bug#72203: 31.0.50; browse-url-emacs (url-file-handler) errors when eglot is loaded

[Dmitry Gutov]

On 20/07/2024 03:56, Nick OBrien via Bug reports for GNU Emacs, the 
Swiss army knife of text editors wrote:
>        nil(...)
>        url-directory-files("https://www.gnu.org/licenses/";  nil ... t nil)
>        apply(url-directory-files ("https://www.gnu.org/licenses/";  nil ... t 
> nil))
>        url-file-handler(directory-files"https://www.gnu.org/licenses/";  nil ... 
> t nil)
>        directory-files("https://www.gnu.org/licenses/";  nil ... t)
>        #f(compiled-function (d) #<bytecode 
> 0x183c21e239c1e2a3>)("https://www.gnu.org/licenses/";)
>        locate-dominating-file("https://www.gnu.org/licenses/";  #f(compiled-function 
> (d) #<bytecode 0x183c21e239c1e2a3>))

Is it possible that url-file-handler is misbehaving here?

The first lines look sensible, and then at the end we call nil as a 
function.

Of course, we probably don't want to list any files or detect the 
project when default-directory is an HTTPS URL, but how do we 
distinguish this case from others where we're just on a remote host 
(e.g. Tramp, most likely)?

And sure, Eglot triggers the problem by calling project-current 
automatically, but then project-mode-line might do the same.