Incorrect Variable Name in DAP Request

[Eugenij-W]

Description

I encountered a bug in Vimspector while hovering over a specific variable in C++ code. When the cursor is positioned over the word "second" in the following snippet:

for (int i=0; i<6; ++i) {
    auto& it = proc.modules.insert(std::make_pair(1620+i,
        IMDBG::MODULE())).first->second;
}

the Debug Adapter Protocol (DAP) request to retrieve the value of the variable does not use the expected name ".first->second" Instead, it is sent with the name "."

Moreover, Vimspector does not properly capture variables with scope. For instance, when hovering over a namespaced variable like ns::var, the request sent will simply use "var" instead of "ns::var."

Additionally, Vimspector frequently sends DAP requests with clearly incorrect variable names, such as ")".

A simple check to ensure that variable names do not start with a dot, along with proper handling of variable contexts, could help reduce unnecessary DAP requests and result in cleaner logs.

Is it reproducible in vim?

Reproducible in Vim

Works with clean config?

Yes

Sample project works?

No sample project for this filetype

Minimal Reproduction

List of steps to reproduce:

for (int i=0; i<6; ++i) {
    auto& it = proc.modules.insert(std::make_pair(1620+i,
        IMDBG::MODULE())).first->second;
}

1. Open the C++ file containing the above code snippet in Vimspector.
2. Hover the cursor over the word "second."
3. Monitor the DAP request generated.

Expected Behaviour

Given that the context for the expression in the parentheses is likely not available, Vimspector should ideally either:

1. Construct the request name as ".first->second" to accurately reflect the variable's context.
2. Cancel the request altogether when context is unavailable.

Actual Behaviour

The DAP request is sent with the name ".", leading to an incorrect retrieval attempt.

Additional information

No response

Installation Type

Other (specify in notes)

