Jump to nearest diff fails (following the demo)

[deas]

Hi!

First of all I'd like to say that the demo at the very top of the README.md impressed me a lot!

However, I am having a hard time following it, and end up failing at gj (Jump to nearest diff) after hitting Enter on a quickfix list entry. I am using lazyvim and I see this with neovim 0.10.4 and 0.11.0.

It also appears things have changed a bit since this video was recorded.

My intial prompt is

> #files

Optimize this project.

It all pretty much goes as expected until I hit gj which appears to do nothing. It does not open a buffer with the file affected by the diff.

Below is what it looks like.

[deathbeam]

It looks like you have incorrect file header generated there, what model are you using? some of them are very bad at following actual instructions :d but gpt4-o and claude should work fine

[deathbeam]

also are you overriding system prompt with anything?

[deas]

No, not overriding system prompt. Actually no customization at all.

Seeing the same behavior with Claude 3.7 Sonnet and GPT-4o.

[deathbeam]

Hmm i cant reproduce this at all, does this happen consistently to you or just in this 1 case?

[Krakazybik]

I'm having the same issue with applying changes — it constantly adds either #file or -context to the file path. It feels like the following syntax block is somehow affecting it:

>#<command>:`<input>`

Examples:
> #file:`path/to/file.js`        (loads specific file)  
> #buffers:`visible`             (loads all visible buffers)  
> #git:`staged`                  (loads git staged changes)  
> #system:`uname -a`             (loads system information)  

Guidelines:
- Always request context when needed rather than guessing about files or code
- Use the > format on a new line when requesting context
- Output context commands directly - never ask if the user wants to provide information
- Assume the user will provide requested context in their next response

Available context providers and their usage:

 - #buffer: Includes specified buffer in chat context. Supports input (default current).

 - #buffers: Includes all buffers in chat context. Supports input (default listed).

 - #file: Includes content of provided file in chat context. Supports input.

 - #filenames: Includes names of all non-hidden files in the current workspace in chat context. Supports input (glob pattern).

 - #files: Includes all non-hidden files in the current workspace in chat context. Supports input (glob pattern).

 - #git: Requires `git`. Includes current git diff in chat context. Supports input (default unstaged, also accepts commit number).

 - #quickfix: Includes quickfix list file contents in chat context.

 - #register: Includes contents of register in chat context. Supports input (default +, e.g clipboard).

 - #system: Includes output of provided system shell command in chat context. Supports input.
   
   Important:
   - Only use system commands as last resort, they are run every time the context is requested.
   - For example instead of curl use the url context, instead of finding and grepping try to check if there is any context that can query the data you need instead.
   - If you absolutely need to run a system command, try to use read-only commands and avoid commands that modify the system state.
   

 - #url: Includes content of provided URL in chat context. Supports input.

[deas]

@deathbeam I see the issue when trying to reproduce what you did in the video. I do not see it using the content of a single file buffer as context. In that case gj works as expected.

Coming back to the issue (learning lua/neovim along the way) , it appears to be getting diff wrong. I added a few lines to look a bit closer:

  jump_to_diff = {
    normal = 'gj',
    callback = function(source)
      local diff = get_diff(copilot.chat:get_closest_block())
      log.debug('Diff : ', vim.inspect(diff))
      diff = prepare_diff_buffer(diff, source)
      if not diff then
        return
      end

      copilot.set_selection(diff.bufnr, diff.start_line, diff.end_line)
    end,
  },

Hitting CR at item 4 of the quickfix list took me to the expected diff in the response as expected.

Hitting gj with the cursor on that diff is when things go wrong for me. The screenshot below is what I see after hitting gj in such a case.

In the logs, I see:

