Port inlay hints

internal/ast/ast.go

@@ -412,6 +412,18 @@ func (n *Node) Expression() *Node {
 	panic("Unhandled case in Node.Expression: " + n.Kind.String())
 }
 
+func (n *Node) RawText() string {
+	switch n.Kind {
+	case KindTemplateHead:
+		return n.AsTemplateHead().RawText
+	case KindTemplateMiddle:
+		return n.AsTemplateMiddle().RawText
+	case KindTemplateTail:
+		return n.AsTemplateTail().RawText
+	}
+	panic("Unhandled case in Node.RawText: " + n.Kind.String())
+}
+
 func (m *mutableNode) SetExpression(expr *Node) {
 	n := (*Node)(m)
 	switch n.Kind {
@@ -2057,59 +2069,63 @@ type NodeBase struct {
 // Aliases for Node unions
 
 type (
-	Statement                   = Node // Node with StatementBase
-	Declaration                 = Node // Node with DeclarationBase
-	Expression                  = Node // Node with ExpressionBase
-	TypeNode                    = Node // Node with TypeNodeBase
-	TypeElement                 = Node // Node with TypeElementBase
-	ClassElement                = Node // Node with ClassElementBase
-	NamedMember                 = Node // Node with NamedMemberBase
-	ObjectLiteralElement        = Node // Node with ObjectLiteralElementBase
-	BlockOrExpression           = Node // Block | Expression
-	AccessExpression            = Node // PropertyAccessExpression | ElementAccessExpression
-	DeclarationName             = Node // Identifier | PrivateIdentifier | StringLiteral | NumericLiteral | BigIntLiteral | NoSubstitutionTemplateLiteral | ComputedPropertyName | BindingPattern | ElementAccessExpression
-	ModuleName                  = Node // Identifier | StringLiteral
-	ModuleExportName            = Node // Identifier | StringLiteral
-	PropertyName                = Node // Identifier | StringLiteral | NoSubstitutionTemplateLiteral | NumericLiteral | ComputedPropertyName | PrivateIdentifier | BigIntLiteral
-	ModuleBody                  = Node // ModuleBlock | ModuleDeclaration
-	ForInitializer              = Node // Expression | MissingDeclaration | VariableDeclarationList
-	ModuleReference             = Node // Identifier | QualifiedName | ExternalModuleReference
-	NamedImportBindings         = Node // NamespaceImport | NamedImports
-	NamedExportBindings         = Node // NamespaceExport | NamedExports
-	MemberName                  = Node // Identifier | PrivateIdentifier
-	EntityName                  = Node // Identifier | QualifiedName
-	BindingName                 = Node // Identifier | BindingPattern
-	ModifierLike                = Node // Modifier | Decorator
-	JsxChild                    = Node // JsxText | JsxExpression | JsxElement | JsxSelfClosingElement | JsxFragment
-	JsxAttributeLike            = Node // JsxAttribute | JsxSpreadAttribute
-	JsxAttributeName            = Node // Identifier | JsxNamespacedName
-	JsxAttributeValue           = Node // StringLiteral | JsxExpression | JsxElement | JsxSelfClosingElement | JsxFragment
-	JsxTagNameExpression        = Node // IdentifierReference | KeywordExpression | JsxTagNamePropertyAccess | JsxNamespacedName
-	ClassLikeDeclaration        = Node // ClassDeclaration | ClassExpression
-	AccessorDeclaration         = Node // GetAccessorDeclaration | SetAccessorDeclaration
-	LiteralLikeNode             = Node // StringLiteral | NumericLiteral | BigIntLiteral | RegularExpressionLiteral | TemplateLiteralLikeNode | JsxText
-	LiteralExpression           = Node // StringLiteral | NumericLiteral | BigIntLiteral | RegularExpressionLiteral | NoSubstitutionTemplateLiteral
-	UnionOrIntersectionTypeNode = Node // UnionTypeNode | IntersectionTypeNode
-	TemplateLiteralLikeNode     = Node // TemplateHead | TemplateMiddle | TemplateTail
-	TemplateMiddleOrTail        = Node // TemplateMiddle | TemplateTail
-	TemplateLiteral             = Node // TemplateExpression | NoSubstitutionTemplateLiteral
-	TypePredicateParameterName  = Node // Identifier | ThisTypeNode
-	ImportAttributeName         = Node // Identifier | StringLiteral
-	LeftHandSideExpression      = Node // subset of Expression
-	JSDocComment                = Node // JSDocText | JSDocLink | JSDocLinkCode | JSDocLinkPlain;
-	JSDocTag                    = Node // Node with JSDocTagBase
-	SignatureDeclaration        = Node // CallSignatureDeclaration | ConstructSignatureDeclaration | MethodSignature | IndexSignatureDeclaration | FunctionTypeNode | ConstructorTypeNode | FunctionDeclaration | MethodDeclaration | ConstructorDeclaration | AccessorDeclaration | FunctionExpression | ArrowFunction;
-	StringLiteralLike           = Node // StringLiteral | NoSubstitutionTemplateLiteral
-	AnyValidImportOrReExport    = Node // (ImportDeclaration | ExportDeclaration | JSDocImportTag) & { moduleSpecifier: StringLiteral } | ImportEqualsDeclaration & { moduleReference: ExternalModuleReference & { expression: StringLiteral }} | RequireOrImportCall | ValidImportTypeNode
-	ValidImportTypeNode         = Node // ImportTypeNode & { argument: LiteralTypeNode & { literal: StringLiteral } }
-	NumericOrStringLikeLiteral  = Node // StringLiteralLike | NumericLiteral
-	TypeOnlyImportDeclaration   = Node // ImportClause | ImportEqualsDeclaration | ImportSpecifier | NamespaceImport with isTypeOnly: true
-	ObjectLiteralLike           = Node // ObjectLiteralExpression | ObjectBindingPattern
-	ObjectTypeDeclaration       = Node // ClassLikeDeclaration | InterfaceDeclaration | TypeLiteralNode
-	JsxOpeningLikeElement       = Node // JsxOpeningElement | JsxSelfClosingElement
-	NamedImportsOrExports       = Node // NamedImports | NamedExports
-	BreakOrContinueStatement    = Node // BreakStatement | ContinueStatement
-	CallLikeExpression          = Node // CallExpression | NewExpression | TaggedTemplateExpression | Decorator | JsxCallLike | InstanceofExpression
