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Merged
merged 5 commits into from
Sep 10, 2025
Merged

BridgeJS: Swift -> JS Optionals support #444

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55ee129
BridgeJS: WIP: Swift Optional support Swift -> TS
krodak Sep 3, 2025
1e276d5
BridgeJS: Optional enums with associated value support
krodak Sep 4, 2025
6091dfc
BridgeJS: Support optionals in associated value enum parameters + cle…
krodak Sep 8, 2025
e41c6c4
BridgeJS: ./Utilities/bridge-js-generate.sh update
krodak Sep 10, 2025
29064b9
BridgeJS: Add missing template functions
krodak Sep 10, 2025
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12 changes: 6 additions & 6 deletions Benchmarks/Sources/Generated/BridgeJS.ExportSwift.swift
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Original file line number Diff line number Diff line change
Expand Up @@ -6,8 +6,8 @@

@_spi(BridgeJS) import JavaScriptKit

private extension APIResult {
static func bridgeJSLiftParameter(_ caseId: Int32) -> APIResult {
extension APIResult: _BridgedSwiftAssociatedValueEnum {
@_spi(BridgeJS) @_transparent public static func bridgeJSLiftParameter(_ caseId: Int32) -> APIResult {
switch caseId {
case 0:
return .success(String.bridgeJSLiftParameter(_swift_js_pop_param_int32(), _swift_js_pop_param_int32()))
Expand All @@ -26,7 +26,7 @@ private extension APIResult {
}
}

func bridgeJSLowerReturn() {
@_spi(BridgeJS) @_transparent public consuming func bridgeJSLowerReturn() {
switch self {
case .success(let param0):
_swift_js_push_tag(Int32(0))
Expand All @@ -52,8 +52,8 @@ private extension APIResult {
}
}

private extension ComplexResult {
static func bridgeJSLiftParameter(_ caseId: Int32) -> ComplexResult {
extension ComplexResult: _BridgedSwiftAssociatedValueEnum {
@_spi(BridgeJS) @_transparent public static func bridgeJSLiftParameter(_ caseId: Int32) -> ComplexResult {
switch caseId {
case 0:
return .success(String.bridgeJSLiftParameter(_swift_js_pop_param_int32(), _swift_js_pop_param_int32()))
Expand All @@ -74,7 +74,7 @@ private extension ComplexResult {
}
}

func bridgeJSLowerReturn() {
@_spi(BridgeJS) @_transparent public consuming func bridgeJSLowerReturn() {
switch self {
case .success(let param0):
_swift_js_push_tag(Int32(0))
Expand Down
153 changes: 143 additions & 10 deletions Plugins/BridgeJS/Sources/BridgeJSCore/ExportSwift.swift
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Original file line number Diff line number Diff line change
Expand Up @@ -143,6 +143,14 @@ public class ExportSwift {
)
}

private func diagnoseNestedOptional(node: some SyntaxProtocol, type: String) {
diagnose(
node: node,
message: "Nested optional types are not supported: \(type)",
hint: "Use a single optional like String? instead of String?? or Optional<Optional<T>>"
)
}

override func visit(_ node: FunctionDeclSyntax) -> SyntaxVisitorContinueKind {
switch state {
case .topLevel:
Expand Down Expand Up @@ -183,17 +191,32 @@ public class ExportSwift {

var parameters: [Parameter] = []
for param in node.signature.parameterClause.parameters {
guard let type = self.parent.lookupType(for: param.type) else {
let resolvedType = self.parent.lookupType(for: param.type)

if let type = resolvedType, case .optional(let wrappedType) = type, wrappedType.isOptional {
diagnoseNestedOptional(node: param.type, type: param.type.trimmedDescription)
continue
}

guard let type = resolvedType else {
diagnoseUnsupportedType(node: param.type, type: param.type.trimmedDescription)
continue
}

let name = param.secondName?.text ?? param.firstName.text
let label = param.firstName.text
parameters.append(Parameter(label: label, name: name, type: type))
}
let returnType: BridgeType
if let returnClause = node.signature.returnClause {
guard let type = self.parent.lookupType(for: returnClause.type) else {
let resolvedType = self.parent.lookupType(for: returnClause.type)

if let type = resolvedType, case .optional(let wrappedType) = type, wrappedType.isOptional {
diagnoseNestedOptional(node: returnClause.type, type: returnClause.type.trimmedDescription)
return nil
}

