breaking: deprecate error(status, {...}) in favour of error(status, message, {...})

[Rich-Harris]

The TODO from #16162 (comment) — error(status, {...}) is now deprecated in favour of passing any additional properties as the third argument

---

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[pkg-svelte-dev]

Install the latest version of @sveltejs/kit from 5d85e6c:

pnpm add https://pkg.svelte.dev/@sveltejs/kit/c/5d85e6c4b6575055db0f8a9aca33d4cb2e887c2d

Open in pkg.svelte.dev: https://pkg.svelte.dev/repos/kit/pr/16540

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🦋 Changeset detected

Latest commit: 5d85e6c

The changes in this PR will be included in the next version bump.

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-kit-16540-svelte.vercel.app/

[WarningImHack3r]

With the following App.Error:

declare global {
	namespace App {
		interface Error {
			/**
			 * A description, going in pair with a custom message.
			 * When provided, the error code is shown much more subtly
			 * and the description is shown where the title used to be.
			 */
			description?: string;
			/**
			 * Additional links to suggest going to in a button on the error page.
			 * Internal links must be `resolve`d for safety purposes, while
			 * external links can also be provided.
			 */
			links?: {
				text: string;
				href: ResolvedPathname | `https://${string}`;
			}[];
		}
	}
}

The deprecated error signature I used to use was:

error(status: number, body: Omit<App.Error, "status"> & {
    status?: App.Error["status"];
}): never

Like this:

error(400, {
	message: "...",
	description: "...",
	links: [/*...*/]
});

But now, when using the new format:

error(400, "...", {
	description: "...",
	links: [/*...*/]
});

It says the third parameter is not assignable to never, matching:

error(status: number, message?: string | undefined): never

With this error:

No overload matches this call. Overload 1 of 6,
(status: number, body: string, properties: never): never
, gave the following error. Argument of type
{ description: string; links: { text: string; href: string; }[]; }
is not assignable to parameter of type never. Overload 2 of 6,
(status: number, message: string, properties: never): never
, gave the following error. Argument of type
{ description: string; links: { text: string; href: string; }[]; }
is not assignable to parameter of type never. (ts 2769)

Presumably because my App.Error doesn't contain a status & message?

[teemingc]

Presumably because my App.Error doesn't contain a status & message?

No, excluding those seems correct. Seems more like something stale is lingering or tsconfig is not configured correctly. If you can reproduce this on a fresh kit 3 project, you should file an issue with the minimal reproduction.