BridgeJS: Initial protocol support

[fe09c4b1] Simplify export swift
[b42bb7c1] WIP: Simplify protocol method generation
[75e1ed37] BridgeJSLink simplification
[b1fcc4d0] Cleanup
[70aa0332] WIP: Final wrap
[2f648eaf] WIP: Protocols simplification
[f2f89b33] WIP: Fix for parameters in methods
[6026fc1d] WIP: Test protocol methods with parameters

Author: krodak

Benchmarks/Sources/Generated/JavaScript/BridgeJS.ExportSwift.json

@@ -720,5 +720,8 @@
       }
     }
   ],
-  "moduleName" : "Benchmarks"
+  "moduleName" : "Benchmarks",
+  "protocols" : [
+
+  ]
 }

Examples/PlayBridgeJS/Sources/PlayBridgeJS/Generated/JavaScript/BridgeJS.ExportSwift.json

@@ -138,5 +138,8 @@
   "functions" : [
 
   ],
-  "moduleName" : "PlayBridgeJS"
+  "moduleName" : "PlayBridgeJS",
+  "protocols" : [
+
+  ]
 }

Plugins/BridgeJS/Sources/BridgeJSCore/ExportSwift.swift

@@ -435,6 +435,8 @@ extension BridgeType {
         case .void: return .void
         case .swiftHeapObject:
             throw BridgeJSCoreError("swiftHeapObject is not supported in imported signatures")
+        case .swiftProtocol:
+            throw BridgeJSCoreError("swiftProtocol is not supported in imported signatures")
         case .caseEnum, .rawValueEnum, .associatedValueEnum, .namespaceEnum:
             throw BridgeJSCoreError("Enum types are not yet supported in TypeScript imports")
         case .optional:
@@ -465,6 +467,8 @@ extension BridgeType {
         case .void: return .void
         case .swiftHeapObject:
             throw BridgeJSCoreError("swiftHeapObject is not supported in imported signatures")
+        case .swiftProtocol:
+            throw BridgeJSCoreError("swiftProtocol is not supported in imported signatures")
         case .caseEnum, .rawValueEnum, .associatedValueEnum, .namespaceEnum:
             throw BridgeJSCoreError("Enum types are not yet supported in TypeScript imports")
         case .optional:

Plugins/BridgeJS/Sources/BridgeJSCore/ImportTS.swift

@@ -240,7 +240,9 @@ struct BridgeJSLink {
                     enumPropertyPrinter.write("},")
 
                     if !property.isReadonly {
-                        let setterThunkBuilder = ExportedThunkBuilder(effects: Effects(isAsync: false, isThrows: false))
+                        let setterThunkBuilder = ExportedThunkBuilder(
+                            effects: Effects(isAsync: false, isThrows: false)
+                        )
                         try setterThunkBuilder.lowerParameter(
                             param: Parameter(label: "value", name: "value", type: property.type)
                         )
@@ -300,6 +302,29 @@ struct BridgeJSLink {
             data.importObjectBuilders.append(importObjectBuilder)
         }
 
+        for skeleton in exportedSkeletons {
+            if !skeleton.protocols.isEmpty {
+                let importObjectBuilder: ImportObjectBuilder
+                if let existingBuilder = data.importObjectBuilders.first(where: { $0.moduleName == skeleton.moduleName }
+                ) {
+                    importObjectBuilder = existingBuilder
+                } else {
+                    importObjectBuilder = ImportObjectBuilder(moduleName: skeleton.moduleName)
+                    data.importObjectBuilders.append(importObjectBuilder)
+                }
+
+                for proto in skeleton.protocols {
+                    for method in proto.methods {
+                        try renderProtocolMethod(
+                            importObjectBuilder: importObjectBuilder,
+                            protocol: proto,
+                            method: method
+                        )
+                    }
+                }
+            }
+        }
+
         return data
     }
 