guard let type = resolvedType else {
diagnoseUnsupportedType(node: returnClause.type, type: returnClause.type.trimmedDescription)
return nil
}
Expand Down Expand Up @@ -538,12 +561,24 @@ public class ExportSwift {
switch associatedValue.type {
case .string, .int, .float, .double, .bool:
break
case .optional(let wrappedType):
switch wrappedType {
case .string, .int, .float, .double, .bool:
break
default:
diagnose(
node: node,
message: "Unsupported associated value type: \(associatedValue.type.swiftType)",
hint:
"Only primitive types and optional primitives (String?, Int?, Float?, Double?, Bool?) are supported in associated-value enums"
)
}
default:
diagnose(
node: node,
message: "Unsupported associated value type: \(associatedValue.type.swiftType)",
hint:
"Only primitive types (String, Int, Float, Double, Bool) are supported in associated-value enums"
"Only primitive types and optional primitives (String?, Int?, Float?, Double?, Bool?) are supported in associated-value enums"
)
}
}
Expand Down Expand Up @@ -712,8 +747,46 @@ public class ExportSwift {
}

func lookupType(for type: TypeSyntax) -> BridgeType? {
if let primitive = BridgeType(swiftType: type.trimmedDescription) {
return primitive
// T?
if let optionalType = type.as(OptionalTypeSyntax.self) {
let wrappedType = optionalType.wrappedType
if let baseType = lookupType(for: wrappedType) {
return .optional(baseType)
}
}
// Optional<T>
if let identifierType = type.as(IdentifierTypeSyntax.self),
identifierType.name.text == "Optional",
let genericArgs = identifierType.genericArgumentClause?.arguments,
genericArgs.count == 1,
let argType = genericArgs.first?.argument
{
if let baseType = lookupType(for: argType) {
return .optional(baseType)
}
}
// Swift.Optional<T>
if let memberType = type.as(MemberTypeSyntax.self),
let baseType = memberType.baseType.as(IdentifierTypeSyntax.self),
baseType.name.text == "Swift",
memberType.name.text == "Optional",
let genericArgs = memberType.genericArgumentClause?.arguments,
genericArgs.count == 1,
let argType = genericArgs.first?.argument
{
if let wrappedType = lookupType(for: argType) {
return .optional(wrappedType)
}
}
if let aliasDecl = typeDeclResolver.resolveTypeAlias(type) {
if let resolvedType = lookupType(for: aliasDecl.initializer.value) {
return resolvedType
}
}

let typeName = type.trimmedDescription
if let primitiveType = BridgeType(swiftType: typeName) {
return primitiveType
}

guard let typeDecl = typeDeclResolver.resolve(type) else {
Expand Down Expand Up @@ -831,9 +904,18 @@ public class ExportSwift {
} else {
argumentsToLift = liftingInfo.parameters.map { (name, _) in param.name + name.capitalizedFirstLetter }
}

let typeNameForIntrinsic: String
switch param.type {
case .optional(let wrappedType):
typeNameForIntrinsic = "Optional<\(wrappedType.swiftType)>"
default:
typeNameForIntrinsic = param.type.swiftType
}

liftedParameterExprs.append(
ExprSyntax(
"\(raw: param.type.swiftType).bridgeJSLiftParameter(\(raw: argumentsToLift.joined(separator: ", ")))"
"\(raw: typeNameForIntrinsic).bridgeJSLiftParameter(\(raw: argumentsToLift.joined(separator: ", ")))"
)
)
for (name, type) in zip(argumentsToLift, liftingInfo.parameters.map { $0.type }) {
Expand Down Expand Up @@ -1013,7 +1095,7 @@ public class ExportSwift {
let valueSwitch = (["switch self {"] + valueCases + ["}"]).joined(separator: "\n")

return """
extension \(raw: typeName) {
extension \(raw: typeName): _BridgedSwiftCaseEnum {
@_spi(BridgeJS) @_transparent public consuming func bridgeJSLowerParameter() -> Int32 {
return bridgeJSRawValue
}
Expand Down Expand Up @@ -1041,15 +1123,15 @@ public class ExportSwift {
func renderAssociatedValueEnumHelpers(_ enumDef: ExportedEnum) -> DeclSyntax {
let typeName = enumDef.swiftCallName
return """
private extension \(raw: typeName) {
static func bridgeJSLiftParameter(_ caseId: Int32) -> \(raw: typeName) {
extension \(raw: typeName): _BridgedSwiftAssociatedValueEnum {
@_spi(BridgeJS) @_transparent public static func bridgeJSLiftParameter(_ caseId: Int32) -> \(raw: typeName) {
switch caseId {
\(raw: generateStackLiftSwitchCases(enumDef: enumDef).joined(separator: "\n"))
default: fatalError("Unknown \(raw: typeName) case ID: \\(caseId)")
}
}

