge, appending arrays",
 		document:    `{a: {array: [1, 2, animal: dog], value: coconut}, b: {array: [3, 4, animal: cat], value: banana}}`,

pkg/yqlib/operator_path.go

@@ -16,12 +16,12 @@ func createPathNodeFor(pathElement interface{}) *yaml.Node {
 	}
 }
 
-func getPathOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func getPathOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("GetPath")
 
 	var results = list.New()
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := matchingNodes.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		node := &yaml.Node{Kind: yaml.SequenceNode, Tag: "!!seq"}
 
@@ -35,5 +35,5 @@ func getPathOperator(d *dataTreeNavigator, context Context, expressionNode *Expr
 		results.PushBack(result)
 	}
 
-	return context.ChildContext(results), nil
+	return results, nil
 }

pkg/yqlib/operator_pipe.go

@@ -1,18 +1,11 @@
 package yqlib
 
-func pipeOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+import "container/list"
 
-	//lhs may update the variable context, we should pass that into the RHS
+func pipeOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
-	// BUT we still return the original context back (see jq)
+	lhs, err := d.GetMatchingNodes(matchingNodes, expressionNode.Lhs)
-	// https://stedolan.github.io/jq/manual/#Variable/SymbolicBindingOperator:...as$identifier|...
-
-	lhs, err := d.GetMatchingNodes(context, expressionNode.Lhs)
 	if err != nil {
-		return Context{}, err
+		return nil, err
 	}
-	rhs, err := d.GetMatchingNodes(lhs, expressionNode.Rhs)
+	return d.GetMatchingNodes(lhs, expressionNode.Rhs)
-	if err != nil {
-		return Context{}, err
-	}
-	return context.ChildContext(rhs.MatchingNodes), nil
 }

pkg/yqlib/operator_recursive_descent.go

@@ -11,20 +11,20 @@ type recursiveDescentPreferences struct {
 	RecurseArray        bool
 }
 
-func recursiveDescentOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func recursiveDescentOperator(d *dataTreeNavigator, matchMap *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	var results = list.New()
 
 	preferences := expressionNode.Operation.Preferences.(recursiveDescentPreferences)
-	err := recursiveDecent(d, results, context, preferences)
+	err := recursiveDecent(d, results, matchMap, preferences)
 	if err != nil {
-		return Context{}, err
+		return nil, err
 	}
 
-	return context.ChildContext(results), nil
+	return results, nil
 }
 
-func recursiveDecent(d *dataTreeNavigator, results *list.List, context Context, preferences recursiveDescentPreferences) error {
+func recursiveDecent(d *dataTreeNavigator, results *list.List, matchMap *list.List, preferences recursiveDescentPreferences) error {
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := matchMap.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 
 		candidate.Node = unwrapDoc(candidate.Node)
@@ -35,7 +35,7 @@ func recursiveDecent(d *dataTreeNavigator, results *list.List, context Context,
 		if candidate.Node.Kind != yaml.AliasNode && len(candidate.Node.Content) > 0 &&
 			(preferences.RecurseArray || candidate.Node.Kind != yaml.SequenceNode) {
 
-			children, err := splat(d, context.SingleChildContext(candidate), preferences.TraversePreferences)
+			children, err := splat(d, nodeToMap(candidate), preferences.TraversePreferences)
 
 			if err != nil {
 				return err

pkg/yqlib/operator_reduce.go

@@ -1,59 +0,0 @@
-package yqlib
-
-import (
-	"container/list"
-	"fmt"
-)
-
-func reduceOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
-	log.Debugf("-- reduceOp")
-	//.a as $var reduce (0; . + $var)
-	//lhs is the assignment operator
-	//rhs is the reduce block
-	// '.' refers to the current accumulator, initialised to 0
-	// $var references a single element from the .a
-
-	//ensure lhs is actually an assignment
-	//and rhs is a block (empty)
-	if expressionNode.Lhs.Operation.OperationType != assignVariableOpType {
-		return Context{}, fmt.Errorf("reduce must be given a variables assignment, got %v instead", expressionNode.Lhs.Operation.OperationType.Type)
-	} else if expressionNode.Rhs.Operation.OperationType != blockOpType {
-		return Context{}, fmt.Errorf("reduce must be given a block, got %v instead", expressionNode.Rhs.Operation.OperationType.Type)
-	}
-
-	arrayExpNode := expressionNode.Lhs.Lhs
-	array, err := d.GetMatchingNodes(context, arrayExpNode)
-
-	log.Debugf("array of %v things", array.MatchingNodes.Len())
-
-	if err != nil {
-		return Context{}, err
-	}
-
-	variableName := expressionNode.Lhs.Rhs.Operation.StringValue
-
-	initExp := expressionNode.Rhs.Lhs
-
-	accum, err := d.GetMatchingNodes(context, initExp)
-	if err != nil {
-		return Context{}, err
-	}
-
-	log.Debugf("with variable %v", variableName)
-
-	blockExp := expressionNode.Rhs.Rhs
-	for el := array.MatchingNodes.Front(); el != nil; el = el.Next() {
-		candidate := el.Value.(*CandidateNode)
-		log.Debugf("REDUCING WITH %v", NodeToString(candidate))
-		l := list.New()
-		l.PushBack(candidate)
-		accum.SetVariable(variableName, l)
-
-		accum, err = d.GetMatchingNodes(accum, blockExp)
-		if err != nil {
-			return Context{}, err
-		}
-	}
-
-	return accum, nil
-}

pkg/yqlib/operator_reduce_test.go

@@ -1,22 +0,0 @@
-package yqlib
-
-import (
-	"testing"
-)
-
-var reduceOperatorScenarios = []expressionScenario{
-	{
-		document:   `[10,2, 5, 3]`,
-		expression: `.[] as $item ireduce (0; . + $item)`,
-		expected: []string{
-			"D0, P[], (!!int)::20\n",
-		},
-	},
-}
-
-func TestReduceOperatorScenarios(t *testing.T) {
-	for _, tt := range reduceOperatorScenarios {
-		testScenario(t, &tt)
-	}
-	// documentScenarios(t, "Reduce", reduceOperatorScenarios)
-}

pkg/yqlib/operator_select.go

@@ -4,29 +4,28 @@ import (
 	"container/list"
 )
 
