Jsimgui Crash: Command Key Issue On Mac Chrome

by Luna Greco 47 views

Hey everyone! We've got a tricky issue to dive into today – a crashing bug that some users are encountering when pressing the Command key on their Macs while using Chrome with jsimgui. Let's break down the problem, explore the error message, and figure out what might be going on.

Understanding the Crash

So, the core issue is that when users hit either the left or right Command key in Chrome on their Macbook while running an application using jsimgui, they're seeing a crash. This is obviously a major pain point, as the Command key is pretty essential for a lot of common actions. The crash manifests as a TypeError, specifically: Cannot convert "undefined" to int. This type of error usually indicates that the code is trying to treat something that isn't a number (in this case, undefined) as if it were an integer.

This TypeError originates from within the jsimgui library itself, pinpointed to the toWireType function within the jsimgui-webgl2-tt.js file. Diving deeper into the stack trace, we see the error bubbling up through a series of calls related to handling keyboard events. The trail leads from ImGuiIO.ImGuiIO_AddKeyEvent to ImGuiIO.AddKeyEvent and finally to handleKeyboardEvent, before culminating in the event listener attached to the HTMLCanvasElement. It looks like the handleKeyboardEvent function within jsimgui is the primary suspect here. The function is likely attempting to process the key event associated with the Command key, but it encounters an undefined value when trying to convert it to an integer, leading to the crash. This suggests that some part of the key event data is not being properly populated or is not in the expected format when the Command key is pressed. It is also essential to consider browser-specific behaviors. Different browsers may handle key events in slightly different ways, which could explain why this issue is occurring specifically in Chrome. The way Chrome interprets and passes the key code or modifiers for the Command key might be different from other browsers, leading to the undefined value being passed to the toWireType function. Furthermore, the problem might be triggered by a combination of factors, such as the specific version of Chrome being used, the operating system (macOS), and the version of jsimgui. Certain versions might have compatibility issues that cause this error to surface.

Decoding the Error Message

Let's dissect the error message piece by piece:

Cannot convert "undefined" to int
TypeError: Cannot convert "undefined" to int
    at Object.toWireType (webpack-internal:///./node_modules/.pnpm/@[email protected]/node_modules/@mori2003/jsimgui/build/jsimgui-webgl2-tt.js:4293:27)
    at ImGuiIO.ImGuiIO_AddKeyEvent (eval at createJsInvoker (webpack-internal:///./node_modules/.pnpm/@[email protected]/node_modules/@mori2003/jsimgui/build/jsimgui-webgl2-tt.js), <anonymous>:7:17)
    at ImGuiIO.AddKeyEvent (webpack-internal:///./node_modules/.pnpm/@[email protected]/node_modules/@mori2003/jsimgui/build/mod.js:1315:26)
    at handleKeyboardEvent (webpack-internal:///./node_modules/.pnpm/@[email protected]/node_modules/@mori2003/jsimgui/build/mod.js:4708:8)
    at HTMLCanvasElement.eval (webpack-internal:///./node_modules/.pnpm/@[email protected]/node_modules/@mori2003/jsimgui/build/mod.js:4771:47)
  • **`Cannot convert