func bridgeJSLowerReturn() {
@_spi(BridgeJS) @_transparent public consuming func bridgeJSLowerReturn() {
switch self {
\(raw: generateReturnSwitchCases(enumDef: enumDef).joined(separator: "\n"))
}
Expand Down Expand Up @@ -1085,6 +1167,26 @@ public class ExportSwift {
return "\(paramName)Float.bridgeJSLiftParameter(_swift_js_pop_param_f32())"
case .double:
return "\(paramName)Double.bridgeJSLiftParameter(_swift_js_pop_param_f64())"
case .optional(let wrappedType):
switch wrappedType {
case .string:
return
"\(paramName)Optional<String>.bridgeJSLiftParameter(_swift_js_pop_param_int32(), _swift_js_pop_param_int32(), _swift_js_pop_param_int32())"
case .int:
return
"\(paramName)Optional<Int>.bridgeJSLiftParameter(_swift_js_pop_param_int32(), _swift_js_pop_param_int32())"
case .bool:
return
"\(paramName)Optional<Bool>.bridgeJSLiftParameter(_swift_js_pop_param_int32(), _swift_js_pop_param_int32())"
case .float:
return
"\(paramName)Optional<Float>.bridgeJSLiftParameter(_swift_js_pop_param_int32(), _swift_js_pop_param_f32())"
case .double:
return
"\(paramName)Optional<Double>.bridgeJSLiftParameter(_swift_js_pop_param_int32(), _swift_js_pop_param_f64())"
default:
return ""
}
default:
return "\(paramName)Int.bridgeJSLiftParameter(_swift_js_pop_param_int32())"
}
Expand Down Expand Up @@ -1121,6 +1223,30 @@ public class ExportSwift {
bodyLines.append("_swift_js_push_f32(\(paramName))")
case .double:
bodyLines.append("_swift_js_push_f64(\(paramName))")
case .optional(let wrappedType):
bodyLines.append("let __bjs_isSome_\(paramName) = \(paramName) != nil")
bodyLines.append("if let __bjs_unwrapped_\(paramName) = \(paramName) {")
switch wrappedType {
case .string:
bodyLines.append("var __bjs_str_\(paramName) = __bjs_unwrapped_\(paramName)")
bodyLines.append("__bjs_str_\(paramName).withUTF8 { ptr in")
bodyLines.append("_swift_js_push_string(ptr.baseAddress, Int32(ptr.count))")
bodyLines.append("}")
case .int:
bodyLines.append("_swift_js_push_int(Int32(__bjs_unwrapped_\(paramName)))")
case .bool:
bodyLines.append("_swift_js_push_int(__bjs_unwrapped_\(paramName) ? 1 : 0)")
case .float:
bodyLines.append("_swift_js_push_f32(__bjs_unwrapped_\(paramName))")
case .double:
bodyLines.append("_swift_js_push_f64(__bjs_unwrapped_\(paramName))")
default:
bodyLines.append(
"preconditionFailure(\"BridgeJS: unsupported optional wrapped type in generated code\")"
)
}
bodyLines.append("}")
bodyLines.append("_swift_js_push_int(__bjs_isSome_\(paramName) ? 1 : 0)")
default:
bodyLines.append(
"preconditionFailure(\"BridgeJS: unsupported associated value type in generated code\")"
Expand Down Expand Up @@ -1377,6 +1503,7 @@ extension BridgeType {
case .jsObject(let name?): return name
case .swiftHeapObject(let name): return name
case .void: return "Void"
case .optional(let wrappedType): return "Optional<\(wrappedType.swiftType)>"
case .caseEnum(let name): return name
case .rawValueEnum(let name, _): return name
case .associatedValueEnum(let name): return name
Expand Down Expand Up @@ -1411,6 +1538,10 @@ extension BridgeType {
case .jsObject: return .jsObject
case .swiftHeapObject: return .swiftHeapObject
case .void: return .void
case .optional(let wrappedType):
var optionalParams: [(name: String, type: WasmCoreType)] = [("isSome", .i32)]
optionalParams.append(contentsOf: try wrappedType.liftParameterInfo().parameters)
return LiftingIntrinsicInfo(parameters: optionalParams)
case .caseEnum: return .caseEnum
case .rawValueEnum(_, let rawType):
switch rawType {
Expand Down Expand Up @@ -1446,6 +1577,7 @@ extension BridgeType {
static let caseEnum = LoweringIntrinsicInfo(returnType: .i32)
static let rawValueEnum = LoweringIntrinsicInfo(returnType: .i32)
static let associatedValueEnum = LoweringIntrinsicInfo(returnType: nil)
static let optional = LoweringIntrinsicInfo(returnType: nil)
}