-func selectOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func selectOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 
 	log.Debugf("-- selectOperation")
 	var results = list.New()
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := matchingNodes.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
-		childContext := context.SingleChildContext(candidate)
+
-		childContext.DontAutoCreate = true
+		rhs, err := d.GetMatchingNodes(nodeToMap(candidate), expressionNode.Rhs)
-		rhs, err := d.GetMatchingNodes(childContext, expressionNode.Rhs)
 
 		if err != nil {
-			return Context{}, err
+			return nil, err
 		}
 
 		// grab the first value
-		first := rhs.MatchingNodes.Front()
+		first := rhs.Front()
 
 		if first != nil {
 			result := first.Value.(*CandidateNode)
 			includeResult, errDecoding := isTruthy(result)
 			if errDecoding != nil {
-				return Context{}, errDecoding
+				return nil, errDecoding
 			}
 
 			if includeResult {
@@ -34,5 +33,5 @@ func selectOperator(d *dataTreeNavigator, context Context, expressionNode *Expre
 			}
 		}
 	}
-	return context.ChildContext(results), nil
+	return results, nil
 }

pkg/yqlib/operator_select_test.go

@@ -14,14 +14,6 @@ var selectOperatorScenarios = []expressionScenario{
 			"D0, P[1], (!!str)::goat\n",
 		},
 	},
-	{
-		skipDoc:    true,
-		document:   `[{animal: cat, legs: {cool: true}}, {animal: fish}]`,
-		expression: `(.[] | select(.legs.cool == true).canWalk) = true | (.[] | .alive.things) = "yes"`,
-		expected: []string{
-			"D0, P[], (doc)::[{animal: cat, legs: {cool: true}, canWalk: true, alive: {things: yes}}, {animal: fish, alive: {things: yes}}]\n",
-		},
-	},
 	{
 		skipDoc:    true,
 		document:   `[hot, fot, dog]`,

pkg/yqlib/operator_self.go

@@ -1,5 +1,7 @@
 package yqlib
 
-func selfOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+import "container/list"
-	return context, nil
+
+func selfOperator(d *dataTreeNavigator, matchMap *list.List, expressionNode *ExpressionNode) (*list.List, error) {
+	return matchMap, nil
 }

pkg/yqlib/operator_sort_keys.go

@@ -1,32 +1,33 @@
 package yqlib
 
 import (
+	"container/list"
 	"sort"
 
 	yaml "gopkg.in/yaml.v3"
 )
 
-func sortKeysOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func sortKeysOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := matchingNodes.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
-		rhs, err := d.GetMatchingNodes(context.SingleChildContext(candidate), expressionNode.Rhs)
+		rhs, err := d.GetMatchingNodes(nodeToMap(candidate), expressionNode.Rhs)
 		if err != nil {
-			return Context{}, err
+			return nil, err
 		}
 
-		for childEl := rhs.MatchingNodes.Front(); childEl != nil; childEl = childEl.Next() {
+		for childEl := rhs.Front(); childEl != nil; childEl = childEl.Next() {
 			node := unwrapDoc(childEl.Value.(*CandidateNode).Node)
 			if node.Kind == yaml.MappingNode {
 				sortKeys(node)
 			}
 			if err != nil {
-				return Context{}, err
+				return nil, err
 			}
 		}
 
 	}
-	return context, nil
+	return matchingNodes, nil
 }
 
 func sortKeys(node *yaml.Node) {

pkg/yqlib/operator_split_document.go

@@ -1,14 +1,18 @@
 package yqlib
 
-func splitDocumentOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+import (
+	"container/list"
+)
+
+func splitDocumentOperator(d *dataTreeNavigator, matchMap *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("-- splitDocumentOperator")
 
 	var index uint = 0
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := matchMap.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		candidate.Document = index
 		index = index + 1
 	}
 
-	return context, nil
+	return matchMap, nil
 }

pkg/yqlib/operator_strings.go

@@ -8,32 +8,32 @@ import (
 	"gopkg.in/yaml.v3"
 )
 
-func joinStringOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func joinStringOperator(d *dataTreeNavigator, matchMap *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("-- joinStringOperator")
 	joinStr := ""
 
-	rhs, err := d.GetMatchingNodes(context, expressionNode.Rhs)
+	rhs, err := d.GetMatchingNodes(matchMap, expressionNode.Rhs)
 	if err != nil {
-		return Context{}, err
+		return nil, err
 	}
-	if rhs.MatchingNodes.Front() != nil {
+	if rhs.Front() != nil {
-		joinStr = rhs.MatchingNodes.Front().Value.(*CandidateNode).Node.Value
+		joinStr = rhs.Front().Value.(*CandidateNode).Node.Value
 	}
 
 	var results = list.New()
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := matchMap.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		node := unwrapDoc(candidate.Node)
 		if node.Kind != yaml.SequenceNode {
-			return Context{}, fmt.Errorf("Cannot join with %v, can only join arrays of scalars", node.Tag)
+			return nil, fmt.Errorf("Cannot join with %v, can only join arrays of scalars", node.Tag)
 		}
 		targetNode := join(node.Content, joinStr)
 		result := candidate.CreateChild(nil, targetNode)
 		results.PushBack(result)
 	}
 
-	return context.ChildContext(results), nil
+	return results, nil
 }
 
 func join(content []*yaml.Node, joinStr string) *yaml.Node {
@@ -49,35 +49,35 @@ func join(content []*yaml.Node, joinStr string) *yaml.Node {
 	return &yaml.Node{Kind: yaml.ScalarNode, Value: strings.Join(stringsToJoin, joinStr), Tag: "!!str"}
 }
 
-func splitStringOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func splitStringOperator(d *dataTreeNavigator, matchMap *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("-- splitStringOperator")
 	splitStr := ""
 
-	rhs, err := d.GetMatchingNodes(context, expressionNode.Rhs)
+	rhs, err := d.GetMatchingNodes(matchMap, expressionNode.Rhs)
 	if err != nil {
-		return Context{}, err
+		return nil, err
 	}
-	if rhs.MatchingNodes.Front() != nil {
+	if rhs.Front() != nil {
-		splitStr = rhs.MatchingNodes.Front().Value.(*CandidateNode).Node.Value
+		splitStr = rhs.Front().Value.(*CandidateNode).Node.Value
 	}
 
 	var results = list.New()
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := matchMap.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		node := unwrapDoc(candidate.Node)
 		if node.Tag == "!!null" {
 			continue
 		}
 		if node.Tag != "!!str" {
-			return Context{}, fmt.Errorf("Cannot split %v, can only split strings", node.Tag)
+			return nil, fmt.Errorf("Cannot split %v, can only split strings", node.Tag)
 		}
 		targetNode := split(node.Value, splitStr)
 		result := candidate.CreateChild(nil, targetNode)
 		results.PushBack(result)
 	}
 
