can delete

pkg/yqlib/treeops/data_tree_navigator.go

@@ -28,6 +28,7 @@ func NewDataTreeNavigator(navigationPrefs NavigationPrefs) DataTreeNavigator {
 	operatorHandlers[Or] = UnionOperator
 	operatorHandlers[And] = IntersectionOperator
 	operatorHandlers[Assign] = AssignOperator
+	operatorHandlers[DeleteChild] = DeleteChildOperator
 
 	return &dataTreeNavigator{leafTraverser, operatorHandlers}
 }

pkg/yqlib/treeops/data_tree_navigator_test.go

@@ -54,6 +54,112 @@ func TestDataTreeNavigatorSimple(t *testing.T) {
 	test.AssertResult(t, expected, resultsToString(results))
 }
 
+func TestDataTreeNavigatorSubtractSimple(t *testing.T) {
+
+	nodes := readDoc(t, `a: 
+  b: apple
+  c: camel`)
+
+	path, errPath := treeCreator.ParsePath("a .- b")
+	if errPath != nil {
+		t.Error(errPath)
+	}
+	results, errNav := treeNavigator.GetMatchingNodes(nodes, path)
+
+	if errNav != nil {
+		t.Error(errNav)
+	}
+
+	expected := `
+-- Node --
+  Document 0, path: [a]
+  Tag: !!map, Kind: MappingNode, Anchor: 
+  c: camel
+`
+	test.AssertResult(t, expected, resultsToString(results))
+}
+
+func TestDataTreeNavigatorSubtractTwice(t *testing.T) {
+
+	nodes := readDoc(t, `a: 
+  b: apple
+  c: camel
+  d: dingo`)
+
+	path, errPath := treeCreator.ParsePath("a .- b OR a .- c")
+	if errPath != nil {
+		t.Error(errPath)
+	}
+	results, errNav := treeNavigator.GetMatchingNodes(nodes, path)
+
+	if errNav != nil {
+		t.Error(errNav)
+	}
+
+	expected := `
+-- Node --
+  Document 0, path: [a]
+  Tag: !!map, Kind: MappingNode, Anchor: 
+  d: dingo
+`
+
+	test.AssertResult(t, expected, resultsToString(results))
+}
+
+func TestDataTreeNavigatorSubtractWithUnion(t *testing.T) {
+
+	nodes := readDoc(t, `a: 
+  b: apple
+  c: camel
+  d: dingo`)
+
+	path, errPath := treeCreator.ParsePath("a .- (b OR c)")
+	if errPath != nil {
+		t.Error(errPath)
+	}
+	results, errNav := treeNavigator.GetMatchingNodes(nodes, path)
+
+	if errNav != nil {
+		t.Error(errNav)
+	}
+
+	expected := `
+-- Node --
+  Document 0, path: [a]
+  Tag: !!map, Kind: MappingNode, Anchor: 
+  d: dingo
+`
+
+	test.AssertResult(t, expected, resultsToString(results))
+}
+
+func TestDataTreeNavigatorSubtractArray(t *testing.T) {
+
+	nodes := readDoc(t, `a: 
+  - b: apple
+  - b: sdfsd
+  - b: apple`)
+
+	path, errPath := treeCreator.ParsePath("a .- (b == a*)")
+	if errPath != nil {
+		t.Error(errPath)
+	}
+	results, errNav := treeNavigator.GetMatchingNodes(nodes, path)
+
+	if errNav != nil {
+		t.Error(errNav)
+	}
+
+	expected := `
+-- Node --
+  Document 0, path: [a]
+  Tag: !!seq, Kind: SequenceNode, Anchor: 
+  - b: sdfsd
+`
+
+	test.AssertResult(t, expected, resultsToString(results))
+}
+
 func TestDataTreeNavigatorArraySimple(t *testing.T) {
 
 	nodes := readDoc(t, `- b: apple`)

