2025-10-15 10:12:44 +03:00

1109 lines
44 KiB
Go

package estransforms
import (
"strconv"
"efprojects.com/kitten-ipc/kitcom/internal/tsgo/ast"
"efprojects.com/kitten-ipc/kitcom/internal/tsgo/core"
"efprojects.com/kitten-ipc/kitcom/internal/tsgo/debug"
"efprojects.com/kitten-ipc/kitcom/internal/tsgo/printer"
"efprojects.com/kitten-ipc/kitcom/internal/tsgo/transformers"
)
type pendingDecl struct {
pendingExpressions []*ast.Node
name *ast.Node
value *ast.Node
location core.TextRange
original *ast.Node
}
type flattenLevel int
const (
flattenLevelAll flattenLevel = iota
flattenLevelObjectRest
)
type flattenContext struct {
level flattenLevel
currentExpressions []*ast.Node
currentDeclarations []pendingDecl
hasTransformedPriorElement bool
emitBindingOrAssignment func(t *objectRestSpreadTransformer, target *ast.Node, value *ast.Node, location core.TextRange, original *ast.Node)
createArrayBindingOrAssignmentPattern func(t *objectRestSpreadTransformer, elements []*ast.Node) *ast.Node
createObjectBindingOrAssignmentPattern func(t *objectRestSpreadTransformer, elements []*ast.Node) *ast.Node
createArrayBindingOrAssignmentElement func(t *objectRestSpreadTransformer, expr *ast.Node) *ast.Node
hoistTempVariables bool
}
type oldFlattenContext flattenContext
type objectRestSpreadTransformer struct {
transformers.Transformer
compilerOptions *core.CompilerOptions
inExportedVariableStatement bool
ctx flattenContext
parametersWithPrecedingObjectRestOrSpread map[*ast.Node]struct{}
}
func (ch *objectRestSpreadTransformer) enterFlattenContext(
level flattenLevel,
emitBindingOrAssignment func(t *objectRestSpreadTransformer, target *ast.Node, value *ast.Node, location core.TextRange, original *ast.Node),
createArrayBindingOrAssignmentPattern func(t *objectRestSpreadTransformer, elements []*ast.Node) *ast.Node,
createObjectBindingOrAssignmentPattern func(t *objectRestSpreadTransformer, elements []*ast.Node) *ast.Node,
createArrayBindingOrAssignmentElement func(t *objectRestSpreadTransformer, expr *ast.Node) *ast.Node,
hoistTempVariables bool,
) oldFlattenContext {
old := ch.ctx
ch.ctx = flattenContext{
level: level,
emitBindingOrAssignment: emitBindingOrAssignment,
createArrayBindingOrAssignmentPattern: createArrayBindingOrAssignmentPattern,
createObjectBindingOrAssignmentPattern: createObjectBindingOrAssignmentPattern,
createArrayBindingOrAssignmentElement: createArrayBindingOrAssignmentElement,
hoistTempVariables: hoistTempVariables,
}
return oldFlattenContext(old)
}
func (ch *objectRestSpreadTransformer) exitFlattenContext(old oldFlattenContext) {
ch.ctx = flattenContext(old)
}
func (ch *objectRestSpreadTransformer) visit(node *ast.Node) *ast.Node {
if node.SubtreeFacts()&ast.SubtreeContainsESObjectRestOrSpread == 0 && ch.parametersWithPrecedingObjectRestOrSpread == nil {
return node
}
switch node.Kind {
case ast.KindSourceFile:
return ch.visitSourceFile(node.AsSourceFile())
case ast.KindObjectLiteralExpression:
return ch.visitObjectLiteralExpression(node.AsObjectLiteralExpression())
case ast.KindBinaryExpression:
return ch.visitBinaryExpression(node.AsBinaryExpression())
case ast.KindForOfStatement:
return ch.visitForOftatement(node.AsForInOrOfStatement())
case ast.KindVariableStatement:
return ch.visitVariableStatement(node.AsVariableStatement())
case ast.KindVariableDeclaration:
return ch.visitVariableDeclaration(node.AsVariableDeclaration())
case ast.KindCatchClause:
return ch.visitCatchClause(node.AsCatchClause())
case ast.KindParameter:
return ch.visitParameter(node.AsParameterDeclaration())
case ast.KindConstructor:
return ch.visitContructorDeclaration(node.AsConstructorDeclaration())
case ast.KindGetAccessor:
return ch.visitGetAccessorDeclaration(node.AsGetAccessorDeclaration())
case ast.KindSetAccessor:
return ch.visitSetAccessorDeclaration(node.AsSetAccessorDeclaration())
case ast.KindMethodDeclaration:
return ch.visitMethodDeclaration(node.AsMethodDeclaration())
case ast.KindFunctionDeclaration:
return ch.visitFunctionDeclaration(node.AsFunctionDeclaration())
case ast.KindArrowFunction:
return ch.visitArrowFunction(node.AsArrowFunction())
case ast.KindFunctionExpression:
return ch.visitFunctionExpression(node.AsFunctionExpression())
default:
return ch.Visitor().VisitEachChild(node)
}
}
func (ch *objectRestSpreadTransformer) visitSourceFile(node *ast.SourceFile) *ast.Node {
visited := ch.Visitor().VisitEachChild(node.AsNode())
ch.EmitContext().AddEmitHelper(visited.AsNode(), ch.EmitContext().ReadEmitHelpers()...)
return visited
}
func (ch *objectRestSpreadTransformer) visitParameter(node *ast.ParameterDeclaration) *ast.Node {
if ch.parametersWithPrecedingObjectRestOrSpread != nil {
if _, ok := ch.parametersWithPrecedingObjectRestOrSpread[node.AsNode()]; ok {
name := node.Name()
if ast.IsBindingPattern(name) {
name = ch.Factory().NewGeneratedNameForNode(node.AsNode())
}
return ch.Factory().UpdateParameterDeclaration(
node,
nil,
node.DotDotDotToken,
name,
nil,
nil,
nil,
)
}
}
if node.SubtreeFacts()&ast.SubtreeContainsObjectRestOrSpread != 0 {
// Binding patterns are converted into a generated name and are
// evaluated inside the function body.