-	return context.ChildContext(results), nil
+	return results, nil
 }
 
 func split(value string, spltStr string) *yaml.Node {

pkg/yqlib/operator_style.go

@@ -26,43 +26,43 @@ func parseStyle(customStyle string) (yaml.Style, error) {
 	return 0, nil
 }
 
-func assignStyleOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func assignStyleOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 
 	log.Debugf("AssignStyleOperator: %v")
 	var style yaml.Style
 	if !expressionNode.Operation.UpdateAssign {
-		rhs, err := d.GetMatchingNodes(context, expressionNode.Rhs)
+		rhs, err := d.GetMatchingNodes(matchingNodes, expressionNode.Rhs)
 		if err != nil {
-			return Context{}, err
+			return nil, err
 		}
 
-		if rhs.MatchingNodes.Front() != nil {
+		if rhs.Front() != nil {
-			style, err = parseStyle(rhs.MatchingNodes.Front().Value.(*CandidateNode).Node.Value)
+			style, err = parseStyle(rhs.Front().Value.(*CandidateNode).Node.Value)
 			if err != nil {
-				return Context{}, err
+				return nil, err
 			}
 		}
 	}
 
-	lhs, err := d.GetMatchingNodes(context, expressionNode.Lhs)
+	lhs, err := d.GetMatchingNodes(matchingNodes, expressionNode.Lhs)
 
 	if err != nil {
-		return Context{}, err
+		return nil, err
 	}
 
-	for el := lhs.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := lhs.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		log.Debugf("Setting style of : %v", candidate.GetKey())
 		if expressionNode.Operation.UpdateAssign {
-			rhs, err := d.GetMatchingNodes(context.SingleChildContext(candidate), expressionNode.Rhs)
+			rhs, err := d.GetMatchingNodes(nodeToMap(candidate), expressionNode.Rhs)
 			if err != nil {
-				return Context{}, err
+				return nil, err
 			}
 
-			if rhs.MatchingNodes.Front() != nil {
+			if rhs.Front() != nil {
-				style, err = parseStyle(rhs.MatchingNodes.Front().Value.(*CandidateNode).Node.Value)
+				style, err = parseStyle(rhs.Front().Value.(*CandidateNode).Node.Value)
 				if err != nil {
-					return Context{}, err
+					return nil, err
 				}
 			}
 		}
@@ -70,15 +70,15 @@ func assignStyleOperator(d *dataTreeNavigator, context Context, expressionNode *
 		candidate.Node.Style = style
 	}
 
-	return context, nil
+	return matchingNodes, nil
 }
 
-func getStyleOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func getStyleOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("GetStyleOperator")
 
 	var results = list.New()
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := matchingNodes.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		var style string
 		switch candidate.Node.Style {
@@ -104,5 +104,5 @@ func getStyleOperator(d *dataTreeNavigator, context Context, expressionNode *Exp
 		results.PushBack(result)
 	}
 
-	return context.ChildContext(results), nil
+	return results, nil
 }

pkg/yqlib/operator_tag.go

@@ -6,58 +6,58 @@ import (
 	yaml "gopkg.in/yaml.v3"
 )
 
-func assignTagOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func assignTagOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 
 	log.Debugf("AssignTagOperator: %v")
 	tag := ""
 
 	if !expressionNode.Operation.UpdateAssign {
-		rhs, err := d.GetMatchingNodes(context, expressionNode.Rhs)
+		rhs, err := d.GetMatchingNodes(matchingNodes, expressionNode.Rhs)
 		if err != nil {
-			return Context{}, err
+			return nil, err
 		}
 
-		if rhs.MatchingNodes.Front() != nil {
+		if rhs.Front() != nil {
-			tag = rhs.MatchingNodes.Front().Value.(*CandidateNode).Node.Value
+			tag = rhs.Front().Value.(*CandidateNode).Node.Value
 		}
 	}
 
-	lhs, err := d.GetMatchingNodes(context, expressionNode.Lhs)
+	lhs, err := d.GetMatchingNodes(matchingNodes, expressionNode.Lhs)
 
 	if err != nil {
-		return Context{}, err
+		return nil, err
 	}
 
-	for el := lhs.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := lhs.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
 		log.Debugf("Setting tag of : %v", candidate.GetKey())
 		if expressionNode.Operation.UpdateAssign {
-			rhs, err := d.GetMatchingNodes(context.SingleChildContext(candidate), expressionNode.Rhs)
+			rhs, err := d.GetMatchingNodes(nodeToMap(candidate), expressionNode.Rhs)
 			if err != nil {
-				return Context{}, err
+				return nil, err
 			}
 
-			if rhs.MatchingNodes.Front() != nil {
+			if rhs.Front() != nil {
-				tag = rhs.MatchingNodes.Front().Value.(*CandidateNode).Node.Value
+				tag = rhs.Front().Value.(*CandidateNode).Node.Value
 			}
 		}
 		unwrapDoc(candidate.Node).Tag = tag
 	}
 
-	return context, nil
+	return matchingNodes, nil
 }
 
-func getTagOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func getTagOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debugf("GetTagOperator")
 
 	var results = list.New()
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := 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)
 		results.PushBack(result)
 	}
 
-	return context.ChildContext(results), nil
+	return results, nil
 }

pkg/yqlib/operator_traverse_path.go

@@ -13,29 +13,28 @@ type traversePreferences struct {
 	DontFollowAlias bool
 	IncludeMapKeys  bool
 	DontAutoCreate  bool // by default, we automatically create entries on the fly.
-	DontIncludeMapValues bool
 }
 
-func splat(d *dataTreeNavigator, context Context, prefs traversePreferences) (Context, error) {
+func splat(d *dataTreeNavigator, matches *list.List, prefs traversePreferences) (*list.List, error) {
-	return traverseNodesWithArrayIndices(context, make([]*yaml.Node, 0), prefs)
+	return traverseNodesWithArrayIndices(matches, make([]*yaml.Node, 0), prefs)
 }
 