+	Statement                      = Node // Node with StatementBase
+	Declaration                    = Node // Node with DeclarationBase
+	Expression                     = Node // Node with ExpressionBase
+	TypeNode                       = Node // Node with TypeNodeBase
+	TypeElement                    = Node // Node with TypeElementBase
+	ClassElement                   = Node // Node with ClassElementBase
+	NamedMember                    = Node // Node with NamedMemberBase
+	ObjectLiteralElement           = Node // Node with ObjectLiteralElementBase
+	BlockOrExpression              = Node // Block | Expression
+	AccessExpression               = Node // PropertyAccessExpression | ElementAccessExpression
+	DeclarationName                = Node // Identifier | PrivateIdentifier | StringLiteral | NumericLiteral | BigIntLiteral | NoSubstitutionTemplateLiteral | ComputedPropertyName | BindingPattern | ElementAccessExpression
+	ModuleName                     = Node // Identifier | StringLiteral
+	ModuleExportName               = Node // Identifier | StringLiteral
+	PropertyName                   = Node // Identifier | StringLiteral | NoSubstitutionTemplateLiteral | NumericLiteral | ComputedPropertyName | PrivateIdentifier | BigIntLiteral
+	ModuleBody                     = Node // ModuleBlock | ModuleDeclaration
+	ForInitializer                 = Node // Expression | MissingDeclaration | VariableDeclarationList
+	ModuleReference                = Node // Identifier | QualifiedName | ExternalModuleReference
+	NamedImportBindings            = Node // NamespaceImport | NamedImports
+	NamedExportBindings            = Node // NamespaceExport | NamedExports
+	MemberName                     = Node // Identifier | PrivateIdentifier
+	EntityName                     = Node // Identifier | QualifiedName
+	BindingName                    = Node // Identifier | BindingPattern
+	ModifierLike                   = Node // Modifier | Decorator
+	JsxChild                       = Node // JsxText | JsxExpression | JsxElement | JsxSelfClosingElement | JsxFragment
+	JsxAttributeLike               = Node // JsxAttribute | JsxSpreadAttribute
+	JsxAttributeName               = Node // Identifier | JsxNamespacedName
+	JsxAttributeValue              = Node // StringLiteral | JsxExpression | JsxElement | JsxSelfClosingElement | JsxFragment
+	JsxTagNameExpression           = Node // IdentifierReference | KeywordExpression | JsxTagNamePropertyAccess | JsxNamespacedName
+	ClassLikeDeclaration           = Node // ClassDeclaration | ClassExpression
+	AccessorDeclaration            = Node // GetAccessorDeclaration | SetAccessorDeclaration
+	LiteralLikeNode                = Node // StringLiteral | NumericLiteral | BigIntLiteral | RegularExpressionLiteral | TemplateLiteralLikeNode | JsxText
+	LiteralExpression              = Node // StringLiteral | NumericLiteral | BigIntLiteral | RegularExpressionLiteral | NoSubstitutionTemplateLiteral
+	UnionOrIntersectionTypeNode    = Node // UnionTypeNode | IntersectionTypeNode
+	TemplateLiteralLikeNode        = Node // TemplateHead | TemplateMiddle | TemplateTail
+	TemplateMiddleOrTail           = Node // TemplateMiddle | TemplateTail
+	TemplateLiteral                = Node // TemplateExpression | NoSubstitutionTemplateLiteral
+	TypePredicateParameterName     = Node // Identifier | ThisTypeNode
+	ImportAttributeName            = Node // Identifier | StringLiteral
+	LeftHandSideExpression         = Node // subset of Expression
+	JSDocComment                   = Node // JSDocText | JSDocLink | JSDocLinkCode | JSDocLinkPlain;
+	JSDocTag                       = Node // Node with JSDocTagBase
+	SignatureDeclaration           = Node // CallSignatureDeclaration | ConstructSignatureDeclaration | MethodSignature | IndexSignatureDeclaration | FunctionTypeNode | ConstructorTypeNode | FunctionDeclaration | MethodDeclaration | ConstructorDeclaration | AccessorDeclaration | FunctionExpression | ArrowFunction;
+	StringLiteralLike              = Node // StringLiteral | NoSubstitutionTemplateLiteral
+	AnyValidImportOrReExport       = Node // (ImportDeclaration | ExportDeclaration | JSDocImportTag) & { moduleSpecifier: StringLiteral } | ImportEqualsDeclaration & { moduleReference: ExternalModuleReference & { expression: StringLiteral }} | RequireOrImportCall | ValidImportTypeNode
+	ValidImportTypeNode            = Node // ImportTypeNode & { argument: LiteralTypeNode & { literal: StringLiteral } }
+	NumericOrStringLikeLiteral     = Node // StringLiteralLike | NumericLiteral
+	TypeOnlyImportDeclaration      = Node // ImportClause | ImportEqualsDeclaration | ImportSpecifier | NamespaceImport with isTypeOnly: true
+	ObjectLiteralLike              = Node // ObjectLiteralExpression | ObjectBindingPattern
+	ObjectTypeDeclaration          = Node // ClassLikeDeclaration | InterfaceDeclaration | TypeLiteralNode
+	JsxOpeningLikeElement          = Node // JsxOpeningElement | JsxSelfClosingElement
+	NamedImportsOrExports          = Node // NamedImports | NamedExports
+	BreakOrContinueStatement       = Node // BreakStatement | ContinueStatement
+	CallLikeExpression             = Node // CallExpression | NewExpression | TaggedTemplateExpression | Decorator | JsxCallLike | InstanceofExpression
+	FunctionLikeDeclaration        = Node // FunctionDeclaration | MethodDeclaration | GetAccessorDeclaration | SetAccessorDeclaration | ConstructorDeclaration | FunctionExpression | ArrowFunction
+	VariableOrParameterDeclaration = Node // VariableDeclaration | ParameterDeclaration
+	VariableOrPropertyDeclaration  = Node // VariableDeclaration | PropertyDeclaration
+	CallOrNewExpression            = Node // CallExpression | NewExpression
 )
 