@@ -572,6 +597,22 @@ struct BridgeJSLink {
             """
         let printer = CodeFragmentPrinter(header: header)
         printer.nextLine()
+
+        for skeleton in exportedSkeletons {
+            for proto in skeleton.protocols {
+                printer.write("export interface \(proto.name) {")
+                printer.indent {
+                    for method in proto.methods {
+                        printer.write(
+                            "\(method.name)\(renderTSSignature(parameters: method.parameters, returnType: method.returnType, effects: method.effects));"
+                        )
+                    }
+                }
+                printer.write("}")
+                printer.nextLine()
+            }
+        }
+
         printer.write(lines: data.topLevelDtsEnumLines)
 
         // Generate Object types for const-style enums
@@ -1468,7 +1509,9 @@ extension BridgeJSLink {
 
         if !property.isReadonly {
             // Generate setter
-            let setterThunkBuilder = ExportedThunkBuilder(effects: Effects(isAsync: false, isThrows: false))
+            let setterThunkBuilder = ExportedThunkBuilder(
+                effects: Effects(isAsync: false, isThrows: false)
+            )
             try setterThunkBuilder.lowerParameter(
                 param: Parameter(label: "value", name: "value", type: property.type)
             )
@@ -1539,7 +1582,9 @@ extension BridgeJSLink {
 
         if !property.isReadonly {
             // Generate setter
-            let setterThunkBuilder = ExportedThunkBuilder(effects: Effects(isAsync: false, isThrows: false))
+            let setterThunkBuilder = ExportedThunkBuilder(
+                effects: Effects(isAsync: false, isThrows: false)
+            )
             try setterThunkBuilder.lowerParameter(
                 param: Parameter(label: "value", name: "value", type: property.type)
             )
@@ -1704,7 +1749,9 @@ extension BridgeJSLink {
 
                 // Generate static property setter if not readonly
                 if !property.isReadonly {
-                    let setterThunkBuilder = ExportedThunkBuilder(effects: Effects(isAsync: false, isThrows: false))
+                    let setterThunkBuilder = ExportedThunkBuilder(
+                        effects: Effects(isAsync: false, isThrows: false)
+                    )
                     try setterThunkBuilder.lowerParameter(
                         param: Parameter(label: "value", name: "value", type: property.type)
                     )
@@ -1752,7 +1799,9 @@ extension BridgeJSLink {
 
                 // Generate instance property setter if not readonly
                 if !property.isReadonly {
-                    let setterThunkBuilder = ExportedThunkBuilder(effects: Effects(isAsync: false, isThrows: false))
+                    let setterThunkBuilder = ExportedThunkBuilder(
+                        effects: Effects(isAsync: false, isThrows: false)
+                    )
                     setterThunkBuilder.lowerSelf()
                     try setterThunkBuilder.lowerParameter(
                         param: Parameter(label: "value", name: "value", type: property.type)
@@ -2367,6 +2416,25 @@ extension BridgeJSLink {
         )
         return (funcLines, [])
     }
+
+    func renderProtocolMethod(
+        importObjectBuilder: ImportObjectBuilder,
+        protocol: ExportedProtocol,
+        method: ExportedFunction
+    ) throws {
+        let thunkBuilder = ImportedThunkBuilder()
+        thunkBuilder.liftSelf()
+        for param in method.parameters {
+            try thunkBuilder.liftParameter(param: param)
+        }
+        let returnExpr = try thunkBuilder.callMethod(name: method.name, returnType: method.returnType)
+        let funcLines = thunkBuilder.renderFunction(
+            name: method.abiName,
+            returnExpr: returnExpr,
+            returnType: method.returnType
+        )
+        importObjectBuilder.assignToImportObject(name: method.abiName, function: funcLines)
+    }
 }
 
 struct BridgeJSLinkError: Error {
@@ -2402,6 +2470,8 @@ extension BridgeType {
             return "\(name)Tag"
         case .namespaceEnum(let name):
             return name
+        case .swiftProtocol(let name):
+            return name
         }
     }
 }