-func traversePathOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func traversePathOperator(d *dataTreeNavigator, matchMap *list.List, expressionNode *ExpressionNode) (*list.List, error) {
-	log.Debugf("-- traversePathOperator")
+	log.Debugf("-- Traversing")
-	var matches = list.New()
+	var matchingNodeMap = list.New()
 
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := matchMap.Front(); el != nil; el = el.Next() {
-		newNodes, err := traverse(d, context, el.Value.(*CandidateNode), expressionNode.Operation)
+		newNodes, err := traverse(d, el.Value.(*CandidateNode), expressionNode.Operation)
 		if err != nil {
-			return Context{}, err
+			return nil, err
 		}
-		matches.PushBackList(newNodes)
+		matchingNodeMap.PushBackList(newNodes)
 	}
 
-	return context.ChildContext(matches), nil
+	return matchingNodeMap, nil
 }
 
-func traverse(d *dataTreeNavigator, context Context, matchingNode *CandidateNode, operation *Operation) (*list.List, error) {
+func traverse(d *dataTreeNavigator, matchingNode *CandidateNode, operation *Operation) (*list.List, error) {
 	log.Debug("Traversing %v", NodeToString(matchingNode))
 	value := matchingNode.Node
 
@@ -56,7 +55,7 @@ func traverse(d *dataTreeNavigator, context Context, matchingNode *CandidateNode
 	switch value.Kind {
 	case yaml.MappingNode:
 		log.Debug("its a map with %v entries", len(value.Content)/2)
-		return traverseMap(context, matchingNode, operation.StringValue, operation.Preferences.(traversePreferences), false)
+		return traverseMap(matchingNode, operation.StringValue, operation.Preferences.(traversePreferences), false)
 
 	case yaml.SequenceNode:
 		log.Debug("its a sequence of %v things!", len(value.Content))
@@ -65,59 +64,43 @@ func traverse(d *dataTreeNavigator, context Context, matchingNode *CandidateNode
 	case yaml.AliasNode:
 		log.Debug("its an alias!")
 		matchingNode.Node = matchingNode.Node.Alias
-		return traverse(d, context, matchingNode, operation)
+		return traverse(d, matchingNode, operation)
 	case yaml.DocumentNode:
 		log.Debug("digging into doc node")
 
-		return traverse(d, context, matchingNode.CreateChild(nil, matchingNode.Node.Content[0]), operation)
+		return traverse(d, matchingNode.CreateChild(nil, matchingNode.Node.Content[0]), operation)
 	default:
 		return list.New(), nil
 	}
 }
 
-func traverseArrayOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func traverseArrayOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
-
-	//lhs may update the variable context, we should pass that into the RHS
-	// BUT we still return the original context back (see jq)
-	// https://stedolan.github.io/jq/manual/#Variable/SymbolicBindingOperator:...as$identifier|...
-
-	lhs, err := d.GetMatchingNodes(context, expressionNode.Lhs)
-	if err != nil {
-		return Context{}, err
-	}
-
 	// rhs is a collect expression that will yield indexes to retreive of the arrays
 
-	rhs, err := d.GetMatchingNodes(context, expressionNode.Rhs)
+	rhs, err := d.GetMatchingNodes(matchingNodes, expressionNode.Rhs)
 	if err != nil {
-		return Context{}, err
+		return nil, err
 	}
 
-	var indicesToTraverse = rhs.MatchingNodes.Front().Value.(*CandidateNode).Node.Content
+	var indicesToTraverse = rhs.Front().Value.(*CandidateNode).Node.Content
-
+	return traverseNodesWithArrayIndices(matchingNodes, indicesToTraverse, traversePreferences{})
-	//now we traverse the result of the lhs against the indices we found
-	result, err := traverseNodesWithArrayIndices(lhs, indicesToTraverse, traversePreferences{})
-	if err != nil {
-		return Context{}, err
-	}
-	return context.ChildContext(result.MatchingNodes), nil
 }
 
-func traverseNodesWithArrayIndices(context Context, indicesToTraverse []*yaml.Node, prefs traversePreferences) (Context, error) {
+func traverseNodesWithArrayIndices(matchingNodes *list.List, indicesToTraverse []*yaml.Node, prefs traversePreferences) (*list.List, error) {
 	var matchingNodeMap = list.New()
-	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := matchingNodes.Front(); el != nil; el = el.Next() {
 		candidate := el.Value.(*CandidateNode)
-		newNodes, err := traverseArrayIndices(context, candidate, indicesToTraverse, prefs)
+		newNodes, err := traverseArrayIndices(candidate, indicesToTraverse, prefs)
 		if err != nil {
-			return Context{}, err
+			return nil, err
 		}
 		matchingNodeMap.PushBackList(newNodes)
 	}
 
-	return context.ChildContext(matchingNodeMap), nil
+	return matchingNodeMap, nil
 }
 
-func traverseArrayIndices(context Context, matchingNode *CandidateNode, indicesToTraverse []*yaml.Node, prefs traversePreferences) (*list.List, error) { // call this if doc / alias like the other traverse
+func traverseArrayIndices(matchingNode *CandidateNode, indicesToTraverse []*yaml.Node, prefs traversePreferences) (*list.List, error) { // call this if doc / alias like the other traverse
 	node := matchingNode.Node
 	if node.Tag == "!!null" {
 		log.Debugf("OperatorArrayTraverse got a null - turning it into an empty array")
@@ -128,28 +111,28 @@ func traverseArrayIndices(context Context, matchingNode *CandidateNode, indicesT
 
 	if node.Kind == yaml.AliasNode {
 		matchingNode.Node = node.Alias
-		return traverseArrayIndices(context, matchingNode, indicesToTraverse, prefs)
+		return traverseArrayIndices(matchingNode, indicesToTraverse, prefs)
 	} else if node.Kind == yaml.SequenceNode {
 		return traverseArrayWithIndices(matchingNode, indicesToTraverse)
 	} else if node.Kind == yaml.MappingNode {
-		return traverseMapWithIndices(context, matchingNode, indicesToTraverse, prefs)
+		return traverseMapWithIndices(matchingNode, indicesToTraverse, prefs)
 	} else if node.Kind == yaml.DocumentNode {
-		return traverseArrayIndices(context, matchingNode.CreateChild(nil, matchingNode.Node.Content[0]), indicesToTraverse, prefs)
+		return traverseArrayIndices(matchingNode.CreateChild(nil, matchingNode.Node.Content[0]), indicesToTraverse, prefs)
 	}
 	log.Debugf("OperatorArrayTraverse skipping %v as its a %v", matchingNode, node.Tag)
 	return list.New(), nil
 }
 