 // Aliases for node singletons
@@ -2160,6 +2176,7 @@ type (
 	LiteralType                     = Node
 	JSDocNode                       = Node
 	BindingPatternNode              = Node
+	TypePredicateNodeNode           = Node
 )
 
 type (

internal/ast/utilities.go

@@ -3860,3 +3860,26 @@ func IsJSDocNameReferenceContext(node *Node) bool {
 func IsImportOrImportEqualsDeclaration(node *Node) bool {
 	return IsImportDeclaration(node) || IsImportEqualsDeclaration(node)
 }
+
+func HasContextSensitiveParameters(node *Node) bool {
+	// Functions with type parameters are not context sensitive.
+	if node.TypeParameters() == nil {
+		// Functions with any parameters that lack type annotations are context sensitive.
+		if core.Some(node.Parameters(), func(p *Node) bool { return p.Type() == nil }) {
+			return true
+		}
+		if !IsArrowFunction(node) {
+			// If the first parameter is not an explicit 'this' parameter, then the function has
+			// an implicit 'this' parameter which is subject to contextual typing.
+			parameter := core.FirstOrNil(node.Parameters())
+			if parameter == nil || !IsThisParameter(parameter) {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+func IsInfinityOrNaNString(name string) bool {
+	return name == "Infinity" || name == "-Infinity" || name == "NaN"
+}