return ch.Factory().UpdateParameterDeclaration(
node,
nil,
node.DotDotDotToken,
ch.Factory().NewGeneratedNameForNode(node.AsNode()),
nil,
nil,
ch.Visitor().VisitNode(node.Initializer),
)
}
return ch.Visitor().VisitEachChild(node.AsNode())
}
func (ch *objectRestSpreadTransformer) collectParametersWithPrecedingObjectRestOrSpread(node *ast.Node) map[*ast.Node]struct{} {
var result map[*ast.Node]struct{}
for _, parameter := range node.Parameters() {
if result != nil {
result[parameter] = struct{}{}
} else if parameter.SubtreeFacts()&ast.SubtreeContainsObjectRestOrSpread != 0 {
result = make(map[*ast.Node]struct{})
}
}
return result
}
type oldParamScope map[*ast.Node]struct{}
func (ch *objectRestSpreadTransformer) enterParameterListContext(node *ast.Node) oldParamScope {
old := ch.parametersWithPrecedingObjectRestOrSpread
ch.parametersWithPrecedingObjectRestOrSpread = ch.collectParametersWithPrecedingObjectRestOrSpread(node)
return oldParamScope(old)
}
func (ch *objectRestSpreadTransformer) exitParameterListContext(scope oldParamScope) {
ch.parametersWithPrecedingObjectRestOrSpread = map[*ast.Node]struct{}(scope)
}
func (ch *objectRestSpreadTransformer) visitContructorDeclaration(node *ast.ConstructorDeclaration) *ast.Node {
old := ch.enterParameterListContext(node.AsNode())
defer ch.exitParameterListContext(old)
return ch.Factory().UpdateConstructorDeclaration(
node,
node.Modifiers(),
nil,
ch.Visitor().VisitNodes(node.Parameters),
nil,
nil,
ch.transformFunctionBody(node.AsNode()),
)
}
func (ch *objectRestSpreadTransformer) visitGetAccessorDeclaration(node *ast.GetAccessorDeclaration) *ast.Node {
old := ch.enterParameterListContext(node.AsNode())
defer ch.exitParameterListContext(old)
return ch.Factory().UpdateGetAccessorDeclaration(
node,
node.Modifiers(),
ch.Visitor().VisitNode(node.Name()),
nil,
ch.Visitor().VisitNodes(node.Parameters),
nil,
nil,
ch.transformFunctionBody(node.AsNode()),
)
}
func (ch *objectRestSpreadTransformer) visitSetAccessorDeclaration(node *ast.SetAccessorDeclaration) *ast.Node {
old := ch.enterParameterListContext(node.AsNode())
defer ch.exitParameterListContext(old)
return ch.Factory().UpdateSetAccessorDeclaration(
node,
node.Modifiers(),
ch.Visitor().VisitNode(node.Name()),
nil,
ch.Visitor().VisitNodes(node.Parameters),
nil,
nil,
ch.transformFunctionBody(node.AsNode()),
)
}
func (ch *objectRestSpreadTransformer) visitMethodDeclaration(node *ast.MethodDeclaration) *ast.Node {
old := ch.enterParameterListContext(node.AsNode())
defer ch.exitParameterListContext(old)
return ch.Factory().UpdateMethodDeclaration(
node,
node.Modifiers(),
node.AsteriskToken,
ch.Visitor().VisitNode(node.Name()),
node.PostfixToken,
nil,
ch.Visitor().VisitNodes(node.Parameters),
nil,
nil,
ch.transformFunctionBody(node.AsNode()),
)
}
func (ch *objectRestSpreadTransformer) visitFunctionDeclaration(node *ast.FunctionDeclaration) *ast.Node {
old := ch.enterParameterListContext(node.AsNode())
defer ch.exitParameterListContext(old)
return ch.Factory().UpdateFunctionDeclaration(
node,
node.Modifiers(),
node.AsteriskToken,
ch.Visitor().VisitNode(node.Name()),
nil,
ch.Visitor().VisitNodes(node.Parameters),
nil,
nil,
ch.transformFunctionBody(node.AsNode()),
)
}
func (ch *objectRestSpreadTransformer) visitArrowFunction(node *ast.ArrowFunction) *ast.Node {
old := ch.enterParameterListContext(node.AsNode())
defer ch.exitParameterListContext(old)
return ch.Factory().UpdateArrowFunction(
node,
node.Modifiers(),
nil,
ch.Visitor().VisitNodes(node.Parameters),
nil,
nil,
node.EqualsGreaterThanToken,
ch.transformFunctionBody(node.AsNode()),
)
}
func (ch *objectRestSpreadTransformer) visitFunctionExpression(node *ast.FunctionExpression) *ast.Node {
old := ch.enterParameterListContext(node.AsNode())
defer ch.exitParameterListContext(old)
return ch.Factory().UpdateFunctionExpression(
node,
node.Modifiers(),
node.AsteriskToken,
ch.Visitor().VisitNode(node.Name()),
nil,
ch.Visitor().VisitNodes(node.Parameters),
nil,
nil,
ch.transformFunctionBody(node.AsNode()),
)
}
func (ch *objectRestSpreadTransformer) transformFunctionBody(node *ast.Node) *ast.Node {
ch.EmitContext().StartVariableEnvironment()
body := ch.Visitor().VisitNode(node.Body())
extras := ch.EmitContext().EndVariableEnvironment()
ch.EmitContext().StartVariableEnvironment()
newStatements := ch.collectObjectRestAssignments(node)
extras = ch.EmitContext().EndAndMergeVariableEnvironment(extras)
if len(newStatements) == 0 && len(extras) == 0 {
return body
}
if body == nil {
body = ch.Factory().NewBlock(ch.Factory().NewNodeList([]*ast.Node{}), true)
}
var prefix []*ast.Node
var suffix []*ast.Node
if ast.IsBlock(body) {
custom := false
for i, statement := range body.AsBlock().Statements.Nodes {
if !custom && ast.IsPrologueDirective(statement) {
prefix = append(prefix, statement)
} else if ch.EmitContext().EmitFlags(statement)&printer.EFCustomPrologue != 0 {
custom = true
prefix = append(prefix, statement)
} else {
suffix = body.AsBlock().Statements.Nodes[i:]
break
}
}
} else {
ret := ch.Factory().NewReturnStatement(body)
ret.Loc = body.Loc
list := ch.Factory().NewNodeList([]*ast.Node{})
list.Loc = body.Loc
body = ch.Factory().NewBlock(list, true)
suffix = append(suffix, ret)
}
newStatementList := ch.Factory().NewNodeList(append(append(append(prefix, extras...), newStatements...), suffix...))
