'CUT' not work in context menu

[shuyaqian]

Bug Description:

Steps to Reproduce:

1. select something
2. click Edit—>Cut
3. cut not work

Additional Information

• Operating System: linux
• Theia Version: 1.19.0

[msujew]

@shuyaqian I am not able to reproduce this issue on the current master. Do you mind retesting it there?

[colin-grant-work]

I believe it's a similar issue to #10540. Basically, it goes back to #9830: that PR introduced conditions under which what was formerly not a context menu got to be rendered as a context menu. That means that commands that formerly didn't receive the default Anchor argument associated with context menus are now receiving it, and since command handlers receive any[] as their args and so can assert that they'll receive what they want without checking, very few commands have effective type checking.

There are a few options:

• Remove the anchor argument for all context menus, as fix default Anchor param of context menu #10540 originally tried to do.
• Implement type checks, as we've encouraged in fix default Anchor param of context menu #10540
• Change the rendering strategy for the menu when window.menuBarVisibility is set to compact so that it does not behave like a context menu and pass the anchor argument as the default.

I think the last is actually the correct move: it isn't really a context menu, and it shouldn't behave like one. That would fix all affected handlers without our having to identify them one by one. I think the utilities in browser-menu-plugin.ts can be of use here, but it will take a bit of fiddling.

[colin-grant-work]

With a bit of checking, this turns out not to have to do with the context menu anchor issue at all, but with a failure of the menu-opening machinery of the new compact menu widget to restore focus to the previous context when the user makes a selection. Then, since the context is not the text input, the cut command has no effect.