-func traverseMapWithIndices(context Context, candidate *CandidateNode, indices []*yaml.Node, prefs traversePreferences) (*list.List, error) {
+func traverseMapWithIndices(candidate *CandidateNode, indices []*yaml.Node, prefs traversePreferences) (*list.List, error) {
 	if len(indices) == 0 {
-		return traverseMap(context, candidate, "", prefs, true)
+		return traverseMap(candidate, "", prefs, true)
 	}
 
 	var matchingNodeMap = list.New()
 
 	for _, indexNode := range indices {
 		log.Debug("traverseMapWithIndices: %v", indexNode.Value)
-		newNodes, err := traverseMap(context, candidate, indexNode.Value, prefs, false)
+		newNodes, err := traverseMap(candidate, indexNode.Value, prefs, false)
 		if err != nil {
 			return nil, err
 		}
@@ -204,7 +187,7 @@ func keyMatches(key *yaml.Node, wantedKey string) bool {
 	return matchKey(key.Value, wantedKey)
 }
 
-func traverseMap(context Context, matchingNode *CandidateNode, key string, prefs traversePreferences, splat bool) (*list.List, error) {
+func traverseMap(matchingNode *CandidateNode, key string, prefs traversePreferences, splat bool) (*list.List, error) {
 	var newMatches = orderedmap.NewOrderedMap()
 	err := doTraverseMap(newMatches, matchingNode, key, prefs, splat)
 
@@ -212,25 +195,14 @@ func traverseMap(context Context, matchingNode *CandidateNode, key string, prefs
 		return nil, err
 	}
 
-	if !prefs.DontAutoCreate && !context.DontAutoCreate && newMatches.Len() == 0 {
+	if !prefs.DontAutoCreate && newMatches.Len() == 0 {
 		//no matches, create one automagically
 		valueNode := &yaml.Node{Tag: "!!null", Kind: yaml.ScalarNode, Value: "null"}
-		keyNode := &yaml.Node{Kind: yaml.ScalarNode, Value: key}
 		node := matchingNode.Node
-		node.Content = append(node.Content, keyNode, valueNode)
+		node.Content = append(node.Content, &yaml.Node{Kind: yaml.ScalarNode, Value: key}, valueNode)
-
-		if prefs.IncludeMapKeys {
-			log.Debug("including key")
-			candidateNode := matchingNode.CreateChild(key, 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)
 		newMatches.Set(candidateNode.GetKey(), candidateNode)
 	}
-	}
 
 	results := list.New()
 	i := 0
@@ -265,18 +237,13 @@ func doTraverseMap(newMatches *orderedmap.OrderedMap, candidate *CandidateNode,
 		} else if splat || keyMatches(key, wantedKey) {
 			log.Debug("MATCHED")
 			if prefs.IncludeMapKeys {
-				log.Debug("including key")
 				candidateNode := candidate.CreateChild(key.Value, 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)
 			newMatches.Set(candidateNode.GetKey(), candidateNode)
 		}
 	}
-	}
 
 	return nil
 }

pkg/yqlib/operator_traverse_path_test.go

@@ -47,30 +47,13 @@ var traversePathOperatorScenarios = []expressionScenario{
 	},
 	{
 		description:    "Special characters",
-		subdescription: "Use quotes with brackets around path elements with special characters",
+		subdescription: "Use quotes around path elements with special characters",
 		document:       `{"{}": frog}`,
-		expression:     `.["{}"]`,
+		expression:     `."{}"`,
 		expected: []string{
 			"D0, P[{}], (!!str)::frog\n",
 		},
 	},
-	{
-		description:    "Keys with spaces",
-		subdescription: "Use quotes with brackets around path elements with special characters",
-		document:       `{"red rabbit": frog}`,
-		expression:     `.["red rabbit"]`,
-		expected: []string{
-			"D0, P[red rabbit], (!!str)::frog\n",
-		},
-	},
-	{
-		skipDoc:    true,
-		document:   `{"flying fox": frog}`,
-		expression: `.["flying fox"]`,
-		expected: []string{
-			"D0, P[flying fox], (!!str)::frog\n",
-		},
-	},
 	{
 		description:    "Dynamic keys",
 		subdescription: `Expressions within [] can be used to dynamically lookup / calculate keys`,
@@ -80,14 +63,6 @@ var traversePathOperatorScenarios = []expressionScenario{
 			"D0, P[apple], (!!str)::crispy yum\n",
 		},
 	},
-	{
-		skipDoc:    true,
-		document:   `{b: apple, fruit: {apple: yum, banana: smooth}}`,
-		expression: `.fruit[.b]`,
-		expected: []string{
-			"D0, P[fruit apple], (!!str)::yum\n",
-		},
-	},
 	{
 		description:    "Children don't exist",
 		subdescription: "Nodes are added dynamically while traversing",
@@ -108,7 +83,7 @@ var traversePathOperatorScenarios = []expressionScenario{
 	{
 		skipDoc:    true,
 		document:   `{}`,
-		expression: `.a[1]`,
+		expression: `.a.[1]`,
 		expected: []string{
 			"D0, P[a 1], (!!null)::null\n",
 		},
@@ -179,7 +154,7 @@ var traversePathOperatorScenarios = []expressionScenario{
 	{
 		skipDoc:    true,
 		document:   `{a: &cat {c: frog}, b: *cat}`,
-		expression: `.b[]`,
+		expression: `.b.[]`,
 		expected: []string{
 			"D0, P[b c], (!!str)::frog\n",
 		},
@@ -261,7 +236,7 @@ var traversePathOperatorScenarios = []expressionScenario{
 	{
 		skipDoc:    true,
 		document:   mergeDocSample,
-		expression: `.foobar[]`,
+		expression: `.foobar.[]`,
 		expected: []string{
 			"D0, P[foobar c], (!!str)::foo_c\n",
 			"D0, P[foobar a], (!!str)::foo_a\n",
@@ -323,7 +298,7 @@ var traversePathOperatorScenarios = []expressionScenario{
 	{
 		skipDoc:    true,
 		document:   mergeDocSample,
-		expression: `.foobarList[]`,
+		expression: `.foobarList.[]`,
 		expected: []string{
 			"D0, P[foobarList b], (!!str)::bar_b\n",
 			"D0, P[foobarList a], (!!str)::foo_a\n",
@@ -369,7 +344,7 @@ var traversePathOperatorScenarios = []expressionScenario{
 	{
 		skipDoc:    true,
 		document:   `{a: [a,b,c]}`,
-		expression: `.a[0, 2]`,
+		expression: `.a.[0, 2]`,
 		expected: []string{
 			"D0, P[a 0], (!!str)::a\n",
 			"D0, P[a 2], (!!str)::c\n",
@@ -386,7 +361,7 @@ var traversePathOperatorScenarios = []expressionScenario{
 	{
 		skipDoc:    true,
 		document:   `{a: [a,b,c]}`,
-		expression: `.a[-1]`,
+		expression: `.a.[-1]`,
 		expected: []string{
 			"D0, P[a -1], (!!str)::c\n",
 		},
@@ -402,7 +377,7 @@ var traversePathOperatorScenarios = []expressionScenario{
 	{
 		skipDoc:    true,
 		document:   `{a: [a,b,c]}`,
-		expression: `.a[-2]`,
+		expression: `.a.[-2]`,
 		expected: []string{
 			"D0, P[a -2], (!!str)::b\n",
 		},
@@ -420,7 +395,7 @@ var traversePathOperatorScenarios = []expressionScenario{
 	{
 		skipDoc:    true,
 		document:   `{a: [a,b,c]}`,
-		expression: `.a[]`,
+		expression: `.a.[]`,
 		expected: []string{
 			"D0, P[a 0], (!!str)::a\n",
 			"D0, P[a 1], (!!str)::b\n",
@@ -443,5 +418,5 @@ func TestTraversePathOperatorScenarios(t *testing.T) {
 	for _, tt := range traversePathOperatorScenarios {
 		testScenario(t, &tt)
 	}
-	documentScenarios(t, "Traverse (Read)", traversePathOperatorScenarios)
+	documentScenarios(t, "Traverse", traversePathOperatorScenarios)
 }

