Bug 189947 – [JSC] Merge node-jsc Webkit changes upstream

• Status: NEW
• Component: JavaScriptCore

[Koby]

Hi, I'm Koby Boyango, the authro of node-jsc, a node.js fork to JavaScriptCore and iOS.
Currently, as I needed to make some changes in WebKit, I have my own fork (https://github.com/mceSystems/webkit).

I would love to offer the changes I've made to WebKit, and hopefully merge as much as possible upstream. The changes are mainly around JavaScriptCore, WTF and building the JSCOnly port with cmake. Following the discussion on the webkit-dev mailiing list:
https://lists.webkit.org/pipermail/webkit-dev/2018-September/030140.html
I'm creating this "umbrella" bug, and I'll create a new (blocking) bug for each patch.

This is the first time I'm working with WebKit and try to send patches, so please let me know if i'm not doing something correctly with the patches.

Koby

[Yusuke Suzuki]

(In reply to Koby from comment #0)
> Hi, I'm Koby Boyango, the authro of node-jsc, a node.js fork to
> JavaScriptCore and iOS.
> Currently, as I needed to make some changes in WebKit, I have my own fork
> (https://github.com/mceSystems/webkit).
> 
> I would love to offer the changes I've made to WebKit, and hopefully merge
> as much as possible upstream. The changes are mainly around JavaScriptCore,
> WTF and building the JSCOnly port with cmake. Following the discussion on
> the webkit-dev mailiing list:
> https://lists.webkit.org/pipermail/webkit-dev/2018-September/030140.html
> I'm creating this "umbrella" bug, and I'll create a new (blocking) bug for
> each patch.
> 
> This is the first time I'm working with WebKit and try to send patches, so
> please let me know if i'm not doing something correctly with the patches.
> 
> Koby

Reading https://github.com/mceSystems/node-jsc/blob/master/deps/jscshim/docs/webkit_fork_and_compilation.md document, and I have one suggestion.

> Added CustomAPIValue: Similar in functionality to v8's accessor (and used to implement them), allowing object properties that appear like data properties, but invoke native callbacks when accessed.

JavaScriptCore has a similar functionality, called, CustomValue. While CustomAccessor in JSC looks as an accessor, CustomValue looks like a value, but it invokes a function.
Let's look at RegExpConstructor.cpp's regExpConstructorInput etc. They are values. But they invoke corresponding functions to produce returned values.
You can leverage CustomValue mechanism to implement it I think.

[Koby]

Thanks for taking the time read node-jsc's docs!
When I wanted to implement the accessors api I looked into CustomValue and it didn't seem like I could use it, so I ended up implementing (the similarly, and badly, named) CustomAPIValue. I'll create a bug for it and explain more, but I'll take another look at CustomValue.