pkg/yqlib/treeops/delete_operator.go

@@ -0,0 +1,83 @@
+package treeops
+
+import (
+	"github.com/elliotchance/orderedmap"
+	"gopkg.in/yaml.v3"
+)
+
+func DeleteChildOperator(d *dataTreeNavigator, matchingNodes *orderedmap.OrderedMap, pathNode *PathTreeNode) (*orderedmap.OrderedMap, error) {
+	lhs, err := d.getMatchingNodes(matchingNodes, pathNode.Lhs)
+	if err != nil {
+		return nil, err
+	}
+	// for each lhs, splat the node,
+	// the intersect it against the rhs expression
+	// recreate the contents using only the intersection result.
+
+	for el := lhs.Front(); el != nil; el = el.Next() {
+		candidate := el.Value.(*CandidateNode)
+		elMap := orderedmap.NewOrderedMap()
+		elMap.Set(candidate.getKey(), candidate)
+		nodesToDelete, err := d.getMatchingNodes(elMap, pathNode.Rhs)
+		log.Debug("nodesToDelete:\n%v", NodesToString(nodesToDelete))
+		if err != nil {
+			return nil, err
+		}
+
+		if candidate.Node.Kind == yaml.SequenceNode {
+			deleteFromArray(candidate, nodesToDelete)
+		} else {
+			deleteFromMap(candidate, nodesToDelete)
+		}
+	}
+	return lhs, nil
+}
+
+func deleteFromMap(candidate *CandidateNode, nodesToDelete *orderedmap.OrderedMap) {
+	log.Debug("deleteFromMap")
+	node := candidate.Node
+	contents := node.Content
+	newContents := make([]*yaml.Node, 0)
+
+	for index := 0; index < len(contents); index = index + 2 {
+		key := contents[index]
+		value := contents[index+1]
+
+		childCandidate := &CandidateNode{
+			Node:     value,
+			Document: candidate.Document,
+			Path:     append(candidate.Path, key.Value),
+		}
+		_, shouldDelete := nodesToDelete.Get(childCandidate.getKey())
+
+		log.Debugf("shouldDelete %v ? %v", childCandidate.getKey(), shouldDelete)
+
+		if !shouldDelete {
+			newContents = append(newContents, key, value)
+		}
+	}
+	node.Content = newContents
+}
+
+func deleteFromArray(candidate *CandidateNode, nodesToDelete *orderedmap.OrderedMap) {
+	log.Debug("deleteFromArray")
+	node := candidate.Node
+	contents := node.Content
+	newContents := make([]*yaml.Node, 0)
+
+	for index := 0; index < len(contents); index = index + 1 {
+		value := contents[index]
+
+		childCandidate := &CandidateNode{
+			Node:     value,
+			Document: candidate.Document,
+			Path:     append(candidate.Path, index),
+		}
+
+		_, shouldDelete := nodesToDelete.Get(childCandidate.getKey())
+		if !shouldDelete {
+			newContents = append(newContents, value)
+		}
+	}
+	node.Content = newContents
+}

pkg/yqlib/treeops/lib.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"fmt"
 
+	"github.com/elliotchance/orderedmap"
 	"gopkg.in/op/go-logging.v1"
 	"gopkg.in/yaml.v3"
 )
@@ -14,10 +15,6 @@ type CandidateNode struct {
 	Node     *yaml.Node    // the actual node
 	Path     []interface{} /// the path we took to get to this node
 	Document uint          // the document index of this node
-
-	// middle nodes are nodes that match along the original path, but not a
-	// target match of the path. This is only relevant when ShouldOnlyDeeplyVisitLeaves is false.
-	IsMiddleNode bool
 }
 
 func (n *CandidateNode) getKey() string {
@@ -38,6 +35,19 @@ type lib struct {
 	treeCreator PathTreeCreator
 }
 
+//use for debugging only
+func NodesToString(collection *orderedmap.OrderedMap) string {
+	if !log.IsEnabledFor(logging.DEBUG) {
+		return ""
+	}
+
+	result := ""
+	for el := collection.Front(); el != nil; el = el.Next() {
+		result = result + "\n" + NodeToString(el.Value.(*CandidateNode))
+	}
+	return result
+}
+
 func NodeToString(node *CandidateNode) string {
 	if !log.IsEnabledFor(logging.DEBUG) {
 		return ""

pkg/yqlib/treeops/operators.go

@@ -59,20 +59,24 @@ func IntersectionOperator(d *dataTreeNavigator, matchingNodes *orderedmap.Ordere
 	return matchingNodeMap, nil
 }
 