newStatementList.Loc = body.AsBlock().Statements.Loc
return ch.Factory().UpdateBlock(body.AsBlock(), newStatementList)
}
func (ch *objectRestSpreadTransformer) collectObjectRestAssignments(node *ast.Node) []*ast.Node {
containsPrecedingObjectRestOrSpread := false
var results []*ast.Node
for _, parameter := range node.Parameters() {
if containsPrecedingObjectRestOrSpread {
if ast.IsBindingPattern(parameter.Name()) {
// In cases where a binding pattern is simply '[]' or '{}',
// we usually don't want to emit a var declaration; however, in the presence
// of an initializer, we must emit that expression to preserve side effects.
if len(parameter.Name().AsBindingPattern().Elements.Nodes) > 0 {
declarations := ch.flattenDestructuringBinding(flattenLevelAll, parameter, ch.Factory().NewGeneratedNameForNode(parameter), false, false)
if declarations != nil {
declarationList := ch.Factory().NewVariableDeclarationList(ast.NodeFlagsNone, ch.Factory().NewNodeList([]*ast.Node{}))
decls := []*ast.Node{declarations}
if declarations.Kind == ast.KindSyntaxList {
decls = declarations.AsSyntaxList().Children
}
declarationList.AsVariableDeclarationList().Declarations.Nodes = append(declarationList.AsVariableDeclarationList().Declarations.Nodes, decls...)
statement := ch.Factory().NewVariableStatement(nil, declarationList)
ch.EmitContext().AddEmitFlags(statement, printer.EFCustomPrologue)
results = append(results, statement)
}
} else if parameter.Initializer() != nil {
name := ch.Factory().NewGeneratedNameForNode(parameter)
initializer := ch.Visitor().VisitNode(parameter.Initializer())
assignment := ch.Factory().NewAssignmentExpression(name, initializer)
statement := ch.Factory().NewExpressionStatement(assignment)
ch.EmitContext().AddEmitFlags(statement, printer.EFCustomPrologue)
results = append(results, statement)
}
} else if parameter.Initializer() != nil {
// Converts a parameter initializer into a function body statement, i.e.:
//
// function f(x = 1) { }
//
// becomes
//
// function f(x) {
// if (typeof x === "undefined") { x = 1; }
// }
name := parameter.Name().Clone(ch.Factory())
name.Loc = parameter.Name().Loc
ch.EmitContext().AddEmitFlags(name, printer.EFNoSourceMap)
initializer := ch.Visitor().VisitNode(parameter.Initializer())
ch.EmitContext().AddEmitFlags(initializer, printer.EFNoSourceMap|printer.EFNoComments)
assignment := ch.Factory().NewAssignmentExpression(name, initializer)
assignment.Loc = parameter.Loc
ch.EmitContext().AddEmitFlags(assignment, printer.EFNoComments)
block := ch.Factory().NewBlock(ch.Factory().NewNodeList([]*ast.Node{ch.Factory().NewExpressionStatement(assignment)}), false)
block.Loc = parameter.Loc
ch.EmitContext().AddEmitFlags(block, printer.EFSingleLine|printer.EFNoTrailingSourceMap|printer.EFNoTokenSourceMaps|printer.EFNoComments)
typeCheck := ch.Factory().NewTypeCheck(name.Clone(ch.Factory()), "undefined")
statement := ch.Factory().NewIfStatement(typeCheck, block, nil)
statement.Loc = parameter.Loc
ch.EmitContext().AddEmitFlags(statement, printer.EFNoTokenSourceMaps|printer.EFNoTrailingSourceMap|printer.EFCustomPrologue|printer.EFNoComments|printer.EFStartOnNewLine)
results = append(results, statement)
}
} else if parameter.SubtreeFacts()&ast.SubtreeContainsObjectRestOrSpread != 0 {
containsPrecedingObjectRestOrSpread = true
declarations := ch.flattenDestructuringBinding(flattenLevelObjectRest, parameter, ch.Factory().NewGeneratedNameForNode(parameter), false, true)
if declarations != nil {
declarationList := ch.Factory().NewVariableDeclarationList(ast.NodeFlagsNone, ch.Factory().NewNodeList([]*ast.Node{}))
decls := []*ast.Node{declarations}
if declarations.Kind == ast.KindSyntaxList {
decls = declarations.AsSyntaxList().Children
}
declarationList.AsVariableDeclarationList().Declarations.Nodes = append(declarationList.AsVariableDeclarationList().Declarations.Nodes, decls...)
statement := ch.Factory().NewVariableStatement(nil, declarationList)
ch.EmitContext().AddEmitFlags(statement, printer.EFCustomPrologue)
results = append(results, statement)
}
}
}
return results
}
func (ch *objectRestSpreadTransformer) visitCatchClause(node *ast.CatchClause) *ast.Node {
if node.VariableDeclaration != nil && ast.IsBindingPattern(node.VariableDeclaration.Name()) && node.VariableDeclaration.Name().SubtreeFacts()&ast.SubtreeContainsObjectRestOrSpread != 0 {
name := ch.Factory().NewGeneratedNameForNode(node.VariableDeclaration.Name())
updatedDecl := ch.Factory().UpdateVariableDeclaration(node.VariableDeclaration.AsVariableDeclaration(), node.VariableDeclaration.Name(), nil, nil, name)
visitedBindings := ch.flattenDestructuringBinding(flattenLevelObjectRest, updatedDecl, nil, false, false)
block := ch.Visitor().VisitNode(node.Block)
if visitedBindings != nil {
var decls []*ast.Node
if visitedBindings.Kind&ast.KindSyntaxList != 0 {
decls = visitedBindings.AsSyntaxList().Children
} else {
decls = []*ast.Node{visitedBindings}
}
newStatement := ch.Factory().NewVariableStatement(nil, ch.Factory().NewVariableDeclarationList(ast.NodeFlagsNone, ch.Factory().NewNodeList(decls)))
statements := []*ast.Node{newStatement}
if block.AsBlock().Statements != nil && len(block.AsBlock().Statements.Nodes) > 0 {
statements = append(statements, block.AsBlock().Statements.Nodes...)