pkg/yqlib/operator_union.go

@@ -1,17 +1,19 @@
 package yqlib
 
-func unionOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+import "container/list"
-	lhs, err := d.GetMatchingNodes(context, expressionNode.Lhs)
+
+func unionOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
+	lhs, err := d.GetMatchingNodes(matchingNodes, expressionNode.Lhs)
 	if err != nil {
-		return Context{}, err
+		return nil, err
 	}
-	rhs, err := d.GetMatchingNodes(context, expressionNode.Rhs)
+	rhs, err := d.GetMatchingNodes(matchingNodes, expressionNode.Rhs)
 	if err != nil {
-		return Context{}, err
+		return nil, err
 	}
-	for el := rhs.MatchingNodes.Front(); el != nil; el = el.Next() {
+	for el := rhs.Front(); el != nil; el = el.Next() {
 		node := el.Value.(*CandidateNode)
-		lhs.MatchingNodes.PushBack(node)
+		lhs.PushBack(node)
 	}
 	return lhs, nil
 }

pkg/yqlib/operator_value.go

@@ -1,6 +1,8 @@
 package yqlib
 
-func valueOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+import "container/list"
+
+func valueOperator(d *dataTreeNavigator, matchMap *list.List, expressionNode *ExpressionNode) (*list.List, error) {
 	log.Debug("value = %v", expressionNode.Operation.CandidateNode.Node.Value)
-	return context.SingleChildContext(expressionNode.Operation.CandidateNode), nil
+	return nodeToMap(expressionNode.Operation.CandidateNode), nil
 }

pkg/yqlib/operator_variables.go

@@ -1,29 +0,0 @@
-package yqlib
-
-import (
-	"container/list"
-	"fmt"
-)
-
-func getVariableOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
-	variableName := expressionNode.Operation.StringValue
-	log.Debug("getVariableOperator %v", variableName)
-	result := context.GetVariable(variableName)
-	if result == nil {
-		result = list.New()
-	}
-	return context.ChildContext(result), nil
-}
-
-func assignVariableOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
-	lhs, err := d.GetMatchingNodes(context, expressionNode.Lhs)
-	if err != nil {
-		return Context{}, nil
-	}
-	if expressionNode.Rhs.Operation.OperationType.Type != "GET_VARIABLE" {
-		return Context{}, fmt.Errorf("RHS of 'as' operator must be a variable name e.g. $foo")
-	}
-	variableName := expressionNode.Rhs.Operation.StringValue
-	context.SetVariable(variableName, lhs.MatchingNodes)
-	return context, nil
-}

pkg/yqlib/operator_variables_test.go

@@ -1,45 +0,0 @@
-package yqlib
-
-import (
-	"testing"
-)
-
-var variableOperatorScenarios = []expressionScenario{
-	{
-		description: "Single value variable",
-		document:    `a: cat`,
-		expression:  `.a as $foo | $foo`,
-		expected: []string{
-			"D0, P[a], (!!str)::cat\n",
-		},
-	},
-	{
-		description: "Multi value variable",
-		document:    `[cat, dog]`,
-		expression:  `.[] as $foo | $foo`,
-		expected: []string{
-			"D0, P[0], (!!str)::cat\n",
-			"D0, P[1], (!!str)::dog\n",
-		},
-	},
-	{
-		description:    "Using variables as a lookup",
-		subdescription: "Example taken from [jq](https://stedolan.github.io/jq/manual/#Variable/SymbolicBindingOperator:...as$identifier|...)",
-		document: `{"posts": [{"title": "Frist psot", "author": "anon"},
-		{"title": "A well-written article", "author": "person1"}],
-"realnames": {"anon": "Anonymous Coward",
-				"person1": "Person McPherson"}}`,
-		expression: `.realnames as $names | .posts[] | {"title":.title, "author": $names[.author]}`,
-		expected: []string{
-			"D0, P[], (!!map)::title: \"Frist psot\"\nauthor: \"Anonymous Coward\"\n",
-			"D0, P[], (!!map)::title: \"A well-written article\"\nauthor: \"Person McPherson\"\n",
-		},
-	},
-}
-
-func TestVariableOperatorScenarios(t *testing.T) {
-	for _, tt := range variableOperatorScenarios {
-		testScenario(t, &tt)
-	}
-	documentScenarios(t, "Variable Operators", variableOperatorScenarios)
-}

pkg/yqlib/operators.go

@@ -4,11 +4,10 @@ import (
 	"container/list"
 	"fmt"
 
