Bug 288832 – [JSC] `RegExp#[Symbol.search]` should throw `TypeError` when `lastIndex` isn't writable

• Status: RESOLVED
• Resolution: FIXED
• Component: JavaScriptCore

[Sosuke Suzuki]

According to the spec[1], `RegExp#[Symbol.search]`
    writes to the `lastIndex` property of `this` in
    the following cases:
    
    - `lastIndex` is not 0
    - The value of `lastIndex` changes before and after
      calling `RegExpExec` (which occurs when the `g`
      or `y` flag is enabled)
    
    So, if `lastIndex` is not writable and the above
    conditions are met, a `TypeError` should be thrown.
    
    However, in the current JSC implementation, no error
    is thrown. This patch changes to execute the slow
    path when `lastIndex` is not writable, ensuring that
    an error is thrown.

 [1]: https://tc39.es/ecma262/#sec-regexp.prototype-%symbol.search%

[Sosuke Suzuki]

Pull request: https://github.com/WebKit/WebKit/pull/41631

[Radar WebKit Bug Importer]

<rdar://problem/146488846>

[Sosuke Suzuki]

Pull request: https://github.com/WebKit/WebKit/pull/42660

[EWS]

Committed 296443@main (8657eef539f3): <https://commits.webkit.org/296443@main>

Reviewed commits have been landed. Closing PR #42660 and removing active labels.