}
statementList := ch.Factory().NewNodeList(statements)
statementList.Loc = block.AsBlock().Statements.Loc
block = ch.Factory().UpdateBlock(block.AsBlock(), statementList)
}
return ch.Factory().UpdateCatchClause(
node,
ch.Factory().UpdateVariableDeclaration(node.VariableDeclaration.AsVariableDeclaration(), name, nil, nil, nil),
block,
)
}
return ch.Visitor().VisitEachChild(node.AsNode())
}
func (ch *objectRestSpreadTransformer) visitVariableStatement(node *ast.VariableStatement) *ast.Node {
if ast.HasSyntacticModifier(node.AsNode(), ast.ModifierFlagsExport) {
oldInExportedVariableStatement := ch.inExportedVariableStatement
ch.inExportedVariableStatement = true
result := ch.Visitor().VisitEachChild(node.AsNode())
ch.inExportedVariableStatement = oldInExportedVariableStatement
return result
}
return ch.Visitor().VisitEachChild(node.AsNode())
}
func (ch *objectRestSpreadTransformer) visitVariableDeclaration(node *ast.VariableDeclaration) *ast.Node {
if ch.inExportedVariableStatement {
ch.inExportedVariableStatement = false
result := ch.visitVariableDeclarationWorker(node, true)
ch.inExportedVariableStatement = true
return result
}
return ch.visitVariableDeclarationWorker(node, false)
}
func (ch *objectRestSpreadTransformer) visitVariableDeclarationWorker(node *ast.VariableDeclaration, exported bool) *ast.Node {
// If we are here it is because the name contains a binding pattern with a rest somewhere in it.
if ast.IsBindingPattern(node.Name()) && node.SubtreeFacts()&ast.SubtreeContainsObjectRestOrSpread != 0 {
return ch.flattenDestructuringBinding(
flattenLevelObjectRest,
node.AsNode(),
nil,
exported,
false,
)
}
return ch.Visitor().VisitEachChild(node.AsNode())
}
func (ch *objectRestSpreadTransformer) flattenDestructuringBinding(level flattenLevel, node *ast.Node, rvalue *ast.Node, hoist bool, skipInitializer bool) *ast.Node {
old := ch.enterFlattenContext(level, (*objectRestSpreadTransformer).emitBinding, (*objectRestSpreadTransformer).createArrayBindingPattern, (*objectRestSpreadTransformer).createObjectBindingPattern, (*objectRestSpreadTransformer).createArrayBindingElement, hoist)
defer ch.exitFlattenContext(old)
if ast.IsVariableDeclaration(node) {
initializer := getInitializerOfBindingOrAssignmentElement(node)
if initializer != nil && (ast.IsIdentifier(initializer) && bindingOrAssignmentElementAssignsToName(node, initializer.AsIdentifier().Text) || bindingOrAssignmentElementContainsNonLiteralComputedName(node)) {
// If the right-hand value of the assignment is also an assignment target then
// we need to cache the right-hand value.
initializer = ch.ensureIdentifier(ch.Visitor().VisitNode(initializer), false, initializer.Loc)
node = ch.Factory().UpdateVariableDeclaration(node.AsVariableDeclaration(), node.Name(), nil, nil, initializer)
}
}
ch.flattenBindingOrAssignmentElement(node, rvalue, node.Loc, skipInitializer)
if len(ch.ctx.currentExpressions) > 0 {
temp := ch.Factory().NewTempVariable()
ch.EmitContext().AddVariableDeclaration(temp)
last := &ch.ctx.currentDeclarations[len(ch.ctx.currentDeclarations)-1]
last.pendingExpressions = append(last.pendingExpressions, ch.Factory().NewAssignmentExpression(temp, last.value))
last.pendingExpressions = append(last.pendingExpressions, ch.ctx.currentExpressions...)
last.value = temp
}
decls := make([]*ast.Node, 0, len(ch.ctx.currentDeclarations))
for _, pending := range ch.ctx.currentDeclarations {
expr := pending.value
if len(pending.pendingExpressions) > 0 {
expr = ch.Factory().InlineExpressions(append(pending.pendingExpressions, pending.value))
}
decl := ch.Factory().NewVariableDeclaration(
pending.name,
nil,
nil,
expr,
)
decl.Loc = pending.location
if pending.original != nil {
ch.EmitContext().SetOriginal(decl, pending.original)
}
decls = append(decls, decl)
}
if len(decls) == 1 {
return decls[0]
}
if len(decls) == 0 {
return nil
}
return ch.Factory().NewSyntaxList(decls)
}
func (ch *objectRestSpreadTransformer) visitForOftatement(node *ast.ForInOrOfStatement) *ast.Node {
if node.Initializer.SubtreeFacts()&ast.SubtreeContainsObjectRestOrSpread != 0 || (ast.IsAssignmentPattern(node.Initializer) && ast.ContainsObjectRestOrSpread(node.Initializer)) {
initializerWithoutParens := ast.SkipParentheses(node.Initializer)
if ast.IsVariableDeclarationList(initializerWithoutParens) || ast.IsAssignmentPattern(initializerWithoutParens) {
var bodyLocation core.TextRange
var statementsLocation core.TextRange
temp := ch.Factory().NewTempVariable()
res := ch.Visitor().VisitNode(ch.createForOfBindingStatement(initializerWithoutParens, temp))
statements := make([]*ast.Node, 0, 1)
if res != nil {
statements = append(statements, res)
}
if ast.IsBlock(node.Statement) {
for _, statement := range node.Statement.AsBlock().Statements.Nodes {
visited := ch.Visitor().VisitEachChild(statement)
if visited != nil {
statements = append(statements, visited)
}
}
bodyLocation = node.Statement.Loc
statementsLocation = node.Statement.AsBlock().Statements.Loc
} else if node.Statement != nil {
statements = append(statements, ch.Visitor().VisitEachChild(node.Statement))
bodyLocation = node.Statement.Loc
statementsLocation = node.Statement.Loc
}
list := ch.Factory().NewVariableDeclarationList(
ast.NodeFlagsLet,
ch.Factory().NewNodeList([]*ast.Node{ch.Factory().NewVariableDeclaration(temp, nil, nil, nil)}),
)
list.Loc = node.Initializer.Loc
