Previously we would treat the empty string as `null`. This caused
JavaScript like this to fail:
```js
var object = {};
try {
object = JSON.parse("");
} catch {}
var array = object.array || [];
```
Since `JSON.parse("")` returned null instead of throwing, it would set
`object` to null and then try and use it instead of using the default
backup value.
Parse JSON floating point literals properly,
No longer throwing a SyntaxError when the decimal portion
of the number exceeds the capacity of u32.
Added tests to AK/TestJSON and LibJS/builtins/JSON/JSON.parse
This unbreaks the /var/run/utmp system which starts out as an empty
string, and is then turned into an object by the first update.
This isn't necessarily the best way for this to work, but it's how
it used to work, so this just fixes the regression for now.
Also add slightly richer parse errors now that we can include a string
literal with returned errors.
This will allow us to use TRY() when working with JSON data.
The following commit broke Tests/AK/TestJSON.cpp as it removed the
file that the test loaded from disk to validate JSON parsing.
commit ad141a2286
Author: Andreas Kling <kling@serenityos.org>
Date: Sat Jul 31 15:26:14 2021 +0200
Base: Remove "test.frm" from HackStudio test project
Instead of restoring the file, lets just embed a bit of JSON in the
test case to avoid using external resources, as they obviously are
surprising and make the test less portable across environments.
Prior to this, it'd try to stuff them into an i64, which could fail and
give us nothing.
Even though this is an extension we've made to JSON, the parser should
be able to correctly round-trip from whatever our serialiser has
generated.