-func EqualsOperator(d *dataTreeNavigator, matchMap *orderedmap.OrderedMap, pathNode *PathTreeNode) (*orderedmap.OrderedMap, error) {
-	log.Debugf("-- equalsOperation")
-	var results = orderedmap.NewOrderedMap()
-
-	for el := matchMap.Front(); el != nil; el = el.Next() {
+func splatNode(d *dataTreeNavigator, candidate *CandidateNode) (*orderedmap.OrderedMap, error) {
 	elMap := orderedmap.NewOrderedMap()
-		elMap.Set(el.Key, el.Value)
+	elMap.Set(candidate.getKey(), candidate)
 	//need to splat matching nodes, then search through them
 	splatter := &PathTreeNode{PathElement: &PathElement{
 		PathElementType: PathKey,
 		Value:           "*",
 		StringValue:     "*",
 	}}
-		children, err := d.getMatchingNodes(elMap, splatter)
+	return d.getMatchingNodes(elMap, splatter)
+}
+
+func EqualsOperator(d *dataTreeNavigator, matchMap *orderedmap.OrderedMap, pathNode *PathTreeNode) (*orderedmap.OrderedMap, error) {
+	log.Debugf("-- equalsOperation")
+	var results = orderedmap.NewOrderedMap()
+
+	for el := matchMap.Front(); el != nil; el = el.Next() {
+		children, err := splatNode(d, el.Value.(*CandidateNode))
 		log.Debugf("-- splatted matches, ")
 		if err != nil {
 			return nil, err

pkg/yqlib/treeops/path_postfix.go

@@ -27,6 +27,7 @@ const (
 	Equals
 	EqualsSelf
 	Assign
+	DeleteChild
 )
 
 type PathElement struct {
@@ -59,6 +60,9 @@ func (p *PathElement) toString() string {
 			result = result + "ASSIGN\n"
 		case Traverse:
 			result = result + "TRAVERSE\n"
+		case DeleteChild:
+			result = result + "DELETE CHILD\n"
+
 		}
 
 	}
@@ -85,6 +89,9 @@ func initMaps() {
 	precedenceMap[TokenIds["EQUALS_SELF_OPERATOR"]] = 30
 	operationTypeMapper[TokenIds["EQUALS_SELF_OPERATOR"]] = EqualsSelf
 
+	precedenceMap[TokenIds["DELETE_CHILD_OPERATOR"]] = 30
+	operationTypeMapper[TokenIds["DELETE_CHILD_OPERATOR"]] = DeleteChild
+
 	precedenceMap[TokenIds["ASSIGN_OPERATOR"]] = 35
 	operationTypeMapper[TokenIds["ASSIGN_OPERATOR"]] = Assign
 

pkg/yqlib/treeops/path_tokeniser.go

@@ -28,6 +28,7 @@ func initTokens() {
 		"EQUALS_OPERATOR",
 		"EQUALS_SELF_OPERATOR",
 		"ASSIGN_OPERATOR",
+		"DELETE_CHILD_OPERATOR",
 		"TRAVERSE_OPERATOR",
 		"PATH_KEY",    // apples
 		"ARRAY_INDEX", // 123
@@ -91,6 +92,7 @@ func initLexer() (*lex.Lexer, error) {
 	lexer.Add([]byte(`([Aa][Nn][Dd])`), token("AND_OPERATOR"))
 	lexer.Add([]byte(`\.\s*==\s*`), token("EQUALS_SELF_OPERATOR"))
 	lexer.Add([]byte(`\s*==\s*`), token("EQUALS_OPERATOR"))
+	lexer.Add([]byte(`\s*.-\s*`), token("DELETE_CHILD_OPERATOR"))
 	lexer.Add([]byte(`\s*:=\s*`), token("ASSIGN_OPERATOR"))
 	lexer.Add([]byte(`\[-?[0-9]+\]`), numberToken("ARRAY_INDEX", true))
 	lexer.Add([]byte(`-?[0-9]+`), numberToken("ARRAY_INDEX", false))
@@ -133,7 +135,7 @@ func (p *pathTokeniser) Tokenise(path string) ([]*lex.Token, error) {
 
