make lsp-treemacs-call-hierarchy show location of call instead of only the caller's name

[Jacob-Burckhardt]

For this file:

void f() {}

int main() {
   f();
   f();
}

lsp-treemacs-call-hierarchy shows something like this:

f
  main

The above does not say where in main, that f is called. It also does not show how many locations in main have calls to f. It is a minor issue for this small test program, but if it were a big project, main might have hundreds of lines which is where my suggested enhancement would be really useful.

To be specific I would prefer it to say:

f
  main line 4
  main line 5

Double-clicking on the row saying main currently moves the cursor to line 3 which is the header line of main. Naturally, I prefer it to move the cursor to inside the body at line 4 or 5 depending on which line was clicked.

clangd appears to give enough info to Emacs to allow the greater detail I request. Below I marked lines 3 and line 4 in bold. I think the LSP protocol refers to the first line in the file as line 0. That is why it says the calls to f are on lines 3 and 4. Since Emacs assigns the first line as line 1, then Emacs would simply need to add 1 to the line number that clangd gives to get lines 4 and 5 like in my example tree above.

Thanks.

V[17:33:20.129] <<< {"id":167,"jsonrpc":"2.0","method":"textDocument/prepareCallHierarchy","params":{"position":{"character":5,"line":0},"textDocument":{"uri":"file:///home/bjacob/backup/C%2B%2B/tests/a.cpp"}}}

I[17:33:20.129] <-- textDocument/prepareCallHierarchy(167)
V[17:33:20.129] ASTWorker running CallHierarchy on version 49 of /home/bjacob/backup/C++/tests/a.cpp
I[17:33:20.129] --> reply:textDocument/prepareCallHierarchy(167) 0 ms
V[17:33:20.129] >>> {"id":167,"jsonrpc":"2.0","result":[{"data":"B3A9EC6BECD5869C","kind":12,"name":"f","range":{"end":{"character":11,"line":0},"start":{"character":0,"line":0}},"selectionRange":{"end":{"character":6,"line":0},"start":{"character":5,"line":0}},"uri":"file:///home/bjacob/backup/C%2B%2B/tests/a.cpp"}]}

V[17:33:23.119] <<< {"id":168,"jsonrpc":"2.0","method":"callHierarchy/incomingCalls","params":{"item":{"data":"B3A9EC6BECD5869C","kind":12,"name":"f","range":{"end":{"character":11,"line":0},"start":{"character":0,"line":0}},"selectionRange":{"end":{"character":6,"line":0},"start":{"character":5,"line":0}},"uri":"file:///home/bjacob/backup/C%2B%2B/tests/a.cpp"}}}

I[17:33:23.119] <-- callHierarchy/incomingCalls(168)
I[17:33:23.120] --> reply:callHierarchy/incomingCalls(168) 0 ms
V[17:33:23.120] >>> {"id":168,"jsonrpc":"2.0","result":[{"from":{"data":"3017D418E3EE7259","kind":12,"name":"main","range":{"end":{"character":8,"line":2},"start":{"character":4,"line":2}},"selectionRange":{"end":{"character":8,"line":2},"start":{"character":4,"line":2}},"uri":"file:///home/bjacob/backup/C%2B%2B/tests/a.cpp"},"fromRanges":[{"end":{"character":4,"line":3},"start":{"character":3,"line":3}},{"end":{"character":4,"line":4},"start":{"character":3,"line":4}}]}]}