JSTests/es6/Proxy_internal_get_calls_ToPrimitive.js

function test() {

// ToPrimitive -> Get -> [[Get]]
var get = [];
var p = new Proxy({toString:Function()}, { get: function(o, k) { get.push(k); return o[k]; }});
p + 3;
return get[0] === Symbol.toPrimitive && get.slice(1) + '' === "valueOf,toString";
      
}

if (!test())
    throw new Error("Test failed");