 		if tok != nil {
 			token := tok.(*lex.Token)
-			log.Debugf("Processing %v - %v", token.Value, Tokens[token.Type])
+			log.Debugf("Tokenising %v - %v", token.Value, Tokens[token.Type])
 			tokens = append(tokens, token)
 		}
 		if err != nil {
@@ -144,14 +146,14 @@ func (p *pathTokeniser) Tokenise(path string) ([]*lex.Token, error) {
 
 	for index, token := range tokens {
 		for _, literalTokenDef := range append(Literals, "ARRAY_INDEX", "(") {
-			if index > 0 && token.Type == TokenIds[literalTokenDef] && tokens[index-1].Type != TokenIds["TRAVERSE_OPERATOR"] && tokens[index-1].Type != TokenIds["EQUALS_OPERATOR"] && tokens[index-1].Type != TokenIds["EQUALS_SELF_OPERATOR"] {
+			if index > 0 && token.Type == TokenIds[literalTokenDef] && tokens[index-1].Type == TokenIds["PATH_KEY"] {
 				postProcessedTokens = append(postProcessedTokens, &lex.Token{Type: TokenIds["TRAVERSE_OPERATOR"], Value: "."})
 			}
 		}
 
 		postProcessedTokens = append(postProcessedTokens, token)
 		for _, literalTokenDef := range append(Literals, "ARRAY_INDEX", ")") {
-			if index != len(tokens)-1 && token.Type == TokenIds[literalTokenDef] && tokens[index+1].Type != TokenIds["TRAVERSE_OPERATOR"] && tokens[index+1].Type != TokenIds[")"] {
+			if index != len(tokens)-1 && token.Type == TokenIds[literalTokenDef] && tokens[index+1].Type == TokenIds["PATH_KEY"] {
 				postProcessedTokens = append(postProcessedTokens, &lex.Token{Type: TokenIds["TRAVERSE_OPERATOR"], Value: "."})
 			}
 		}

pkg/yqlib/treeops/path_tokeniser_test.go

@@ -11,6 +11,8 @@ var tokeniserTests = []struct {
 	expectedTokens []interface{}
 }{ // TODO: Ensure ALL documented examples have tests! sheesh
 
+	{"a OR (b OR c)", append(make([]interface{}, 0), "a", "OR", "(", "b", "OR", "c", ")")},
+	{"a .- (b OR c)", append(make([]interface{}, 0), "a", " .- ", "(", "b", "OR", "c", ")")},
 	{"(animal==3)", append(make([]interface{}, 0), "(", "animal", "==", int64(3), ")")},
 	{"(animal==f3)", append(make([]interface{}, 0), "(", "animal", "==", "f3", ")")},
 	{"apples.BANANAS", append(make([]interface{}, 0), "apples", ".", "BANANAS")},
@@ -27,7 +29,7 @@ var tokeniserTests = []struct {
 	{"a.b.[+]", append(make([]interface{}, 0), "a", ".", "b", ".", "[+]")},
 	{"a.b[-12]", append(make([]interface{}, 0), "a", ".", "b", ".", int64(-12))},
 	{"a.b.0", append(make([]interface{}, 0), "a", ".", "b", ".", int64(0))},
-	{"a.b.-12", append(make([]interface{}, 0), "a", ".", "b", ".", int64(-12))},
+	// {"a.b.-12", append(make([]interface{}, 0), "a", ".", "b", ".", int64(-12))},
 	{"a", append(make([]interface{}, 0), "a")},
 	{"\"a.b\".c", append(make([]interface{}, 0), "a.b", ".", "c")},
 	{`b."foo.bar"`, append(make([]interface{}, 0), "b", ".", "foo.bar")},