Vimspector version

0da16c6

Debug Info

Log file

Vim version

VIM - Vi IMproved 9.0 (2022 Jun 28, compiled Mar 25 2024 21:43:35)
MS-Windows 32-bit GUI version with OLE support
Included patches: 1-495
Compiled by User@QXP
Huge version with GUI.  Features included (+) or not (-):
+acl                +cursorbind         +iconv/dyn          -mzscheme           -sodium             +vartabs
+arabic             +cursorshape        +insert_expand      -netbeans_intg      +sound              +vertsplit
+autocmd            +dialog_con_gui     +ipv6               +num64              +spell              +vim9script
+autochdir          +diff               +job                +ole                +startuptime        +viminfo
+autoservername     +digraphs           +jumplist           +packages           +statusline         +virtualedit
+balloon_eval       -directx            +keymap             +path_extra         -sun_workshop       +visual
-balloon_eval_term  -dnd                +lambda             -perl               +syntax             +visualextra
+browse             -ebcdic             +langmap            +persistent_undo    +tag_binary         +vreplace
++builtin_terms     +emacs_tags         +libcall            +popupwin           -tag_old_static     -vtp
+byte_offset        +eval               +linebreak          -postscript         -tag_any_white      +wildignore
+channel            +ex_extra           +lispindent         +printer            -tcl                +wildmenu
+cindent            +extra_search       +listcmds           +profile            -termguicolors      +windows
+clientserver       -farsi              +localmap           -python             +terminal           +writebackup
+clipboard          +file_in_path       +lua/dyn            +python3/dyn        -termresponse       -xfontset
+cmdline_compl      +find_in_path       +menu               +quickfix           +textobjects        -xim
+cmdline_hist       +float              +mksession          +reltime            +textprop           -xpm_w32
+cmdline_info       +folding            +modify_fname       +rightleft          -tgetent            -xterm_save
+comments           -footer             +mouse              -ruby               +timers             
+conceal            +fullscreen         +mouseshape         +scrollbind         +title              
+cryptv             +gettext/dyn        +multi_byte_ime/dyn +signs              +toolbar            
+cscope             -hangul_input       +multi_lang         +smartindent        +user_commands      
   system vimrc file: "$VIM\vimrc"
     user vimrc file: "$HOME\_vimrc"
 2nd user vimrc file: "$HOME\vimfiles\vimrc"
 3rd user vimrc file: "$VIM\_vimrc"
      user exrc file: "$HOME\_exrc"
  2nd user exrc file: "$VIM\_exrc"
  system gvimrc file: "$VIM\gvimrc"
    user gvimrc file: "$HOME\_gvimrc"
2nd user gvimrc file: "$HOME\vimfiles\gvimrc"
3rd user gvimrc file: "$VIM\_gvimrc"
       defaults file: "$VIMRUNTIME\defaults.vim"
    system menu file: "$VIMRUNTIME\menu.vim"
Compilation: gcc -I. -Iproto -static -DWIN32 -DWINVER=0x501 -D_WIN32_WINNT=0x501 -D_WIN32_IE=0x0600 -DHAVE_PATHDEF -DFEAT_HUGE -DHAVE_STDINT_H -DHAVE_GETTEXT -DHAVE_LOCALE_H -DDYNAMIC_GETTEXT -DFEAT_OLE -DFEAT_CSCOPE -DFEAT_JOB_CHANNEL -DFEAT_IPV6 -DFEAT_TERMINAL -DFEAT_SOUND -DFEAT_GUI_MSWIN -DFEAT_CLIPBOARD -DFEAT_MBYTE_IME -DDYNAMIC_IME -DDYNAMIC_ICONV -pipe -march=pentium -Wall -Ik:/PROJECTS/OPEN/!3RD/lua-5.3.0/dist/include -Ik:/PROJECTS/OPEN/!3RD/lua-5.3.0/dist -DFEAT_LUA -DDYNAMIC_LUA -DDYNAMIC_LUA_DLL="lua53.dll" -DFEAT_PYTHON3 -DDYNAMIC_PYTHON3 -DDYNAMIC_PYTHON3_DLL="python36.dll" -O3 -fomit-frame-pointer -freg-struct-return
Linking: gcc -I. -Iproto -static -DWIN32 -DWINVER=0x501 -D_WIN32_WINNT=0x501 -D_WIN32_IE=0x0600 -DHAVE_PATHDEF -DFEAT_HUGE -DHAVE_STDINT_H -DHAVE_GETTEXT -DHAVE_LOCALE_H -DDYNAMIC_GETTEXT -DFEAT_OLE -DFEAT_CSCOPE -DFEAT_JOB_CHANNEL -DFEAT_IPV6 -DFEAT_TERMINAL -DFEAT_SOUND -DFEAT_GUI_MSWIN -DFEAT_CLIPBOARD -DFEAT_MBYTE_IME -DDYNAMIC_IME -DDYNAMIC_ICONV -pipe -march=pentium -Wall -Ik:/PROJECTS/OPEN/!3RD/lua-5.3.0/dist/include -Ik:/PROJECTS/OPEN/!3RD/lua-5.3.0/dist -DFEAT_LUA -DDYNAMIC_LUA -DDYNAMIC_LUA_DLL="lua53.dll" -DFEAT_PYTHON3 -DDYNAMIC_PYTHON3 -DDYNAMIC_PYTHON3_DLL="python36.dll" -O3 -fomit-frame-pointer -freg-struct-return -s -mwindows -o gvim.exe -lkernel32 -luser32 -lgdi32 -ladvapi32 -lcomdlg32 -lcomctl32 -lnetapi32 -lversion -lwsock32 -lws2_32 -loleaut32 -lwinmm -lole32 -luuid

Python version

No response

Neovim diagnostics

Operating System

No response

Declaration

• I have read and understood CONTRIBUTING.md
• I have read and understood the CODE_OF_CONDUCT.md

[puremourning]

in this situation, what expression would you expect vimspector to pick?

vimspector is very dumb about language syntax so It just gets a very simple word under the cursor.

if your expression is more complicated you should use a visual selection, like this:

But tbh in this case, I'm not sure the debugger is even going to be able to give you an evaluation for second

[Eugenij-W]

You are right, but it would probably be better not to send the request at all if the variable name is not fully constructed, otherwise you can get the value of another variable with the same name as a class member, I think you need to capture the name taking into account ->/::/. And if it looks incomplete (the first token is not a name), then do not send the request.

[puremourning]

I think vimspector uses iskeyword from vim. I can check but there's little chance that I can support the syntax and semantics from every language.

If this is so broken I'll just remove the feature entirely.