expr := ch.Visitor().VisitEachChild(node.Expression)
statementsList := ch.Factory().NewNodeList(statements)
statementsList.Loc = statementsLocation
block := ch.Factory().NewBlock(statementsList, true)
block.Loc = bodyLocation
return ch.Factory().UpdateForInOrOfStatement(
node,
node.AwaitModifier,
list,
expr,
block,
)
}
}
return ch.Visitor().VisitEachChild(node.AsNode())
}
func (ch *objectRestSpreadTransformer) createForOfBindingStatement(node *ast.Node, boundValue *ast.Node) *ast.Node {
if ast.IsVariableDeclarationList(node) {
firstDeclaration := node.AsVariableDeclarationList().Declarations.Nodes[0]
updatedDeclaration := ch.Factory().UpdateVariableDeclaration(
firstDeclaration.AsVariableDeclaration(),
firstDeclaration.Name(),
nil,
nil,
boundValue,
)
statement := ch.Factory().NewVariableStatement(
nil,
ch.Factory().UpdateVariableDeclarationList(
node.AsVariableDeclarationList(),
ch.Factory().NewNodeList([]*ast.Node{updatedDeclaration}),
),
)
statement.Loc = node.Loc
return statement
} else {
updatedExpression := ch.Factory().NewAssignmentExpression(node, boundValue)
updatedExpression.Loc = node.Loc
statement := ch.Factory().NewExpressionStatement(updatedExpression)
statement.Loc = node.Loc
return statement
}
}
func (ch *objectRestSpreadTransformer) visitBinaryExpression(node *ast.BinaryExpression) *ast.Node {
if !(ast.IsDestructuringAssignment(node.AsNode()) && ast.ContainsObjectRestOrSpread(node.Left)) {
return ch.Visitor().VisitEachChild(node.AsNode())
}
return ch.flattenDestructuringAssignment(
node,
)
}
func (ch *objectRestSpreadTransformer) flattenDestructuringAssignment(node *ast.BinaryExpression) *ast.Node {
location := node.Loc
var value *ast.Node
if ast.IsDestructuringAssignment(node.AsNode()) {
value = node.Right
for ast.IsEmptyArrayLiteral(node.Left) || ast.IsEmptyObjectLiteral(node.Left) {
if ast.IsDestructuringAssignment(value) {
node = value.AsBinaryExpression()
location = node.Loc
value = node.Right
} else {
return ch.Visitor().VisitNode(value)
}
}
}
old := ch.enterFlattenContext(flattenLevelObjectRest, (*objectRestSpreadTransformer).emitAssignment, (*objectRestSpreadTransformer).createArrayAssignmentPattern, (*objectRestSpreadTransformer).createObjectAssignmentPattern, (*objectRestSpreadTransformer).createArrayAssignmentElement, true)
defer ch.exitFlattenContext(old)
if value != nil {
value = ch.Visitor().VisitNode(value)
if ast.IsIdentifier(value) && bindingOrAssignmentElementAssignsToName(node.AsNode(), value.AsIdentifier().Text) || bindingOrAssignmentElementContainsNonLiteralComputedName(node.AsNode()) {
// If the right-hand value of the assignment is also an assignment target then
// we need to cache the right-hand value.
value = ch.ensureIdentifier(value, false, location)
} else {
value = ch.ensureIdentifier(value, true, location)
}
if ast.NodeIsSynthesized(node.AsNode()) {
// Generally, the source map location for a destructuring assignment is the root
// expression.
//
// However, if the root expression is synthesized (as in the case
// of the initializer when transforming a ForOfStatement), then the source map
// location should point to the right-hand value of the expression.
location = value.Loc
}
}
ch.flattenBindingOrAssignmentElement(node.AsNode(), value, location, ast.IsDestructuringAssignment(node.AsNode()))
res := ch.Factory().InlineExpressions(ch.ctx.currentExpressions)
if res != nil {
return res
}
return ch.Factory().NewOmittedExpression()
}
func (ch *objectRestSpreadTransformer) flattenBindingOrAssignmentElement(element *ast.Node, value *ast.Node, location core.TextRange, skipInitializer bool) {
bindingTarget := ast.GetTargetOfBindingOrAssignmentElement(element)
if !skipInitializer {
initializer := ch.Visitor().VisitNode(getInitializerOfBindingOrAssignmentElement(element))
if initializer != nil {
// Combine value and initializer
if value != nil {
value = ch.createDefaultValueCheck(value, initializer, location)
// If 'value' is not a simple expression, it could contain side-effecting code that should evaluate before an object or array binding pattern.
if !transformers.IsSimpleCopiableExpression(initializer) && (ast.IsBindingPattern(bindingTarget) || ast.IsAssignmentPattern(bindingTarget)) {
value = ch.ensureIdentifier(value, true, location)
}
} else {
value = initializer
}
} else if value == nil {
// Use 'void 0' in absence of value and initializer
value = ch.Factory().NewVoidZeroExpression()
}
}
if isObjectBindingOrAssignmentPattern(bindingTarget) {
ch.flattenObjectBindingOrAssignmentPattern(element, bindingTarget, value, location)
} else if isArrayBindingOrAssignmentPattern(bindingTarget) {
ch.flattenArrayBindingOrAssignmentPattern(element, bindingTarget, value, location)
} else {
ch.ctx.emitBindingOrAssignment(ch, bindingTarget, value, location, element)
}
}
func (ch *objectRestSpreadTransformer) flattenObjectBindingOrAssignmentPattern(parent *ast.Node, pattern *ast.Node, value *ast.Node, location core.TextRange) {
elements := ast.GetElementsOfBindingOrAssignmentPattern(pattern)
numElements := len(elements)
if numElements != 1 {
// For anything other than a single-element destructuring we need to generate a temporary
// to ensure value is evaluated exactly once. Additionally, if we have zero elements
// we need to emit *something* to ensure that in case a 'var' keyword was already emitted,
// so in that case, we'll intentionally create that temporary.
