On 30/11/2021 23:20, Jacek Caban wrote:
On 11/29/21 5:31 PM, Gabriel Ivăncescu wrote:
+ else if(function->proc == Object_toString && ctx->version >= SCRIPTLANGUAGEVERSION_ES5) { + jsstr_t *ret; + if(!r) + return S_OK; + ret = jsstr_alloc(L"[object Null]"); + if(!ret) + return E_OUTOFMEMORY; + *r = jsval_string(ret); + return S_OK; + }
This is ugly. I think that what you observe is a change in how ES5 treats 'this' argument in builtin functions. It allows 'this' to be of any type for builtin function. The conversion to object (or using a global object in place of null) happens only when we enter JS function, if I read it right. To support this properly, I'm afraid that we'd need to pass 'this' as jsval to builtin functions. We wouldn't need any special casing for toString() then.
Interesting, I did not realize builtin functions were special in regards to the "this" context. I'll send this separately later then, but passing jsval to builtin functions would also help with fixing the undefined case (since toString reports [object Undefined] then), so it's on the right track for sure.