Plugins/BridgeJS/Sources/BridgeJSLink/BridgeJSLink.swift

@@ -297,6 +297,25 @@ struct IntrinsicJSFragment: Sendable {
                     switch wrappedType {
                     case .swiftHeapObject:
                         return ["+\(isSomeVar)", "\(isSomeVar) ? \(value).pointer : 0"]
+                    case .swiftProtocol:
+                        return [
+                            "+\(isSomeVar)",
+                            "\(isSomeVar) ? \(JSGlueVariableScope.reservedSwift).memory.retain(\(value)) : 0",
+                        ]
+                    case .jsObject:
+                        let idVar = scope.variable("id")
+                        printer.write("let \(idVar);")
+                        printer.write("if (\(isSomeVar)) {")
+                        printer.indent {
+                            printer.write("\(idVar) = \(JSGlueVariableScope.reservedSwift).memory.retain(\(value));")
+                        }
+                        printer.write("}")
+                        cleanupCode.write("if (\(idVar) !== undefined) {")
+                        cleanupCode.indent {
+                            cleanupCode.write("\(JSGlueVariableScope.reservedSwift).memory.release(\(idVar));")
+                        }
+                        cleanupCode.write("}")
+                        return ["+\(isSomeVar)", "\(isSomeVar) ? \(idVar) : 0"]
                     default:
                         return ["+\(isSomeVar)", "\(isSomeVar) ? \(value) : 0"]
                     }
@@ -326,6 +345,9 @@ struct IntrinsicJSFragment: Sendable {
                 case .string:
                     printer.write("const \(resultVar) = \(JSGlueVariableScope.reservedStorageToReturnString);")
                     printer.write("\(JSGlueVariableScope.reservedStorageToReturnString) = undefined;")
+                case .jsObject, .swiftProtocol:
+                    printer.write("const \(resultVar) = \(JSGlueVariableScope.reservedStorageToReturnString);")
+                    printer.write("\(JSGlueVariableScope.reservedStorageToReturnString) = undefined;")
                 case .swiftHeapObject(let className):
                     let pointerVar = scope.variable("pointer")
                     printer.write(
@@ -397,6 +419,7 @@ struct IntrinsicJSFragment: Sendable {
         case .jsObject: return .jsObjectLowerParameter
         case .swiftHeapObject:
             return .swiftHeapObjectLowerParameter
+        case .swiftProtocol: return .jsObjectLowerParameter
         case .void: return .void
         case .optional(let wrappedType):
             return try .optionalLowerParameter(wrappedType: wrappedType)
@@ -422,6 +445,7 @@ struct IntrinsicJSFragment: Sendable {
         case .string: return .stringLiftReturn
         case .jsObject: return .jsObjectLiftReturn
         case .swiftHeapObject(let name): return .swiftHeapObjectLiftReturn(name)
+        case .swiftProtocol: return .jsObjectLiftReturn
         case .void: return .void
         case .optional(let wrappedType): return .optionalLiftReturn(wrappedType: wrappedType)
         case .caseEnum: return .identity
@@ -455,6 +479,7 @@ struct IntrinsicJSFragment: Sendable {
                 message:
                     "Swift heap objects are not supported to be passed as parameters to imported JS functions: \(name)"
             )
+        case .swiftProtocol: return .jsObjectLiftParameter
         case .void:
             throw BridgeJSLinkError(
                 message: "Void can't appear in parameters of imported JS functions"
@@ -494,6 +519,7 @@ struct IntrinsicJSFragment: Sendable {
             throw BridgeJSLinkError(
                 message: "Swift heap objects are not supported to be returned from imported JS functions"
             )
+        case .swiftProtocol: return .jsObjectLowerReturn
         case .void: return .void
         case .optional(let wrappedType):
             throw BridgeJSLinkError(

Plugins/BridgeJS/Sources/BridgeJSLink/JSGlueGen.swift

@@ -74,6 +74,7 @@ public enum BridgeType: Codable, Equatable, Sendable {
     case rawValueEnum(String, SwiftEnumRawType)
     case associatedValueEnum(String)
     case namespaceEnum(String)
+    case swiftProtocol(String)
 }
 
 public enum WasmCoreType: String, Codable, Sendable {
@@ -269,6 +270,18 @@ public enum EnumType: String, Codable, Sendable {
 
 // MARK: - Exported Skeleton
 
+public struct ExportedProtocol: Codable, Equatable {
+    public let name: String
+    public let methods: [ExportedFunction]
+    public let namespace: [String]?
+
+    public init(name: String, methods: [ExportedFunction], namespace: [String]? = nil) {
+        self.name = name
+        self.methods = methods
+        self.namespace = namespace
+    }
+}
+
 public struct ExportedFunction: Codable, Equatable, Sendable {
     public var name: String
     public var abiName: String
@@ -407,12 +420,20 @@ public struct ExportedSkeleton: Codable {
     public let functions: [ExportedFunction]
     public let classes: [ExportedClass]
     public let enums: [ExportedEnum]
+    public let protocols: [ExportedProtocol]
 