internal/checker/checker.go

@@ -9763,7 +9763,7 @@ func (c *Checker) checkFunctionExpressionOrObjectLiteralMethod(node *ast.Node, c
 	}
 	if checkMode&CheckModeSkipContextSensitive != 0 && c.isContextSensitive(node) {
 		// Skip parameters, return signature with return type that retains noncontextual parts so inferences can still be drawn in an early stage
-		if node.Type() == nil && !hasContextSensitiveParameters(node) {
+		if node.Type() == nil && !ast.HasContextSensitiveParameters(node) {
 			// Return plain anyFunctionType if there is no possibility we'll make inferences from the return type
 			contextualSignature := c.getContextualSignature(node)
 			if contextualSignature != nil && c.couldContainTypeVariables(c.getReturnTypeOfSignature(contextualSignature)) {
@@ -23053,7 +23053,7 @@ func (c *Checker) computeEnumMemberValue(member *ast.Node, autoValue jsnum.Numbe
 		c.error(member.Name(), diagnostics.Computed_property_names_are_not_allowed_in_enums)
 	} else {
 		text := ast.GetTextOfPropertyName(member.Name())
-		if isNumericLiteralName(text) && !isInfinityOrNaNString(text) {
+		if isNumericLiteralName(text) && !ast.IsInfinityOrNaNString(text) {
 			c.error(member.Name(), diagnostics.An_enum_member_cannot_have_a_numeric_name)
 		}
 	}
@@ -23120,7 +23120,7 @@ func (c *Checker) evaluateEntity(expr *ast.Node, location *ast.Node) evaluator.R
 			return evaluator.NewResult(nil, false, false, false)
 		}
 		if expr.Kind == ast.KindIdentifier {
-			if isInfinityOrNaNString(expr.Text()) && (symbol == c.getGlobalSymbol(expr.Text(), ast.SymbolFlagsValue, nil /*diagnostic*/)) {
+			if ast.IsInfinityOrNaNString(expr.Text()) && (symbol == c.getGlobalSymbol(expr.Text(), ast.SymbolFlagsValue, nil /*diagnostic*/)) {
 				// Technically we resolved a global lib file here, but the decision to treat this as numeric
 				// is more predicated on the fact that the single-file resolution *didn't* resolve to a
 				// different meaning of `Infinity` or `NaN`. Transpilers handle this no problem.
@@ -29554,7 +29554,7 @@ func (c *Checker) isContextSensitive(node *ast.Node) bool {
 }
 
 func (c *Checker) isContextSensitiveFunctionLikeDeclaration(node *ast.Node) bool {
-	return hasContextSensitiveParameters(node) || c.hasContextSensitiveReturnExpression(node)
+	return ast.HasContextSensitiveParameters(node) || c.hasContextSensitiveReturnExpression(node)
 }
 
 func (c *Checker) hasContextSensitiveReturnExpression(node *ast.Node) bool {

internal/checker/grammarchecks.go

@@ -214,7 +214,7 @@ func (c *Checker) checkGrammarModifiers(node *ast.Node /*Union[HasModifiers, Has
 	if c.reportObviousDecoratorErrors(node) || c.reportObviousModifierErrors(node) {
 		return true
 	}
-	if ast.IsParameter(node) && ast.IsThisParameter(node) {
+	if ast.IsThisParameter(node) {
 		return c.grammarErrorOnFirstToken(node, diagnostics.Neither_decorators_nor_modifiers_may_be_applied_to_this_parameters)
 	}
 	blockScopeKind := ast.NodeFlagsNone

internal/checker/printer.go

@@ -12,7 +12,7 @@ func createPrinterWithDefaults(emitContext *printer.EmitContext) *printer.Printe
 	return printer.NewPrinter(printer.PrinterOptions{}, printer.PrintHandlers{}, emitContext)
 }
 
-func createPrinterWithRemoveComments(emitContext *printer.EmitContext) *printer.Printer {
+func CreatePrinterWithRemoveComments(emitContext *printer.EmitContext) *printer.Printer {
 	return printer.NewPrinter(printer.PrinterOptions{RemoveComments: true}, printer.PrintHandlers{}, emitContext)
 }
 