-	"github.com/jinzhu/copier"
 	"gopkg.in/yaml.v3"
 )
 
-type operatorHandler func(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error)
+type operatorHandler func(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error)
 
 func unwrapDoc(node *yaml.Node) *yaml.Node {
 	if node.Kind == yaml.DocumentNode {
@@ -17,67 +16,8 @@ func unwrapDoc(node *yaml.Node) *yaml.Node {
 	return node
 }
 
-func emptyOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+func emptyOperator(d *dataTreeNavigator, matchingNodes *list.List, expressionNode *ExpressionNode) (*list.List, error) {
-	context.MatchingNodes = list.New()
+	return list.New(), nil
-	return context, nil
-}
-
-type crossFunctionCalculation func(d *dataTreeNavigator, context Context, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error)
-
-func doCrossFunc(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode, calculation crossFunctionCalculation) (Context, error) {
-	var results = list.New()
-	lhs, err := d.GetMatchingNodes(context, expressionNode.Lhs)
-	if err != nil {
-		return Context{}, err
-	}
-	log.Debugf("crossFunction LHS len: %v", lhs.MatchingNodes.Len())
-
-	rhs, err := d.GetMatchingNodes(context, expressionNode.Rhs)
-
-	if err != nil {
-		return Context{}, err
-	}
-
-	for el := lhs.MatchingNodes.Front(); el != nil; el = el.Next() {
-		lhsCandidate := el.Value.(*CandidateNode)
-
-		for rightEl := rhs.MatchingNodes.Front(); rightEl != nil; rightEl = rightEl.Next() {
-			log.Debugf("Applying calc")
-			rhsCandidate := rightEl.Value.(*CandidateNode)
-			resultCandidate, err := calculation(d, context, lhsCandidate, rhsCandidate)
-			if err != nil {
-				return Context{}, err
-			}
-			results.PushBack(resultCandidate)
-		}
-
-	}
-	return context.ChildContext(results), nil
-}
-
-func crossFunction(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode, calculation crossFunctionCalculation) (Context, error) {
-	var results = list.New()
-
-	var evaluateAllTogether = true
-	for matchEl := context.MatchingNodes.Front(); matchEl != nil; matchEl = matchEl.Next() {
-		evaluateAllTogether = evaluateAllTogether && matchEl.Value.(*CandidateNode).EvaluateTogether
-		if !evaluateAllTogether {
-			break
-		}
-	}
-	if evaluateAllTogether {
-		return doCrossFunc(d, context, expressionNode, calculation)
-	}
-
-	for matchEl := context.MatchingNodes.Front(); matchEl != nil; matchEl = matchEl.Next() {
-		innerResults, err := doCrossFunc(d, context.SingleChildContext(matchEl.Value.(*CandidateNode)), expressionNode, calculation)
-		if err != nil {
-			return Context{}, err
-		}
-		results.PushBackList(innerResults.MatchingNodes)
-	}
-
-	return context.ChildContext(results), nil
 }
 
 func createBooleanCandidate(owner *CandidateNode, value bool) *CandidateNode {
@@ -89,25 +29,22 @@ func createBooleanCandidate(owner *CandidateNode, value bool) *CandidateNode {
 	return owner.CreateChild(nil, node)
 }
 
-func createTraversalTree(path []interface{}, traversePrefs traversePreferences, targetKey bool) *ExpressionNode {
+func nodeToMap(candidate *CandidateNode) *list.List {
+	elMap := list.New()
+	elMap.PushBack(candidate)
+	return elMap
+}
+
+func createTraversalTree(path []interface{}, traversePrefs traversePreferences) *ExpressionNode {
 	if len(path) == 0 {
 		return &ExpressionNode{Operation: &Operation{OperationType: selfReferenceOpType}}
 	} else if len(path) == 1 {
-		lastPrefs := traversePrefs
+		return &ExpressionNode{Operation: &Operation{OperationType: traversePathOpType, Preferences: traversePrefs, Value: path[0], StringValue: fmt.Sprintf("%v", path[0])}}
-		if targetKey {
-			err := copier.Copy(&lastPrefs, traversePrefs)
-			if err != nil {
-				panic(err)
-			}
-			lastPrefs.IncludeMapKeys = true
-			lastPrefs.DontIncludeMapValues = true
-		}
-		return &ExpressionNode{Operation: &Operation{OperationType: traversePathOpType, Preferences: lastPrefs, Value: path[0], StringValue: fmt.Sprintf("%v", path[0])}}
 	}
 
 	return &ExpressionNode{
 		Operation: &Operation{OperationType: shortPipeOpType},
-		Lhs:       createTraversalTree(path[0:1], traversePrefs, false),
+		Lhs:       createTraversalTree(path[0:1], traversePrefs),
-		Rhs:       createTraversalTree(path[1:], traversePrefs, targetKey),
+		Rhs:       createTraversalTree(path[1:], traversePrefs),
 	}
 }

pkg/yqlib/operators_test.go

@@ -27,6 +27,7 @@ type expressionScenario struct {
 }
 
 func testScenario(t *testing.T, s *expressionScenario) {
+	var results *list.List
 	var err error
 
 	node, err := NewExpressionParser().ParseExpression(s.expression)
@@ -65,13 +66,13 @@ func testScenario(t *testing.T, s *expressionScenario) {
 		os.Setenv("myenv", s.environmentVariable)
 	}
 
-	context, err := NewDataTreeNavigator().GetMatchingNodes(Context{MatchingNodes: inputs}, node)
+	results, err = NewDataTreeNavigator().GetMatchingNodes(inputs, node)
 
 	if err != nil {
 		t.Error(fmt.Errorf("%v: %v", err, s.expression))
 		return
 	}
-	test.AssertResultComplexWithContext(t, s.expected, resultsToString(context.MatchingNodes), fmt.Sprintf("exp: %v\ndoc: %v", s.expression, s.document))
+	test.AssertResultComplexWithContext(t, s.expected, resultsToString(results), fmt.Sprintf("exp: %v\ndoc: %v", s.expression, s.document))
 }
 
 func resultsToString(results *list.List) []string {
@@ -251,12 +252,12 @@ func documentOutput(t *testing.T, w *bufio.Writer, s expressionScenario, formatt
 