-    public init(moduleName: String, functions: [ExportedFunction], classes: [ExportedClass], enums: [ExportedEnum]) {
+    public init(
+        moduleName: String,
+        functions: [ExportedFunction],
+        classes: [ExportedClass],
+        enums: [ExportedEnum],
+        protocols: [ExportedProtocol] = []
+    ) {
         self.moduleName = moduleName
         self.functions = functions
         self.classes = classes
         self.enums = enums
+        self.protocols = protocols
     }
 }
 
@@ -514,6 +535,9 @@ extension BridgeType {
             return nil
         case .namespaceEnum:
             return nil
+        case .swiftProtocol:
+            // Protocols pass JSObject IDs as Int32
+            return .i32
         }
     }
 

Plugins/BridgeJS/Sources/BridgeJSSkeleton/BridgeJSSkeleton.swift

@@ -0,0 +1,41 @@
+import JavaScriptKit
+
+@JS protocol MyViewControllerDelegate {
+    func onSomethingHappened()
+    func onValueChanged(_ value: String)
+    func onCountUpdated(count: Int) -> Bool
+    func onLabelUpdated(_ prefix: String, _ suffix: String)
+    func isCountEven() -> Bool
+}
+
+@JS class MyViewController {
+    @JS
+    var delegate: MyViewControllerDelegate
+
+    @JS
+    var secondDelegate: MyViewControllerDelegate?
+
+    @JS init(delegate: MyViewControllerDelegate) {
+        self.delegate = delegate
+    }
+
+    @JS func triggerEvent() {
+        delegate.onSomethingHappened()
+    }
+
+    @JS func updateValue(_ value: String) {
+        delegate.onValueChanged(value)
+    }
+
+    @JS func updateCount(_ count: Int) -> Bool {
+        return delegate.onCountUpdated(count: count)
+    }
+
+    @JS func updateLabel(_ prefix: String, _ suffix: String) {
+        delegate.onLabelUpdated(prefix, suffix)
+    }
+
+    @JS func checkEvenCount() -> Bool {
+        return delegate.isCountEven()
+    }
+}

Plugins/BridgeJS/Tests/BridgeJSToolTests/Inputs/Protocol.swift

@@ -0,0 +1,44 @@
+// NOTICE: This is auto-generated code by BridgeJS from JavaScriptKit,
+// DO NOT EDIT.
+//
+// To update this file, just rebuild your project or run
+// `swift package bridge-js`.
+
+export interface MyViewControllerDelegate {
+    onSomethingHappened(): void;
+    onValueChanged(value: string): void;
+    onCountUpdated(count: number): boolean;
+    onLabelUpdated(prefix: string, suffix: string): void;
+    isCountEven(): boolean;
+}
+
+/// Represents a Swift heap object like a class instance or an actor instance.
+export interface SwiftHeapObject {
+    /// Release the heap object.
+    ///
+    /// Note: Calling this method will release the heap object and it will no longer be accessible.
+    release(): void;
+}
+export interface MyViewController extends SwiftHeapObject {
+    triggerEvent(): void;
+    updateValue(value: string): void;
+    updateCount(count: number): boolean;
+    updateLabel(prefix: string, suffix: string): void;
+    checkEvenCount(): boolean;
+    delegate: MyViewControllerDelegate;
+    secondDelegate: MyViewControllerDelegate | null;
+}
+export type Exports = {
+    MyViewController: {
+        new(delegate: MyViewControllerDelegate): MyViewController;
+    }
+}
+export type Imports = {
+}
+export function createInstantiator(options: {
+    imports: Imports;
+}, swift: any): Promise<{
+    addImports: (importObject: WebAssembly.Imports) => void;
+    setInstance: (instance: WebAssembly.Instance) => void;
+    createExports: (instance: WebAssembly.Instance) => Exports;
+}>;