func loweringReturnInfo() throws -> LoweringIntrinsicInfo {
Expand All @@ -1458,6 +1590,7 @@ extension BridgeType {
case .jsObject: return .jsObject
case .swiftHeapObject: return .swiftHeapObject
case .void: return .void
case .optional: return .optional
case .caseEnum: return .caseEnum
case .rawValueEnum(_, let rawType):
switch rawType {
Expand Down
4 changes: 4 additions & 0 deletions Plugins/BridgeJS/Sources/BridgeJSCore/ImportTS.swift
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Original file line number Diff line number Diff line change
Expand Up @@ -437,6 +437,8 @@ extension BridgeType {
throw BridgeJSCoreError("swiftHeapObject is not supported in imported signatures")
case .caseEnum, .rawValueEnum, .associatedValueEnum, .namespaceEnum:
throw BridgeJSCoreError("Enum types are not yet supported in TypeScript imports")
case .optional:
throw BridgeJSCoreError("Optional types are not yet supported in TypeScript imports")
}
}

Expand Down Expand Up @@ -465,6 +467,8 @@ extension BridgeType {
throw BridgeJSCoreError("swiftHeapObject is not supported in imported signatures")
case .caseEnum, .rawValueEnum, .associatedValueEnum, .namespaceEnum:
throw BridgeJSCoreError("Enum types are not yet supported in TypeScript imports")
case .optional:
throw BridgeJSCoreError("Optional types are not yet supported in TypeScript imports")
}
}
}
Expand Down
23 changes: 23 additions & 0 deletions Plugins/BridgeJS/Sources/BridgeJSCore/TypeDeclResolver.swift
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Original file line number Diff line number Diff line change
Expand Up @@ -8,6 +8,7 @@ class TypeDeclResolver {
/// `Outer.Inner` type declaration is represented as ["Outer", "Inner"]
typealias QualifiedName = [String]
private var typeDeclByQualifiedName: [QualifiedName: TypeDecl] = [:]
private var typeAliasByQualifiedName: [QualifiedName: TypeAliasDeclSyntax] = [:]

enum Error: Swift.Error {
case typeNotFound(QualifiedName)
Expand Down Expand Up @@ -62,6 +63,13 @@ class TypeDeclResolver {
override func visitPost(_ node: EnumDeclSyntax) {
visitPostNominalDecl()
}

override func visit(_ node: TypeAliasDeclSyntax) -> SyntaxVisitorContinueKind {
let name = node.name.text
let qualifiedName = scope.map(\.name.text) + [name]
resolver.typeAliasByQualifiedName[qualifiedName] = node
return .skipChildren
}
}

/// Collects type declarations from a parsed Swift source file
Expand Down Expand Up @@ -132,6 +140,21 @@ class TypeDeclResolver {
return nil
}

/// Resolves a type usage node to a type alias declaration
///
/// - Parameter type: The SwiftSyntax node representing a type appearance in source code.
/// - Returns: The type alias declaration if found, otherwise nil.
func resolveTypeAlias(_ type: TypeSyntax) -> TypeAliasDeclSyntax? {
if let id = type.as(IdentifierTypeSyntax.self) {
let qualifiedName = tryQualify(type: id)
return typeAliasByQualifiedName[qualifiedName]
}
if let components = qualifiedComponents(from: type) {
return typeAliasByQualifiedName[components]
}
return nil
}

private func qualifiedComponents(from type: TypeSyntax) -> QualifiedName? {
if let m = type.as(MemberTypeSyntax.self) {
guard let base = qualifiedComponents(from: TypeSyntax(m.baseType)) else { return nil }
Expand Down
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