Implement Closure release method

Author: kateinoigakukun

IntegrationTests/JavaScriptKitExec/Sources/JavaScriptKitExec/main.swift

@@ -184,7 +184,7 @@ Host_Function_Registration: do {
     let prop_6Ref = try expectObject(prop_6)
 
     var isHostFunc1Called = false
-    let hostFunc1 = JSFunctionRef.from { (arguments) -> JSValue in
+    let hostFunc1 = JSClosure { (arguments) -> JSValue in
         isHostFunc1Called = true
         return .number(1)
     }
@@ -196,7 +196,9 @@ Host_Function_Registration: do {
     try expectEqual(call_host_1Func(), .number(1))
     try expectEqual(isHostFunc1Called, true)
 
-    let hostFunc2 = JSFunctionRef.from { (arguments) -> JSValue in
+    hostFunc1.release()
+
+    let hostFunc2 = JSClosure { (arguments) -> JSValue in
         do {
             let input = try expectNumber(arguments[0])
             return .number(input * 2)
@@ -207,7 +209,7 @@ Host_Function_Registration: do {
 
     try expectEqual(hostFunc2(3), .number(6))
     _ = try expectString(hostFunc2(true))
-
+    hostFunc2.release()
 } catch {
     print(error)
 }

Sources/JavaScriptKit/JSFunction.swift

@@ -54,21 +54,40 @@ public class JSFunctionRef: JSObjectRef {
         }
     }
 
-    static var sharedFunctions: [([JSValue]) -> JSValue] = []
+    @available(*, unavailable, message: "Please use JSClosure instead")
     public static func from(_ body: @escaping ([JSValue]) -> JSValue) -> JSFunctionRef {
-        let id = JavaScriptHostFuncRef(sharedFunctions.count)
-        sharedFunctions.append(body)
-        var funcRef: JavaScriptObjectRef = 0
-        _create_function(id, &funcRef)
-
-        return JSFunctionRef(id: funcRef)
+        fatalError("unavailable")
     }
 
     public override func jsValue() -> JSValue {
         .function(self)
     }
 }
 
+public class JSClosure: JSFunctionRef {
+
+    static var sharedFunctions: [JavaScriptHostFuncRef: ([JSValue]) -> JSValue] = [:]
+
+    private var hostFuncRef: JavaScriptHostFuncRef = 0
+
+    public init(_ body: @escaping ([JSValue]) -> JSValue) {
+        super.init(id: 0)
+        let objectId = ObjectIdentifier(self)
+        let funcRef = JavaScriptHostFuncRef(bitPattern: Int32(objectId.hashValue))
+        Self.sharedFunctions[funcRef] = body
+
+        var objectRef: JavaScriptObjectRef = 0
+        _create_function(funcRef, &objectRef)
+
+        self.hostFuncRef = funcRef
+        self.id = objectRef
+    }
+
+    public func release() {
+        Self.sharedFunctions[hostFuncRef] = nil
+    }
+}
+
 
 @_cdecl("swjs_prepare_host_function_call")
 public func _prepare_host_function_call(_ argc: Int32) -> UnsafeMutableRawPointer {
@@ -86,7 +105,9 @@ public func _call_host_function(
     _ hostFuncRef: JavaScriptHostFuncRef,
     _ argv: UnsafePointer<RawJSValue>, _ argc: Int32,
     _ callbackFuncRef: JavaScriptObjectRef) {
-    let hostFunc = JSFunctionRef.sharedFunctions[Int(hostFuncRef)]
+    guard let hostFunc = JSClosure.sharedFunctions[hostFuncRef] else {
+        fatalError("The function was already released")
+    }
     let args = UnsafeBufferPointer(start: argv, count: Int(argc)).map {
         $0.jsValue()
     }

Sources/JavaScriptKit/JSObject.swift

@@ -2,7 +2,7 @@ import _CJavaScriptKit
 
 @dynamicMemberLookup
 public class JSObjectRef: Equatable {
-    let id: UInt32
+    internal var id: UInt32
     init(id: UInt32) {
         self.id = id
     }

Sources/JavaScriptKit/JSValue.swift

@@ -49,7 +49,7 @@ public enum JSValue: Equatable {
 
 extension JSValue {
     public static func function(_ body: @escaping ([JSValue]) -> JSValue) -> JSValue {
-        .function(JSFunctionRef.from(body))
+        .function(JSClosure(body))
     }
 }