yq/pkg/yqlib/operator_strings.go
Mike Farah 4696d11bbc wip
2023-04-08 21:42:46 +10:00

445 lines
13 KiB
Go

package yqlib
import (
"container/list"
"fmt"
"regexp"
"strings"
)
type changeCasePrefs struct {
ToUpperCase bool
}
func trimSpaceOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
results := list.New()
for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
candidate := el.Value.(*CandidateNode)
node := candidate.unwrapDocument()
if node.guessTagFromCustomType() != "!!str" {
return Context{}, fmt.Errorf("cannot trim %v, can only operate on strings. ", node.Tag)
}
newStringNode := candidate.CreateReplacement(ScalarNode, node.Tag, strings.TrimSpace(node.Value))
newStringNode.Style = node.Style
results.PushBack(newStringNode)
}
return context.ChildContext(results), nil
}
func changeCaseOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
results := list.New()
prefs := expressionNode.Operation.Preferences.(changeCasePrefs)
for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
candidate := el.Value.(*CandidateNode)
node := candidate.unwrapDocument()
if node.guessTagFromCustomType() != "!!str" {
return Context{}, fmt.Errorf("cannot change case with %v, can only operate on strings. ", node.Tag)
}
value := ""
if prefs.ToUpperCase {
value = strings.ToUpper(node.Value)
} else {
value = strings.ToLower(node.Value)
}
newStringNode := candidate.CreateReplacement(ScalarNode, node.Tag, value)
newStringNode.Style = node.Style
results.PushBack(newStringNode)
}
return context.ChildContext(results), nil
}
func getSubstituteParameters(d *dataTreeNavigator, block *ExpressionNode, context Context) (string, string, error) {
regEx := ""
replacementText := ""
regExNodes, err := d.GetMatchingNodes(context.ReadOnlyClone(), block.LHS)
if err != nil {
return "", "", err
}
if regExNodes.MatchingNodes.Front() != nil {
regEx = regExNodes.MatchingNodes.Front().Value.(*CandidateNode).Value
}
log.Debug("regEx %v", regEx)
replacementNodes, err := d.GetMatchingNodes(context, block.RHS)
if err != nil {
return "", "", err
}
if replacementNodes.MatchingNodes.Front() != nil {
replacementText = replacementNodes.MatchingNodes.Front().Value.(*CandidateNode).Value
}
return regEx, replacementText, nil
}
func substitute(original string, regex *regexp.Regexp, replacement string) (Kind, string, string) {
replacedString := regex.ReplaceAllString(original, replacement)
return ScalarNode, "!!str", replacedString
}
func substituteStringOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
//rhs block operator
//lhs of block = regex
//rhs of block = replacement expression
block := expressionNode.RHS
regExStr, replacementText, err := getSubstituteParameters(d, block, context)
if err != nil {
return Context{}, err
}
regEx, err := regexp.Compile(regExStr)
if err != nil {
return Context{}, err
}
var results = list.New()
for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
candidate := el.Value.(*CandidateNode)
node := candidate.unwrapDocument()
if node.guessTagFromCustomType() != "!!str" {
return Context{}, fmt.Errorf("cannot substitute with %v, can only substitute strings. Hint: Most often you'll want to use '|=' over '=' for this operation", node.Tag)
}
result := candidate.CreateReplacement(substitute(node.Value, regEx, replacementText))
results.PushBack(result)
}
return context.ChildContext(results), nil
}
func addMatch(original []*CandidateNode, match string, offset int, name string) []*CandidateNode {
newContent := append(original,
createScalarNode("string", "string"))
if offset < 0 {
// offset of -1 means there was no match, force a null value like jq
newContent = append(newContent,
createScalarNode(nil, "null"),
)
} else {
newContent = append(newContent,
createScalarNode(match, match),
)
}
newContent = append(newContent,
createScalarNode("offset", "offset"),
createScalarNode(offset, fmt.Sprintf("%v", offset)),
createScalarNode("length", "length"),
createScalarNode(len(match), fmt.Sprintf("%v", len(match))))
if name != "" {
newContent = append(newContent,
createScalarNode("name", "name"),
createScalarNode(name, name),
)
}
return newContent
}
type matchPreferences struct {
Global bool
}
