testDirectProxyKeys4.js (285B)
1 load(libdir + "asserts.js"); 2 3 // Throw TypeError if trap returns a property key multiple times. 4 5 var handler = { ownKeys: () => [ 'foo', 'foo' ] }; 6 for (let p of [new Proxy({}, handler), Proxy.revocable({}, handler).proxy]) 7 assertThrowsInstanceOf(() => Object.keys(p), TypeError);