From 7ceb30bdf17534b38369c174ce8373bf8e3e52d2 Mon Sep 17 00:00:00 2001
From: iddev5 <ayushbardhan5@gmail.com>
Date: Thu, 7 Jul 2022 18:33:29 +0530
Subject: [PATCH] js-runtime: Add constructor calling capability (new operator
 on Js types)

---
 js-runtime/src/js-runtime.js | 11 +++++++++++
 js-runtime/src/main.zig      | 14 ++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/js-runtime/src/js-runtime.js b/js-runtime/src/js-runtime.js
index c71184b5..4d1ae9ff 100644
--- a/js-runtime/src/js-runtime.js
+++ b/js-runtime/src/js-runtime.js
@@ -308,6 +308,17 @@ const zig = {
     zig.functionCall(values[id], undefined, args, args_len, ret_ptr);
   },
 
+  zigConstructType(id, args, args_len, ret_ptr) {
+    let memory = new MemoryBlock(zig.wasm.exports.memory.buffer);
+    let argv = [];
+    for (let i = 0; i < args_len; i += 1) {
+      argv.push(zig.readObject(memory.slice(args + i * 16), memory));
+    }
+
+    const result = zig.addValue(new values[id](argv));
+    zig.writeObject(memory.slice(ret_ptr), result, 0);
+  },
+
   wzLogWrite(str, len) {
     let memory = new MemoryBlock(zig.wasm.exports.memory.buffer);
     log_buf += memory.getString(str, len);
diff --git a/js-runtime/src/main.zig b/js-runtime/src/main.zig
index b84f911d..d584d6be 100644
--- a/js-runtime/src/main.zig
+++ b/js-runtime/src/main.zig
@@ -17,6 +17,7 @@ const js = struct {
     extern fn zigDeleteIndex(id: u64, index: u32) void;
     extern fn zigFunctionCall(id: u64, name: [*]const u8, len: u32, args: ?*const anyopaque, args_len: u32, ret_ptr: *anyopaque) void;
     extern fn zigFunctionInvoke(id: u64, args: ?*const anyopaque, args_len: u32, ret_ptr: *anyopaque) void;
+    extern fn zigConstructType(id: u64, args: ?*const anyopaque, args_len: u32, ret_ptr: *anyopaque) void;
     extern fn zigCleanupObject(id: u64) void;
 };
 
@@ -142,6 +143,12 @@ pub const Function = struct {
         return .{ .tag = .func_zig, .val = .{ .ref = func.ref } };
     }
 
+    pub fn construct(func: *const Function, args: []const Value) Value {
+        var ret: Value = undefined;
+        js.zigConstructType(func.ref, args.ptr, args.len, &ret);
+        return ret;
+    }
+
     pub fn invoke(func: *const Function, args: []const Value) Value {
         var ret: Value = undefined;
         js.zigFunctionInvoke(func.ref, args.ptr, args.len, &ret);
@@ -202,3 +209,10 @@ pub fn createFunction(fun: FunType) Function {
     }
     return .{ .ref = js.zigCreateFunction(&fun) };
 }
+
+pub fn constructType(t: []const u8, args: []const Value) Value {
+    const constructor = global().get(t).value(.func, null);
+    defer constructor.deinit();
+
+    return constructor.construct(args);
+}