[DEBUG Sa 05 Apr 2025 11:28:18 CEST] /home/deas/.local/share/nvim/lazy/CopilotChat.nvim/lua/CopilotChat/config/mappings.lua:252: Diff :  {
  change = "--- Get diagnostics in a given range\n--- @param bufnr number\n--- @param start_line number?\n--- @param end_line number?\n--- @param max_diagnostics number? Maximum number of diagnostics to return\n--- @return table<CopilotChat.Diagnostic>|nil\nfunction M.diagnostics(bufnr, start_line, end_line, max_diagnostics)\n  local diagnostics = vim.diagnostic.get(bufnr)\n  local range_diagnostics = {}\n  local severity = {\n    [1] = 'ERROR',\n    [2] = 'WARNING',\n    [3] = 'INFORMATION',\n    [4] = 'HINT',\n  }\n\n  max_diagnostics = max_diagnostics or 100 -- Reasonable default limit\n  local count = 0\n\n  for _, diagnostic in ipairs(diagnostics) do\n    if count >= max_diagnostics then\n      break\n    end\n    \n    local lnum = diagnostic.lnum + 1\n    if (not start_line or lnum >= start_line) and (not end_line or lnum <= end_line) then\n      table.insert(range_diagnostics, {\n        severity = severity[diagnostic.severity],\n        content = diagnostic.message,\n        start_line = lnum,\n        end_line = diagnostic.end_lnum and diagnostic.end_lnum + 1 or lnum,\n      })\n      count = count + 1\n    end\n  end\n\n  return #range_diagnostics > 0 and range_diagnostics or nil\nend",
  end_line = 802,
  filename = "utils.lua",
  filetype = "lua",
  reference = "  ~/.local/share/nvim/lazy/CopilotChat.\n   doc\n   lua                               \n   plugin\n   test\n   󰉻 CHANGELOG.md\n   󰺾 CONTRIBUTING.md\n    LICENSE\n   󰍔 MIGRATION.md\n   󱁤 Makefile\n    README.md\n   󰦪 cspell-tool.txt\n   󰘦 cspell.json\n   󰌝 index.html\n   󰘦 renovate.json\n   * structure.drawio\n   󰘦 syntax.json\n   󰦪 version.txt\n   (10 hidden items)",
  start_line = 767
}

This looks wrong to me. Don't know if a path is needed to get it right, but the file should have been client.lua. The reference value may not be a problem here, but it still confuses me a bit.

[bechampion]

Im working with this

function FixCopilotChat()
  -- Replace the pattern (#file:<filename>-context?) with (<filename>)
  -- If the pattern is not found, do nothing
  local success = pcall(vim.cmd, [[%s/(#file:\(\w\+.\w\+\)-context\?)/(\1)]])
  if not success then
    print("Pattern not found")
  end
  vim.cmd("normal! G")
end

vim.api.nvim_set_keymap("n", "<C-t>", "<cmd>lua FixCopilotChat()<CR>", {})
vim.api.nvim_set_keymap("i", "<C-t>", "<cmd>lua FixCopilotChat()<CR>", {})

So i press C-t C-y and it fixes the context , is there any way to call CopilotChat accept diff externally , so i don't have to use two mappings ?

[deathbeam]

Not atm, but you can also just call that cmd as default callback (see config.callback) and have it automated. Then you will have only 1 mapping

[bechampion]

Amazing that works perfect! thank you @deathbeam

[deas]

Iceberg ahead? Good to know! :)

Was observing some more issues while trying to follow the demo running the main branch. Took a moment and tried the tools branch now as it appears to be somewhat close to merge in. Seeing some basic issues with it. Ran into Model not found: gpt-4o-2024-11-20 straight away. No problem, just saying.

Being on my newbie discovery journey, I found there is avante.nvim which appears to mimic Cursor and supports mcphub.nvim as well. Would be interesting to know how CopilotChat.nvim compares roughly (e.g. goals).

[deathbeam]

The model issue should be fixed (on both main branch and tools branch). Any other issues you found on tools branch?

For avante, as you said its trying to replicate Cursor as its goal.
For this plugin, the goal is to focus on implementation that makes sense in neovim instead because I dont think the cursor model and chat interface does.
That is why the primary way of for example storing state is to have it directly in chat as text and outside of default configuration to always have every setting clearly visible in chat as well, with nothing hidden from the user, and everything removable/changeable. That is why instead of storing stuff in some hidden state that is changeable with commands, this plugin uses "sticky prompts" that is simply text that is just copy pasted to next prompt and supports changing most of the actual behaviour by simply writing it in prompt (and "saving" is just copying that to next prompt).
Also I try to focus on having the plugin be very scriptable, for example I dont think any other LLM plugin for neovim currently has as good headless mode as this plugin (where you can interact with the chat through lua only and without any chat interface, useful for some automation like automatically generating commit messages when you open COMMIT_MSG etc).
Also I dont try to support every possible provider by default, instead this plugin only supports Copilot by default, but adding most of providers that have openai compatible apis is super simple, but community maintained.