@@ -199,7 +199,7 @@ func (c *Checker) typeToStringEx(t *Type, enclosingDeclaration *ast.Node, flags
 	if t == c.unresolvedType {
 		printer = createPrinterWithDefaults(nodeBuilder.EmitContext())
 	} else {
-		printer = createPrinterWithRemoveComments(nodeBuilder.EmitContext())
+		printer = CreatePrinterWithRemoveComments(nodeBuilder.EmitContext())
 	}
 	var sourceFile *ast.SourceFile
 	if enclosingDeclaration != nil {
@@ -262,7 +262,7 @@ func (c *Checker) symbolToStringEx(symbol *ast.Symbol, enclosingDeclaration *ast
 	if enclosingDeclaration != nil && enclosingDeclaration.Kind == ast.KindSourceFile {
 		printer_ = createPrinterWithRemoveCommentsNeverAsciiEscape(nodeBuilder.EmitContext())
 	} else {
-		printer_ = createPrinterWithRemoveComments(nodeBuilder.EmitContext())
+		printer_ = CreatePrinterWithRemoveComments(nodeBuilder.EmitContext())
 	}
 
 	var builder func(symbol *ast.Symbol, meaning ast.SymbolFlags, enclosingDeclaration *ast.Node, flags nodebuilder.Flags, internalFlags nodebuilder.InternalFlags, tracker nodebuilder.SymbolTracker) *ast.Node
@@ -325,7 +325,7 @@ func (c *Checker) typePredicateToStringEx(typePredicate *TypePredicate, enclosin
 	nodeBuilder := c.getNodeBuilder()
 	combinedFlags := toNodeBuilderFlags(flags) | nodebuilder.FlagsIgnoreErrors | nodebuilder.FlagsWriteTypeParametersInQualifiedName
 	predicate := nodeBuilder.TypePredicateToTypePredicateNode(typePredicate, enclosingDeclaration, combinedFlags, nodebuilder.InternalFlagsNone, nil) // TODO: GH#18217
-	printer_ := createPrinterWithRemoveComments(nodeBuilder.EmitContext())
+	printer_ := CreatePrinterWithRemoveComments(nodeBuilder.EmitContext())
 	var sourceFile *ast.SourceFile
 	if enclosingDeclaration != nil {
 		sourceFile = ast.GetSourceFileOfNode(enclosingDeclaration)
@@ -377,3 +377,8 @@ func (c *Checker) TypeToTypeNode(t *Type, enclosingDeclaration *ast.Node, flags
 	nodeBuilder := c.getNodeBuilder()
 	return nodeBuilder.TypeToTypeNode(t, enclosingDeclaration, flags, nodebuilder.InternalFlagsNone, nil)
 }
+
+func (c *Checker) TypePredicateToTypePredicateNode(t *TypePredicate, enclosingDeclaration *ast.Node, flags nodebuilder.Flags) *ast.TypePredicateNodeNode {
+	nodeBuilder := c.getNodeBuilder()
+	return nodeBuilder.TypePredicateToTypePredicateNode(t, enclosingDeclaration, flags, nodebuilder.InternalFlagsNone, nil)
+}

internal/checker/services.go

@@ -833,3 +833,7 @@ func isArrayLiteralOrObjectLiteralDestructuringPattern(node *ast.Node) bool {
 	// [x, [a, b, c] ] = someExpression
 	return isArrayLiteralOrObjectLiteralDestructuringPattern(parent)
 }
+
+func (c *Checker) GetSignatureFromDeclaration(node *ast.Node) *Signature {
+	return c.getSignatureFromDeclaration(node)
+}

internal/checker/types.go

@@ -716,6 +716,10 @@ func (t *Type) IsIndex() bool {
 	return t.flags&TypeFlagsIndex != 0
 }
 
+func (t *Type) IsTupleType() bool {
+	return isTupleType(t)
+}
+
 // TypeData
 
 type TypeData interface {
@@ -929,6 +933,7 @@ type TupleElementInfo struct {
 }
 
 func (t *TupleElementInfo) TupleElementFlags() ElementFlags { return t.flags }
+func (t *TupleElementInfo) LabeledDeclaration() *ast.Node   { return t.labeledDeclaration }
 
 type TupleType struct {
 	InterfaceType
@@ -947,6 +952,7 @@ func (t *TupleType) ElementFlags() []ElementFlags {
 	}
 	return elementFlags
 }
+func (t *TupleType) ElementInfos() []TupleElementInfo { return t.elementInfos }
 
 // SingleSignatureType
 
@@ -1192,6 +1198,10 @@ type TypePredicate struct {
 	t              *Type
 }
 
+func (typePredicate *TypePredicate) Type() *Type {
+	return typePredicate.t
+}
+
 // IndexInfo
 
 type IndexInfo struct {