func getMatches(matchPrefs matchPreferences, regEx *regexp.Regexp, value string) ([][]string, [][]int) {
var allMatches [][]string
var allIndices [][]int
if matchPrefs.Global {
allMatches = regEx.FindAllStringSubmatch(value, -1)
allIndices = regEx.FindAllStringSubmatchIndex(value, -1)
} else {
allMatches = [][]string{regEx.FindStringSubmatch(value)}
allIndices = [][]int{regEx.FindStringSubmatchIndex(value)}
}
log.Debug("allMatches, %v", allMatches)
return allMatches, allIndices
}
func match(matchPrefs matchPreferences, regEx *regexp.Regexp, candidate *CandidateNode, value string, results *list.List) {
subNames := regEx.SubexpNames()
allMatches, allIndices := getMatches(matchPrefs, regEx, value)
// if all matches just has an empty array in it,
// then nothing matched
if len(allMatches) > 0 && len(allMatches[0]) == 0 {
return
}
for i, matches := range allMatches {
capturesListNode := &CandidateNode{Kind: SequenceNode}
match, submatches := matches[0], matches[1:]
for j, submatch := range submatches {
captureNode := &CandidateNode{Kind: MappingNode}
captureNode.Content = addMatch(captureNode.Content, submatch, allIndices[i][2+j*2], subNames[j+1])
capturesListNode.Content = append(capturesListNode.Content, captureNode)
}
node := candidate.CreateReplacement(MappingNode, "!!map", "")
node.Content = addMatch(node.Content, match, allIndices[i][0], "")
node.Content = append(node.Content,
createScalarNode("captures", "captures"),
capturesListNode,
)
results.PushBack(node)
}
}
func capture(matchPrefs matchPreferences, regEx *regexp.Regexp, candidate *CandidateNode, value string, results *list.List) {
subNames := regEx.SubexpNames()
allMatches, allIndices := getMatches(matchPrefs, regEx, value)
// if all matches just has an empty array in it,
// then nothing matched
if len(allMatches) > 0 && len(allMatches[0]) == 0 {
return
}
for i, matches := range allMatches {
capturesNode := candidate.CreateReplacement(MappingNode, "!!map", "")
_, submatches := matches[0], matches[1:]
for j, submatch := range submatches {
capturesNode.Content = append(capturesNode.Content,
createScalarNode(subNames[j+1], subNames[j+1]))
offset := allIndices[i][2+j*2]
// offset of -1 means there was no match, force a null value like jq
if offset < 0 {
capturesNode.Content = append(capturesNode.Content,
createScalarNode(nil, "null"),
)
} else {
capturesNode.Content = append(capturesNode.Content,
createScalarNode(submatch, submatch),
)
}
}
results.PushBack(capturesNode)
}
}
func extractMatchArguments(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (*regexp.Regexp, matchPreferences, error) {
regExExpNode := expressionNode.RHS
matchPrefs := matchPreferences{}
// we got given parameters e.g. match(exp; params)
if expressionNode.RHS.Operation.OperationType == blockOpType {
block := expressionNode.RHS
regExExpNode = block.LHS
replacementNodes, err := d.GetMatchingNodes(context, block.RHS)
if err != nil {
return nil, matchPrefs, err
}
paramText := ""
if replacementNodes.MatchingNodes.Front() != nil {
paramText = replacementNodes.MatchingNodes.Front().Value.(*CandidateNode).Value
}
if strings.Contains(paramText, "g") {
paramText = strings.ReplaceAll(paramText, "g", "")
matchPrefs.Global = true
}
if strings.Contains(paramText, "i") {
return nil, matchPrefs, fmt.Errorf(`'i' is not a valid option for match. To ignore case, use an expression like match("(?i)cat")`)
}
if len(paramText) > 0 {
return nil, matchPrefs, fmt.Errorf(`Unrecognised match params '%v', please see docs at https://mikefarah.gitbook.io/yq/operators/string-operators`, paramText)
}
}
regExNodes, err := d.GetMatchingNodes(context.ReadOnlyClone(), regExExpNode)
if err != nil {
return nil, matchPrefs, err
}
log.Debug(NodesToString(regExNodes.MatchingNodes))
regExStr := ""
if regExNodes.MatchingNodes.Front() != nil {
regExStr = regExNodes.MatchingNodes.Front().Value.(*CandidateNode).Value
}
log.Debug("regEx %v", regExStr)
regEx, err := regexp.Compile(regExStr)
return regEx, matchPrefs, err
}
func matchOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
regEx, matchPrefs, err := extractMatchArguments(d, context, expressionNode)
if err != nil {
return Context{}, err
}
