To allow implementing the DOM class hierarchy in JS bindings, this
patch adds an inherits() function that can be used to ask an Object
if it inherits from a specific C++ class (by name).
The necessary overrides are baked into each Object subclass by the
new JS_OBJECT macro, which works similarly to C_OBJECT in LibCore.
Thanks to @Dexesttp for suggesting this approach. :^)
More work towards supporting multiple global objects. Native C++ code
now get a GlobalObject& and don't have to ask the Interpreter for it.
I've added macros for declaring and defining native callbacks since
this was pretty tedious and this makes it easier next time we want to
change any of these signatures.
A ConsoleMessage is a struct cointaining:
* AK::String text; represents the text of the message sent
to the console.
* ConsoleMessageKind kind; represents the kind of JS `console` function
from which the message was sent.
Now, Javascript `console` functions only send a ConsoleMessage to the
Interpreter's Console instead of printing text directly to stdout.
The Console then stores the recived ConsoleMessage in
Console::m_messages; the Console does not print to stdout by default.
You can set Console::on_new_message to a void(ConsoleMessage&); this
function will get call everytime a new message is added to the Console's
messages and can be used, for example, to print ConsoleMessages to
stdout or to color the output based on the kind of ConsoleMessage.
In this patch, I also:
* Re-implement all the previously implemented functions in the
JavaScript ConsoleObject, as wrappers around Console functions
that add new message to the Console.
* Implement console.clear() like so:
- m_messages get cleared;
- a new_message with kind set ConsoleMessageKind::Clear gets added
to m_messages, its text is an empty AK::String;
* Give credit to linusg in Console.cpp since I used his
console.trace() algorithm in Console::trace().
I think that having this abstration will help us in the implementation
of a browser console or a JS debugger. We could also add more MetaData
to ConsoleMessage, e.g. Object IDs of the arguments passed to console
functions in order to make hyperlinks, Timestamps, ecc.; which could be
interesting to see.
This will also help in implementing a `/bin/js` option to make, for
example, return a ConsoleMessageWrapper to console functions instead of
undefined. This will be useful to make tests for functions like
console.count() and console.countClear(). :^)
Instead of implementing every native function as a lambda function,
use static member functions instead.
This makes it easier to navigate the code + backtraces look nicer. :^)