 	}
 
-	context, err := NewDataTreeNavigator().GetMatchingNodes(Context{MatchingNodes: inputs}, node)
+	results, err := NewDataTreeNavigator().GetMatchingNodes(inputs, node)
 	if err != nil {
 		t.Error(err, s.expression)
 	}
 
-	err = printer.PrintResults(context.MatchingNodes)
+	err = printer.PrintResults(results)
 	if err != nil {
 		t.Error(err, s.expression)
 	}

pkg/yqlib/printer.go

@@ -74,14 +74,14 @@ func (p *resultsPrinter) safelyFlush(writer *bufio.Writer) {
 
 func (p *resultsPrinter) PrintResults(matchingNodes *list.List) error {
 	log.Debug("PrintResults for %v matches", matchingNodes.Len())
+	var err error
 	if p.outputToJSON {
 		explodeOp := Operation{OperationType: explodeOpType}
 		explodeNode := ExpressionNode{Operation: &explodeOp}
-		context, err := p.treeNavigator.GetMatchingNodes(Context{MatchingNodes: matchingNodes}, &explodeNode)
+		matchingNodes, err = p.treeNavigator.GetMatchingNodes(matchingNodes, &explodeNode)
 		if err != nil {
 			return err
 		}
-		matchingNodes = context.MatchingNodes
 	}
 
 	bufferedWriter := bufio.NewWriter(p.writer)

pkg/yqlib/printer_test.go

@@ -3,7 +3,6 @@ package yqlib
 import (
 	"bufio"
 	"bytes"
-	"container/list"
 	"strings"
 	"testing"
 
@@ -17,12 +16,6 @@ a: apple
 a: coconut
 `
 
-func nodeToList(candidate *CandidateNode) *list.List {
-	elMap := list.New()
-	elMap.PushBack(candidate)
-	return elMap
-}
-
 func TestPrinterMultipleDocsInSequence(t *testing.T) {
 	var output bytes.Buffer
 	var writer = bufio.NewWriter(&output)
@@ -34,13 +27,13 @@ func TestPrinterMultipleDocsInSequence(t *testing.T) {
 	}
 
 	el := inputs.Front()
-	sample1 := nodeToList(el.Value.(*CandidateNode))
+	sample1 := nodeToMap(el.Value.(*CandidateNode))
 
 	el = el.Next()
-	sample2 := nodeToList(el.Value.(*CandidateNode))
+	sample2 := nodeToMap(el.Value.(*CandidateNode))
 
 	el = el.Next()
-	sample3 := nodeToList(el.Value.(*CandidateNode))
+	sample3 := nodeToMap(el.Value.(*CandidateNode))
 
 	err = printer.PrintResults(sample1)
 	if err != nil {
@@ -75,19 +68,19 @@ func TestPrinterMultipleFilesInSequence(t *testing.T) {
 	elNode := el.Value.(*CandidateNode)
 	elNode.Document = 0
 	elNode.FileIndex = 0
-	sample1 := nodeToList(elNode)
+	sample1 := nodeToMap(elNode)
 
 	el = el.Next()
 	elNode = el.Value.(*CandidateNode)
 	elNode.Document = 0
 	elNode.FileIndex = 1
-	sample2 := nodeToList(elNode)
+	sample2 := nodeToMap(elNode)
 
 	el = el.Next()
 	elNode = el.Value.(*CandidateNode)
 	elNode.Document = 0
 	elNode.FileIndex = 2
-	sample3 := nodeToList(elNode)
+	sample3 := nodeToMap(elNode)
 
 	err = printer.PrintResults(sample1)
 	if err != nil {

pkg/yqlib/stream_evaluator.go

@@ -41,11 +41,11 @@ func (s *streamEvaluator) EvaluateNew(expression string, printer Printer) error
 	inputList := list.New()
 	inputList.PushBack(candidateNode)
 
-	result, errorParsing := s.treeNavigator.GetMatchingNodes(Context{MatchingNodes: inputList}, node)
+	matches, errorParsing := s.treeNavigator.GetMatchingNodes(inputList, node)
 	if errorParsing != nil {
 		return errorParsing
 	}
-	return printer.PrintResults(result.MatchingNodes)
+	return printer.PrintResults(matches)
 }
 
 func (s *streamEvaluator) EvaluateFiles(expression string, filenames []string, printer Printer) error {
@@ -97,11 +97,11 @@ func (s *streamEvaluator) Evaluate(filename string, reader io.Reader, node *Expr
 		inputList := list.New()
 		inputList.PushBack(candidateNode)
 
-		result, errorParsing := s.treeNavigator.GetMatchingNodes(Context{MatchingNodes: inputList}, node)
+		matches, errorParsing := s.treeNavigator.GetMatchingNodes(inputList, node)
 		if errorParsing != nil {
 			return errorParsing
 		}
-		err := printer.PrintResults(result.MatchingNodes)
+		err := printer.PrintResults(matches)
 		if err != nil {
 			return err
 		}

pkg/yqlib/utils.go

@@ -40,7 +40,6 @@ func readDocuments(reader io.Reader, filename string, fileIndex int) (*list.List
 			Filename:  filename,
 			Node:      &dataBucket,
 			FileIndex: fileIndex,
-			EvaluateTogether: true,
 		}
 
 		inputList.PushBack(candidateNode)

release_instructions.txt

@@ -2,13 +2,11 @@
 - increment version in snapcraft.yaml
 - increment version in github-action/Dockerfile
 - make sure local build passes
-- commit version update changes
 - tag git with same version number
 - commit vX tag - this will trigger github actions
 - use github actions to publish docker and make github release
 - check github updated yq action in marketplace
 
-
 - snapcraft
   - will auto create a candidate, test it works then promote
   

snap/snapcraft.yaml

@@ -1,5 +1,5 @@
 name: yq
-version: '4.5.1'
+version: '4.4.0'
 summary: A lightweight and portable command-line YAML processor
 description: |
   The aim of the project is to be the jq or sed of yaml files.