Matching the command executor with the shell option

[georgejean]

First of all, thank you for this great plugin!
I point out that I'm a Windows user.
I've never managed to get the following instruction to work in the chat buffer, regardless of my shell configuration ('cmd.exe' or 'pwsh.exe').

Using @full_stack_dev, create a folder with three subfolders, each containing two or three code files.

I then decided to use the bash shell with these options:

if vim.fn.executable 'sh.exe' == 1 then
  vim.o.shell = 'sh.exe'
  vim.o.shellcmdflag = '-c'
  vim.o.shellxquote = ''
  vim.o.shellquote = ''
  vim.o.shellslash = true
end

and (I think this point is crucial), I also modified the file
cmd.lua as follows:

--- a/lua/codecompanion/strategies/chat/agents/executor/cmd.lua
+++ b/lua/codecompanion/strategies/chat/agents/executor/cmd.lua
@@ -48,8 +48,11 @@ function CmdExecutor:run(cmd, index)
   log:debug("CmdExecutor:run %s", cmd)
 
   local job = Job:new({
-    command = (vim.fn.has("win32") == 1 and "cmd.exe" or "sh"),
-    args = { vim.fn.has("win32") == 1 and "/c" or "-c", table.concat(cmd.cmd or cmd, " ") },
+    command = (vim.fn.has("win32") == 1 and vim.fn.executable("sh.exe") == 0 and "cmd.exe" or "sh"),
+    args = {
+      vim.fn.has("win32") == 1 and vim.fn.executable("sh.exe") == 0 and "/c" or "-c",
+      table.concat(cmd.cmd or cmd, " "),
+    },
     enable_recording = true,
     cwd = vim.fn.getcwd(),
     on_exit = function(data, code)

Therefore, I prefer to use sh on Windows for the command when it's in the PATH (which may be the case for many users since sh.exe is included with Git for Windows).

And there 🎉 🎊, the same instruction passed to the agent has worked perfectly !

I hope this can help some people, and perhaps inspire a potential pull request!

[olimorris]

Thanks so much @georgejean. Is it worthwhile turning this into a PR?

[georgejean]

Thank you for your response! I'll run some additional tests. I've used deepseek-chat as a model and I'll try with at least one other model and different shell configurations. After that, if my diagnosis is confirmed, I'll let you decide whether to make the changes directly or if you prefer a PR. Regardless, if this change is confirmed, I expect it to be beneficial for me. It would also be helpful to get feedback from other Windows users...

[olimorris]

At the very least, maybe I should make this a config option that users can swap out

[georgejean]

Hi !
Here are the results of my tests with the chat prompt:

Use @{full_stack_dev} to create a Docum folder containing two files: a Markdown tutorial in a .md file and a Lua tutorial in a .lua file.

Model	Shell config	with the 'vim.fn.executable("sh.exe")' test	Result
deepseek-chat	default (cmd)	Yes	Success
deepseek-chat	shell-bare	Yes	Success
deepseek-chat	shell	Yes	Success
deepseek-chat	default (cmd)	No	Success
deepseek-chat	shell-bare	No	~~~~~~~~
deepseek-chat	shell	No	~~~~~~~~
meta-llama/Llama-3.3-70B-Instruct-Turbo-Free	default (cmd)	Yes	Failure
meta-llama/Llama-3.3-70B-Instruct-Turbo-Free	shell-bare	Yes	Failure
meta-llama/Llama-3.3-70B-Instruct-Turbo-Free	shell	Yes	Failure
meta-llama/Llama-3.3-70B-Instruct-Turbo-Free	default (cmd)	No	Failure
meta-llama/Llama-3.3-70B-Instruct-Turbo-Free	shell-bare	No	Failure
meta-llama/Llama-3.3-70B-Instruct-Turbo-Free	shell	No	Failure

Details about the 'vim.fn.executable("sh.exe")' test:

If Yes, the "sh.exe" shell is used for the command in the executor cmd.lua. If not, it falls back to "cmd.exe".

Details about Shell config:

• default (cmd) corresponds to :

  vim.o.shell = "cmd.exe"

• shell-bare corresponds to :

  vim.o.shell = "sh.exe"

• shell corresponds to :

  vim.o.shell = 'sh.exe'
  vim.o.shellcmdflag = '-c'
  vim.o.shellxquote = ''
  vim.o.shellquote = ''
  vim.o.shellslash = true

Details about ~~~~~~~~:

deepseek-chat with shell (or shell-bare) config and "cmd.exe" for the command in the cmd.lua executor has created the correct folder Docum with the files but also an empty '-p' folder (its command being 'mkdir -p Docum'). This is therefore a very mitigated success (due to a mismatch between the two shells)...

Details about Failures:

meta-llama/Llama-3.3-70B-Instruct-Turbo-Free tries to directly create the file Docum/Lua_Tutorial.lua with the @{create_file} tools and doesn't succeed. Other tests show that Deepseek-chat also fails if it uses this tool (instead of @{cmd_runner}):

Tool create_file: **Create File Tool**: Failed to create file `Docum/Lua_Tutorial.lua` - ...a/Local/nvim-data/lazy/plenary.nvim/lua/plenary/path.lua:643: Could not create file: C:/.../Lua_Tutorial.lua

---

and here are the results for a more complex prompt:

Using @{full_stack_dev}, create a folder with three subfolders, each containing two or three code files.

Model	Shell config	with the 'vim.fn.executable("sh.exe")' test	Result
deepseek-chat	default (cmd)	Yes	Failure
deepseek-chat	shell-bare	Yes	Success
deepseek-chat	shell	Yes	Success
deepseek-chat	default (cmd)	No	Success
deepseek-chat	shell-bare	No	Failure
deepseek-chat	shell	No	Failure

We generally observe that failures are due to a mismatch between the shell option and the shell used in cmd.lua.

Conclusion

• On Windows, there is a problem when a model uses the @{create_file} tool to directly create a file (via its relative path) in a folder that does not exist (and therefore also needs to be created).
• It seems that we get better results by using a shell in cmd.lua that matches the one set in the options.
  Perhaps a patch to improve this would be to write in cmd.lua:

command = (vim.fn.has("win32") == 1 and vim.o.shell or "sh"),
args = { vim.fn.has("win32") == 1 and vim.fn.fnamemodify(vim.o.shell, ":t"):lower():match('cmd') and "/c" or "-c", table.concat(cmd.cmd or cmd, " ") },

And this would also be applicable in the case where vim.o.shell has been set to "pwsh" (powershell).