refactor: define DOMException in Rust

[littledivy]

No description provided.

[Copilot]

Pull Request Overview

This PR migrates the DOMException implementation from JavaScript to Rust using the cppgc (C++ garbage collection) API. The goal is to improve performance by moving the core implementation to native code while maintaining compatibility with the existing JavaScript API.

• Moved DOMException struct and implementation to Rust using deno_core::cppgc
• Implemented native constructor and getters for message, name, and code properties
• Removed JavaScript class implementation in favor of prototype extensions

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 4 comments.

File	Description
ext/web/lib.rs	Added DOMException struct with cppgc implementation, constructor, and getters; registered as extension object
ext/web/01_dom_exception.js	Removed JavaScript class implementation; imported native DOMException and added custom inspect method to prototype

Comments suppressed due to low confidence (1)

ext/web/01_dom_exception.js:28

• These symbol constants are no longer used after migrating to the Rust implementation. They should be removed to avoid dead code.

const _name = Symbol("name");
const _message = Symbol("message");
const _code = Symbol("code");

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[Copilot]

The args parameter is declared but never used in the constructor function. If this parameter is not needed for the implementation, it should be removed. If it's intended for future use or required by the macro, consider adding a comment explaining its purpose.

Suggested change

#[varargs] args: Option<&v8::FunctionCallbackArguments>,

[Copilot]

The constant DOMSTRING_SIZE_ERR = 2 is missing from the Rust implementation but is present in the JavaScript constants (line 33 of 01_dom_exception.js). This inconsistency could lead to issues if this error code is needed.

Suggested change

	const INDEX_SIZE_ERR: u32 = 1;
	const INDEX_SIZE_ERR: u32 = 1;
	const DOMSTRING_SIZE_ERR: u32 = 2;

[Copilot]

The constant NO_DATA_ALLOWED_ERR = 6 is missing from the Rust implementation but is present in the JavaScript constants (line 37 of 01_dom_exception.js). This inconsistency could lead to issues if this error code is needed.

Suggested change

	const INVALID_CHARACTER_ERR: u32 = 5;
	const INVALID_CHARACTER_ERR: u32 = 5;
	const NO_DATA_ALLOWED_ERR: u32 = 6;

[littledivy]

brocacho its unused in rust

[Copilot]

The constant VALIDATION_ERR = 16 is missing from the Rust implementation but is present in the JavaScript constants (line 47 of 01_dom_exception.js). This inconsistency could lead to issues if this error code is needed.

[littledivy]

ditto