reuseIdentifierExpressions := !ast.IsDeclarationBindingElement(parent) || numElements != 0
value = ch.ensureIdentifier(value, reuseIdentifierExpressions, location)
}
var bindingElements []*ast.Node
var computedTempVariables []*ast.Node
for i, element := range elements {
if ast.GetRestIndicatorOfBindingOrAssignmentElement(element) == nil {
propertyName := ast.TryGetPropertyNameOfBindingOrAssignmentElement(element)
if ch.ctx.level >= flattenLevelObjectRest && element.SubtreeFacts()&(ast.SubtreeContainsRestOrSpread|ast.SubtreeContainsObjectRestOrSpread) == 0 && ast.GetTargetOfBindingOrAssignmentElement(element).SubtreeFacts()&(ast.SubtreeContainsRestOrSpread|ast.SubtreeContainsObjectRestOrSpread) == 0 && !ast.IsComputedPropertyName(propertyName) {
bindingElements = append(bindingElements, ch.Visitor().VisitNode(element))
} else {
if len(bindingElements) > 0 {
ch.ctx.emitBindingOrAssignment(ch, ch.ctx.createObjectBindingOrAssignmentPattern(ch, bindingElements), value, location, pattern)
bindingElements = nil
}
rhsValue := ch.createDestructuringPropertyAccess(value, propertyName)
if ast.IsComputedPropertyName(propertyName) {
computedTempVariables = append(computedTempVariables, rhsValue.AsElementAccessExpression().ArgumentExpression)
}
ch.flattenBindingOrAssignmentElement(element, rhsValue, element.Loc, false)
}
} else if i == numElements-1 {
if len(bindingElements) > 0 {
ch.ctx.emitBindingOrAssignment(ch, ch.ctx.createObjectBindingOrAssignmentPattern(ch, bindingElements), value, location, pattern)
bindingElements = nil
}
rhsValue := ch.Factory().NewRestHelper(value, elements, computedTempVariables, pattern.Loc)
ch.flattenBindingOrAssignmentElement(element, rhsValue, element.Loc, false)
}
}
if len(bindingElements) > 0 {
ch.ctx.emitBindingOrAssignment(ch, ch.ctx.createObjectBindingOrAssignmentPattern(ch, bindingElements), value, location, pattern)
}
}
type restIdElemPair struct {
id *ast.Node
element *ast.Node
}
func (ch *objectRestSpreadTransformer) flattenArrayBindingOrAssignmentPattern(parent *ast.Node, pattern *ast.Node, value *ast.Node, location core.TextRange) {
elements := ast.GetElementsOfBindingOrAssignmentPattern(pattern)
numElements := len(elements)
if numElements != 1 && (ch.ctx.level < flattenLevelObjectRest || numElements == 0) || core.Every(elements, ast.IsOmittedExpression) {
// For anything other than a single-element destructuring we need to generate a temporary
// to ensure value is evaluated exactly once. Additionally, if we have zero elements
// we need to emit *something* to ensure that in case a 'var' keyword was already emitted,
// so in that case, we'll intentionally create that temporary.
// Or all the elements of the binding pattern are omitted expression such as "var [,] = [1,2]",
// then we will create temporary variable.
reuseIdentifierExpressions := !ast.IsDeclarationBindingElement(parent) || numElements != 0
value = ch.ensureIdentifier(value, reuseIdentifierExpressions, location)
}
var bindingElements []*ast.Node
var restContainingElements []restIdElemPair
for i, element := range elements {
if ch.ctx.level >= flattenLevelObjectRest {
// If an array pattern contains an ObjectRest, we must cache the result so that we
// can perform the ObjectRest destructuring in a different declaration
if element.SubtreeFacts()&ast.SubtreeContainsObjectRestOrSpread != 0 || ch.ctx.hasTransformedPriorElement && !isSimpleBindingOrAssignmentElement(element) {
ch.ctx.hasTransformedPriorElement = true
temp := ch.Factory().NewTempVariable()
if ch.ctx.hoistTempVariables {
ch.EmitContext().AddVariableDeclaration(temp)
}
restContainingElements = append(restContainingElements, restIdElemPair{temp, element})
bindingElements = append(bindingElements, ch.ctx.createArrayBindingOrAssignmentElement(ch, temp))
} else {
bindingElements = append(bindingElements, element)
}
} else if ast.IsOmittedExpression(element) {
continue
} else if ast.GetRestIndicatorOfBindingOrAssignmentElement(element) == nil {
rhsValue := ch.Factory().NewElementAccessExpression(value, nil, ch.Factory().NewNumericLiteral(strconv.Itoa(i)), ast.NodeFlagsNone)
ch.flattenBindingOrAssignmentElement(element, rhsValue, element.Loc, false)
} else if i == numElements-1 {
rhsValue := ch.Factory().NewArraySliceCall(value, i)
ch.flattenBindingOrAssignmentElement(element, rhsValue, element.Loc, false)
}
}
if len(bindingElements) > 0 {
ch.ctx.emitBindingOrAssignment(ch, ch.ctx.createArrayBindingOrAssignmentPattern(ch, bindingElements), value, location, pattern)
}
if len(restContainingElements) > 0 {
for _, pair := range restContainingElements {
ch.flattenBindingOrAssignmentElement(pair.element, pair.id, pair.element.Loc, false)
}
}
}
/**
* Creates either a PropertyAccessExpression or an ElementAccessExpression for the
* right-hand side of a transformed destructuring assignment.
*
* @link https://tc39.github.io/ecma262/#sec-runtime-semantics-keyeddestructuringassignmentevaluation
*
* @param flattenContext Options used to control flattening.
* @param value The RHS value that is the source of the property.
* @param propertyName The destructuring property name.
