Router only checks that `window.history.state` isn't empty, breaks when used with other frameworks

[ariel-codes]

Versions:

• @inertiajs/core version: 1.2.0
• @inertiajs/vue2 version: #.#.#
• @inertiajs/vue3 version: #.#.#
• @inertiajs/react version: 1.2.0
• @inertiajs/svelte version: #.#.#

Describe the problem:

When navigating back/forward from pages, the router only checks that window.history.state is not empty, but this can conflict with other navigation frameworks (in my case Turbo/Hotwire, which uses window.history.state.turbo). This in turn leads to the resolve function passed to createInertiaApp being called with an undefined arg.

Steps to reproduce:

• Set window.history.state to any truthy value before initializing Inertia

[pedroborges]

@ariel-codes I'm curious about how you're integrating Inertia.js with Turbo/Hotwire, as they generally aim to solve similar problems but in different ways. It's my understanding that Turbo drives navigation and partial updates without the need for a front-end framework, while Inertia integrates tightly with frameworks like Vue, React, and Svelte.

Since both manipulate the history.state, it's understandable that there would be conflicts in scenarios where both are being used. As for Inertia, we might need a safeguard to confirm the presence of Inertia-specific data in history.state before continuing execution.

[pascalbaljet]

For reference, see also PR #2238. I don't think we'll support other frameworks/libraries interfering with the history state.