From 3b00b478ced7a175c8f7799f58e266bef2cdc63d Mon Sep 17 00:00:00 2001
From: iddev5 <ayushbardhan5@gmail.com>
Date: Thu, 7 Jul 2022 23:55:32 +0530
Subject: [PATCH] js: Implement Value.instanceOf method which performs Js'
 ``instanceof`` check

---
 js-runtime/src/js-runtime.js | 7 +++++++
 js-runtime/src/main.zig      | 5 +++++
 2 files changed, 12 insertions(+)

diff --git a/js-runtime/src/js-runtime.js b/js-runtime/src/js-runtime.js
index 0dd61fed..8bca277a 100644
--- a/js-runtime/src/js-runtime.js
+++ b/js-runtime/src/js-runtime.js
@@ -276,6 +276,13 @@ const zig = {
     return val_js === other_js;
   },
 
+  zigValueInstanceOf(val, other) {
+    let memory = new MemoryBlock(zig.wasm.exports.memory.buffer);
+    const val_js = zig.readObject(memory.slice(val), memory);
+    const other_js = zig.readObject(memory.slice(other), memory);
+    return val_js instanceof other_js;
+  },
+
   functionCall(func, this_param, args, args_len, ret_ptr) {
     let memory = new MemoryBlock(zig.wasm.exports.memory.buffer);
     let argv = [];
diff --git a/js-runtime/src/main.zig b/js-runtime/src/main.zig
index 53d75ad4..1d8f7045 100644
--- a/js-runtime/src/main.zig
+++ b/js-runtime/src/main.zig
@@ -15,6 +15,7 @@ const js = struct {
     extern fn zigGetString(val_id: u64, ptr: [*]const u8) void;
     extern fn zigGetStringLength(val_id: u64) u32;
     extern fn zigValueEqual(val: *const anyopaque, other: *const anyopaque) bool;
+    extern fn zigValueInstanceOf(val: *const anyopaque, other: *const anyopaque) bool;
     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;
@@ -92,6 +93,10 @@ pub const Value = extern struct {
             else => js.zigValueEqual(val, &other),
         };
     }
+
+    pub fn instanceOf(val: *const Value, other: Value) bool {
+        return js.zigValueInstanceOf(val, &other);
+    }
 };
 
 pub const Object = struct {