*/
func (ch *objectRestSpreadTransformer) createDestructuringPropertyAccess(value *ast.Node, propertyName *ast.Node) *ast.Node {
if ast.IsComputedPropertyName(propertyName) {
argumentExpression := ch.ensureIdentifier(ch.Visitor().VisitNode(propertyName.AsComputedPropertyName().Expression), false, propertyName.Loc)
return ch.Factory().NewElementAccessExpression(
value,
nil,
argumentExpression,
ast.NodeFlagsNone,
)
} else if ast.IsStringOrNumericLiteralLike(propertyName) || ast.IsBigIntLiteral(propertyName) {
argumentExpression := propertyName.Clone(ch.Factory())
return ch.Factory().NewElementAccessExpression(
value,
nil,
argumentExpression,
ast.NodeFlagsNone,
)
} else {
name := ch.Factory().NewIdentifier(propertyName.AsIdentifier().Text)
return ch.Factory().NewPropertyAccessExpression(
value,
nil,
name,
ast.NodeFlagsNone,
)
}
}
func (ch *objectRestSpreadTransformer) createObjectBindingPattern(elements []*ast.Node) *ast.Node {
return ch.Factory().NewBindingPattern(ast.KindObjectBindingPattern, ch.Factory().NewNodeList(elements))
}
func (ch *objectRestSpreadTransformer) createArrayBindingPattern(elements []*ast.Node) *ast.Node {
return ch.Factory().NewBindingPattern(ast.KindArrayBindingPattern, ch.Factory().NewNodeList(elements))
}
func (ch *objectRestSpreadTransformer) createObjectAssignmentPattern(elements []*ast.Node) *ast.Node {
return ch.Factory().NewObjectLiteralExpression(ch.Factory().NewNodeList(elements), false)
}
func (ch *objectRestSpreadTransformer) createArrayAssignmentPattern(elements []*ast.Node) *ast.Node {
return ch.Factory().NewArrayLiteralExpression(ch.Factory().NewNodeList(elements), false)
}
func (ch *objectRestSpreadTransformer) createArrayAssignmentElement(expr *ast.Node) *ast.Node {
return expr
}
func (ch *objectRestSpreadTransformer) createArrayBindingElement(expr *ast.Node) *ast.Node {
return ch.Factory().NewBindingElement(nil, nil, expr, nil)
}
func (ch *objectRestSpreadTransformer) emitExpression(node *ast.Node) {
ch.ctx.currentExpressions = append(ch.ctx.currentExpressions, node)
}
func (ch *objectRestSpreadTransformer) emitAssignment(target *ast.Node, value *ast.Node, location core.TextRange, original *ast.Node) {
debug.AssertNode(target, ast.IsExpression)
expr := ch.Factory().NewAssignmentExpression(ch.Visitor().VisitNode(target), value)
expr.Loc = location
ch.EmitContext().SetOriginal(expr, original)
ch.emitExpression(expr)
}
func isBindingName(node *ast.Node) bool {
return node.Kind == ast.KindIdentifier || node.Kind == ast.KindArrayBindingPattern || node.Kind == ast.KindObjectBindingPattern
}
func (ch *objectRestSpreadTransformer) emitBinding(target *ast.Node, value *ast.Node, location core.TextRange, original *ast.Node) {
debug.AssertNode(target, isBindingName)
if len(ch.ctx.currentExpressions) > 0 {
value = ch.Factory().InlineExpressions(append(ch.ctx.currentExpressions, value))
ch.ctx.currentExpressions = nil
}
ch.ctx.currentDeclarations = append(ch.ctx.currentDeclarations, pendingDecl{
ch.ctx.currentExpressions,
target,
value,
location,
original,
})
}
func (ch *objectRestSpreadTransformer) ensureIdentifier(value *ast.Node, reuseIdentifierExpressions bool, location core.TextRange) *ast.Node {
if reuseIdentifierExpressions && ast.IsIdentifier(value) {
return value
}
temp := ch.Factory().NewTempVariable()
if ch.ctx.hoistTempVariables {
ch.EmitContext().AddVariableDeclaration(temp)
assign := ch.Factory().NewAssignmentExpression(temp, value)
assign.Loc = location
ch.emitExpression(assign)
} else {
ch.ctx.emitBindingOrAssignment(ch, temp, value, location, nil)
}
return temp
}
func (ch *objectRestSpreadTransformer) createDefaultValueCheck(value *ast.Expression, defaultValue *ast.Expression, location core.TextRange) *ast.Node {
value = ch.ensureIdentifier(value, true, location)
return ch.Factory().NewConditionalExpression(
ch.Factory().NewTypeCheck(value, "undefined"),
ch.Factory().NewToken(ast.KindQuestionToken),
defaultValue,
ch.Factory().NewToken(ast.KindColonToken),
value,
)
}
func (ch *objectRestSpreadTransformer) visitObjectLiteralExpression(node *ast.ObjectLiteralExpression) *ast.Node {
if (node.SubtreeFacts() & ast.SubtreeContainsObjectRestOrSpread) == 0 {
return ch.Visitor().VisitEachChild(node.AsNode())
}
// spread elements emit like so:
// non-spread elements are chunked together into object literals, and then all are passed to __assign:
// { a, ...o, b } => __assign(__assign({a}, o), {b});
// If the first element is a spread element, then the first argument to __assign is {}:
// { ...o, a, b, ...o2 } => __assign(__assign(__assign({}, o), {a, b}), o2)
//
// We cannot call __assign with more than two elements, since any element could cause side effects. For
// example:
// var k = { a: 1, b: 2 };
// var o = { a: 3, ...k, b: k.a++ };
// // expected: { a: 1, b: 1 }
// If we translate the above to `__assign({ a: 3 }, k, { b: k.a++ })`, the `k.a++` will evaluate before
// `k` is spread and we end up with `{ a: 2, b: 1 }`.
//
// This also occurs for spread elements, not just property assignments:
// var k = { a: 1, get b() { l = { z: 9 }; return 2; } };
// var l = { c: 3 };
// var o = { ...k, ...l };
// // expected: { a: 1, b: 2, z: 9 }
// If we translate the above to `__assign({}, k, l)`, the `l` will evaluate before `k` is spread and we
// end up with `{ a: 1, b: 2, c: 3 }`
objects := ch.chunkObjectLiteralElements(node.Properties)
if len(objects) > 0 && objects[0].Kind != ast.KindObjectLiteralExpression {
objects = append([]*ast.Node{ch.Factory().NewObjectLiteralExpression(ch.Factory().NewNodeList(nil), false)}, objects...)
