Defaults lsp-ui-peek-expand-function to unfold all xref items

[MaskRay]

It currently displays xref items in the current buffer and folds others. I use (setq lsp-ui-peek-expand-function (lambda (xs) (mapcar #'car xs))) to unfold all files. I wonder if this is a better default to unfold all xref items.

C/C++ has separated header files and .c/.cc/.cpp/.cxx/.... Finding references in C/C++ a.h will likely reveal references in a.cc.

[sebastiencs]

I really think it's a bad idea.
The issue is, in case there are a lot of files, it would make open them all, which can take a lot of time and unnecessary ressources.
vscode doesn't unfold items in its peek view too.

You can change that behavior with lsp-ui-peek-expand-function but I think the default should be keep as it is now.

[MaskRay]

Then provide (lambda (xs) (mapcar #'car xs)) as an alternative expand-function?

Anternatively, if the number of xref items is smaller than a threshold, unfold all?

[sebastiencs]

The variable lsp-ui-peek-expand-function has been created specifically for this purpose: #8.
The user is free to choose whatever behavior he wants