[bug] Cancelling drag & drop with the escape key does not fire cancellation

[keehun]

Describe the bug

When I am in the middle of a drag & drop operation (dragging in a file outside of the app into the app), if I click the Escape key to cancel the drag & drop before I actually drop the file, the onDragDropEvent() handler will not get an event for that cancellation.

See this console log output as an example:

The first line shows my onDragDropEvent() handler registering the dragged event. The second line appears when I click the Escape key.

The referenced line in the stack trace, webview.js:481 is the following:

I wonder if position should allowed to be null/undefined and/or always report the last-known point if unknown.

P.S. I only tested this on macOS, but I imagine that behavior would be similar on Windows and Linux?

Reproduction

1. Set up a very basic Tauri app with:

import { getCurrent } from "@tauri-apps/api/webview";
<...>
await getCurrent().onDragDropEvent((event) => {
    console.log(event)
}

2. Drag in a file. Notice the initial drag-on event firing.
3. Before dropping the file, press the Escape key to cancel the drag & drop.

Expected behavior

Another event should fire with the cancellation information.

Full tauri info output

$ tauri info

[✔] Environment
    - OS: Mac OS 14.4.0 X64
    ✔ Xcode Command Line Tools: installed
    ✔ rustc: 1.79.0 (129f3b996 2024-06-10)
    ✔ cargo: 1.79.0 (ffa9cf99a 2024-06-03)
    ✔ rustup: 1.27.1 (54dd3d00f 2024-04-24)
    ✔ Rust toolchain: stable-aarch64-apple-darwin (default)
    - node: 21.5.0
    - npm: 10.2.4
    - bun: 1.1.15

[-] Packages
    - tauri [RUST]: 2.0.0-beta.22
    - tauri-build [RUST]: 2.0.0-beta.17
    - wry [RUST]: 0.40.1
    - tao [RUST]: 0.28.1
    - @tauri-apps/api : not installed!
    - @tauri-apps/cli [NPM]: 2.0.0-beta.20

[-] App
    - build-type: bundle
    - CSP: unset
    - frontendDist: ../build
    - devUrl: http://localhost:1420/
    - framework: Svelte
    - bundler: Vite

Stack trace

[Error] TypeError: null is not an object (evaluating 'event.payload.position')
	(anonymous function) (webview.js:481)
	value (user-script:5:227)
	value (user-script:5:299)
	(anonymous function) (Script Element 16:1:91)
	Global Code (Script Element 16:1:173)

Additional context

No response