}
expression := objects[0]
if len(objects) > 1 {
for i, obj := range objects {
if i == 0 {
continue
}
expression = ch.Factory().NewAssignHelper([]*ast.Node{expression, obj}, ch.compilerOptions.GetEmitScriptTarget())
}
return expression
}
return ch.Factory().NewAssignHelper(objects, ch.compilerOptions.GetEmitScriptTarget())
}
func (ch *objectRestSpreadTransformer) chunkObjectLiteralElements(list *ast.NodeList) []*ast.Node {
if list == nil || len(list.Nodes) == 0 {
return nil
}
elements := list.Nodes
var chunkObject []*ast.Node
objects := make([]*ast.Node, 0, 1)
for _, e := range elements {
if e.Kind == ast.KindSpreadAssignment {
if len(chunkObject) > 0 {
objects = append(objects, ch.Factory().NewObjectLiteralExpression(ch.Factory().NewNodeList(chunkObject), false))
chunkObject = nil
}
target := e.Expression()
objects = append(objects, ch.Visitor().VisitNode(target))
} else {
var elem *ast.Node
if e.Kind == ast.KindPropertyAssignment {
elem = ch.Factory().NewPropertyAssignment(nil, e.Name(), nil, nil, ch.Visitor().VisitNode(e.Initializer()))
} else {
elem = ch.Visitor().VisitNode(e)
}
chunkObject = append(chunkObject, elem)
}
}
if len(chunkObject) > 0 {
objects = append(objects, ch.Factory().NewObjectLiteralExpression(ch.Factory().NewNodeList(chunkObject), false))
}
return objects
}
func newObjectRestSpreadTransformer(opts *transformers.TransformOptions) *transformers.Transformer {
tx := &objectRestSpreadTransformer{compilerOptions: opts.CompilerOptions}
return tx.NewTransformer(tx.visit, opts.Context)
}
func bindingOrAssignmentElementAssignsToName(element *ast.Node, name string) bool {
target := ast.GetTargetOfBindingOrAssignmentElement(element)
if target == nil {
return false
}
if ast.IsBindingPattern(target) || ast.IsAssignmentPattern(target) {
return bindingOrAssignmentPatternAssignsToName(target, name)
} else if ast.IsIdentifier(target) {
return target.AsIdentifier().Text == name
}
return false
}
func bindingOrAssignmentPatternAssignsToName(pattern *ast.Node, name string) bool {
elements := ast.GetElementsOfBindingOrAssignmentPattern(pattern)
for _, element := range elements {
if bindingOrAssignmentElementAssignsToName(element, name) {
return true
}
}
return false
}
func bindingOrAssignmentElementContainsNonLiteralComputedName(element *ast.Node) bool {
propertyName := ast.TryGetPropertyNameOfBindingOrAssignmentElement(element)
if propertyName != nil && ast.IsComputedPropertyName(propertyName) && !ast.IsLiteralExpression(propertyName.AsComputedPropertyName().Expression) {
return true
}
target := ast.GetTargetOfBindingOrAssignmentElement(element)
return target != nil && (ast.IsBindingPattern(target) || ast.IsAssignmentPattern(target)) && bindingOrAssignmentPatternContainsNonLiteralComputedName(target)
}
func bindingOrAssignmentPatternContainsNonLiteralComputedName(pattern *ast.Node) bool {
elements := ast.GetElementsOfBindingOrAssignmentPattern(pattern)
for _, element := range elements {
if bindingOrAssignmentElementContainsNonLiteralComputedName(element) {
return true
}
}
return false
}
func getInitializerOfBindingOrAssignmentElement(bindingElement *ast.Node) *ast.Node {
if ast.IsDeclarationBindingElement(bindingElement) {
// `1` in `let { a = 1 } = ...`
// `1` in `let { a: b = 1 } = ...`
// `1` in `let { a: {b} = 1 } = ...`
// `1` in `let { a: [b] = 1 } = ...`
// `1` in `let [a = 1] = ...`
// `1` in `let [{a} = 1] = ...`
// `1` in `let [[a] = 1] = ...`
return bindingElement.Initializer()
}
if ast.IsPropertyAssignment(bindingElement) {
// `1` in `({ a: b = 1 } = ...)`
// `1` in `({ a: {b} = 1 } = ...)`
// `1` in `({ a: [b] = 1 } = ...)`
initializer := bindingElement.Initializer()
if ast.IsAssignmentExpression(initializer, true) {
return initializer.AsBinaryExpression().Right
}
return nil
}
if ast.IsShorthandPropertyAssignment(bindingElement) {
// `1` in `({ a = 1 } = ...)`
return bindingElement.AsShorthandPropertyAssignment().ObjectAssignmentInitializer
}
if ast.IsAssignmentExpression(bindingElement, true) {
// `1` in `[a = 1] = ...`
// `1` in `[{a} = 1] = ...`
// `1` in `[[a] = 1] = ...`
return bindingElement.AsBinaryExpression().Right
}
if ast.IsSpreadElement(bindingElement) {
// Recovery consistent with existing emit.
return getInitializerOfBindingOrAssignmentElement(bindingElement.Expression())
}
return nil
}
func isObjectBindingOrAssignmentPattern(node *ast.Node) bool {
return node.Kind == ast.KindObjectBindingPattern || node.Kind == ast.KindObjectLiteralExpression
}
func isArrayBindingOrAssignmentPattern(node *ast.Node) bool {
return node.Kind == ast.KindArrayBindingPattern || node.Kind == ast.KindArrayLiteralExpression
}
func isSimpleBindingOrAssignmentElement(element *ast.Node) bool {
target := ast.GetTargetOfBindingOrAssignmentElement(element)
if target == nil || ast.IsOmittedExpression(target) {
return true
}
propertyName := ast.TryGetPropertyNameOfBindingOrAssignmentElement(element)
if propertyName != nil && !ast.IsPropertyNameLiteral(propertyName) {
return false
}
initializer := getInitializerOfBindingOrAssignmentElement(element)
if initializer != nil && !transformers.IsSimpleInlineableExpression(initializer) {
return false
}
if ast.IsBindingPattern(target) || ast.IsAssignmentPattern(target) {
return core.Every(ast.GetElementsOfBindingOrAssignmentPattern(target), isSimpleBindingOrAssignmentElement)
}
return ast.IsIdentifier(target)
}