Method constructor

src/type-extensions/proxy.ts:22–125

(thread: Global)

    private readonly gcPointer: number

    public constructor(thread: Global) {
        super(thread, 'js_proxy')

        this.gcPointer = thread.lua.module.addFunction((functionStateAddress: LuaState) => {
            // Throws a lua error which does a jump if it does not match.
            const userDataPointer = thread.lua.luaL_checkudata(functionStateAddress, 1, this.name)
            const referencePointer = thread.lua.module.getValue(userDataPointer, '*')
            thread.lua.unref(referencePointer)

            return LuaReturn.Ok
        }, 'ii')

        if (thread.lua.luaL_newmetatable(thread.address, this.name)) {
            const metatableIndex = thread.lua.lua_gettop(thread.address)

            // Mark it as uneditable
            thread.lua.lua_pushstring(thread.address, 'protected metatable')
            thread.lua.lua_setfield(thread.address, metatableIndex, '__metatable')

            // Add the gc function
            thread.lua.lua_pushcclosure(thread.address, this.gcPointer, 0)
            thread.lua.lua_setfield(thread.address, metatableIndex, '__gc')

            thread.pushValue((self: any, key: unknown) => {
                switch (typeof key) {
                    case 'number':
                        // Map from Lua's 1 based indexing to JS's 0.
                        // This is especially important here because ipairs just calls
                        // __index with 1, 2, 3, 4 etc until there's a null.
                        key = key - 1
                    // Fallthrough
                    case 'string':
                        break
                    default:
                        throw new Error('Only strings or numbers can index js objects')
                }

                const value = self[key as string | number]
                if (typeof value === 'function') {
                    return decorateFunction(value as (...args: any[]) => any, { self })
                }

                return value
            })
            thread.lua.lua_setfield(thread.address, metatableIndex, '__index')

            thread.pushValue((self: any, key: unknown, value: any) => {
                switch (typeof key) {
                    case 'number':
                        // Map from Lua's 1 based indexing to JS's 0.
                        key = key - 1
                    // Fallthrough
                    case 'string':
                        break
                    default:
                        throw new Error('Only strings or numbers can index js objects')
                }
                self[key as string | number] = value