var results = list.New()
for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
candidate := el.Value.(*CandidateNode)
node := candidate.unwrapDocument()
if node.guessTagFromCustomType() != "!!str" {
return Context{}, fmt.Errorf("cannot match with %v, can only match strings. Hint: Most often you'll want to use '|=' over '=' for this operation", node.Tag)
}
match(matchPrefs, regEx, candidate, node.Value, results)
}
return context.ChildContext(results), nil
}
func captureOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
regEx, matchPrefs, err := extractMatchArguments(d, context, expressionNode)
if err != nil {
return Context{}, err
}
var results = list.New()
for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
candidate := el.Value.(*CandidateNode)
node := candidate.unwrapDocument()
if node.guessTagFromCustomType() != "!!str" {
return Context{}, fmt.Errorf("cannot match with %v, can only match strings. Hint: Most often you'll want to use '|=' over '=' for this operation", node.Tag)
}
capture(matchPrefs, regEx, candidate, node.Value, results)
}
return context.ChildContext(results), nil
}
func testOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
regEx, _, err := extractMatchArguments(d, context, expressionNode)
if err != nil {
return Context{}, err
}
var results = list.New()
for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
candidate := el.Value.(*CandidateNode)
node := candidate.unwrapDocument()
if node.guessTagFromCustomType() != "!!str" {
return Context{}, fmt.Errorf("cannot match with %v, can only match strings. Hint: Most often you'll want to use '|=' over '=' for this operation", node.Tag)
}
matches := regEx.FindStringSubmatch(node.Value)
results.PushBack(createBooleanCandidate(candidate, len(matches) > 0))
}
return context.ChildContext(results), nil
}
func joinStringOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
log.Debugf("-- joinStringOperator")
joinStr := ""
rhs, err := d.GetMatchingNodes(context.ReadOnlyClone(), expressionNode.RHS)
if err != nil {
return Context{}, err
}
if rhs.MatchingNodes.Front() != nil {
joinStr = rhs.MatchingNodes.Front().Value.(*CandidateNode).Value
}
var results = list.New()
for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
candidate := el.Value.(*CandidateNode)
node := candidate.unwrapDocument()
if node.Kind != SequenceNode {
return Context{}, fmt.Errorf("cannot join with %v, can only join arrays of scalars", node.Tag)
}
result := candidate.CreateReplacement(join(node.Content, joinStr))
results.PushBack(result)
}
return context.ChildContext(results), nil
}
func join(content []*CandidateNode, joinStr string) (Kind, string, string) {
var stringsToJoin []string
for _, node := range content {
str := node.Value
if node.Tag == "!!null" {
str = ""
}
stringsToJoin = append(stringsToJoin, str)
}
return ScalarNode, "!!str", strings.Join(stringsToJoin, joinStr)
}
func splitStringOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
log.Debugf("-- splitStringOperator")
splitStr := ""
rhs, err := d.GetMatchingNodes(context.ReadOnlyClone(), expressionNode.RHS)
if err != nil {
return Context{}, err
}
if rhs.MatchingNodes.Front() != nil {
splitStr = rhs.MatchingNodes.Front().Value.(*CandidateNode).Value
}
var results = list.New()
for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
candidate := el.Value.(*CandidateNode)
node := candidate.unwrapDocument()
if node.Tag == "!!null" {
continue
}
if node.guessTagFromCustomType() != "!!str" {
return Context{}, fmt.Errorf("Cannot split %v, can only split strings", node.Tag)
}
kind, tag, content := split(node.Value, splitStr)
result := candidate.CreateReplacement(kind, tag, "")
result.Content = content
results.PushBack(result)
}
return context.ChildContext(results), nil
}
func split(value string, spltStr string) (Kind, string, []*CandidateNode) {
var contents []*CandidateNode
if value != "" {
log.Debug("going to spltStr[%v]", spltStr)
var newStrings = strings.Split(value, spltStr)
contents = make([]*CandidateNode, len(newStrings))
for index, str := range newStrings {
contents[index] = &CandidateNode{Kind: ScalarNode, Tag: "!!str", Value: str}
}
}
return SequenceNode, "!!seq", contents
}