fix(context): normalize mention path handling

Normalize mention paths to relative values for mention commands, and enforce trailing separators for directory mentions using path-style-aware separators.

Author: yaadata

README.md

@@ -101,8 +101,8 @@ require("codex").setup({
 - `:CodexClose` closes the active Codex terminal session
 - `:CodexClearInput` clears the active Codex terminal input line
 - `:CodexSend` sends selected lines with path and range context.
-- `:CodexMentionFile [path]` sends `/mention` for a file (or current buffer path).
-- `:CodexMentionDirectory [path]` sends `/mention` for a directory (or current buffer's directory).
+- `:CodexMentionFile [path]` sends `/mention` for a file path, normalized to cwd-relative.
+- `:CodexMentionDirectory [path]` sends `/mention` for a directory path, normalized to cwd-relative and forced to end with a path separator.
 - `:CodexResume[!]` resumes in-process or launches `codex resume` (`!` uses
   `--last` when launching).
 - `:CodexModel` sends `/model`

docs/command-interactions.md

@@ -9,24 +9,24 @@ provider collaborators.
 
 ## Command Mapping
 
-| User Command                    | Entry Function                   | Primary Path                                          |
-| ------------------------------- | -------------------------------- | ----------------------------------------------------- |
-| `:Codex`                        | `codex.toggle()`                 | Toggle active terminal or open a focused session      |
-| `:Codex!`                       | `codex.open(true)`               | Force-open and focus terminal                         |
-| `:CodexFocus`                   | `codex.focus()`                  | Focus active session or open one                      |
-| `:CodexClose`                   | `codex.close()`                  | Close active session and reset queue                  |
-| `:CodexClearInput`              | `codex.clear_input()`            | Send `<C-c>` to active session                        |
-| `:CodexSend`                    | `codex.send_selection(opts)`     | Collect selection, format, send via queue             |
-| `:CodexMentionFile [path]`      | `codex.mention_file(path)`       | Build `/mention` payload for file and submit          |
-| `:CodexMentionDirectory [path]` | `codex.mention_directory(path)`  | Build `/mention` payload for directory and submit     |
-| `:CodexResume`                  | `codex.resume({ last = false })` | In-process `/resume` or launch `codex resume`         |
-| `:CodexResume!`                 | `codex.resume({ last = true })`  | Launch `codex resume --last` when opening new process |
-| `:CodexModel`                   | `codex.set_model()`              | Slash command wrapper (`/model`)                      |
-| `:CodexStatus`                  | `codex.show_status()`            | Slash command wrapper (`/status`)                     |
-| `:CodexPermissions`             | `codex.show_permissions()`       | Slash command wrapper (`/permissions`)                |
-| `:CodexCompact`                 | `codex.compact()`                | Slash command wrapper (`/compact`)                    |
-| `:CodexReview [instructions]`   | `codex.review(instructions)`     | Slash command wrapper (`/review ...`)                 |
-| `:CodexDiff`                    | `codex.show_diff()`              | Slash command wrapper (`/diff`)                       |
+| User Command                    | Entry Function                   | Primary Path                                                                         |
+| ------------------------------- | -------------------------------- | ------------------------------------------------------------------------------------ |
+| `:Codex`                        | `codex.toggle()`                 | Toggle active terminal or open a focused session                                     |
+| `:Codex!`                       | `codex.open(true)`               | Force-open and focus terminal                                                        |
+| `:CodexFocus`                   | `codex.focus()`                  | Focus active session or open one                                                     |
+| `:CodexClose`                   | `codex.close()`                  | Close active session and reset queue                                                 |
+| `:CodexClearInput`              | `codex.clear_input()`            | Send `<C-c>` to active session                                                       |
+| `:CodexSend`                    | `codex.send_selection(opts)`     | Collect selection, format, send via queue                                            |
+| `:CodexMentionFile [path]`      | `codex.mention_file(path)`       | Build `/mention` payload for relative file and submit                                |
+| `:CodexMentionDirectory [path]` | `codex.mention_directory(path)`  | Build `/mention` payload for relative directory (with trailing separator) and submit |
+| `:CodexResume`                  | `codex.resume({ last = false })` | In-process `/resume` or launch `codex resume`                                        |
+| `:CodexResume!`                 | `codex.resume({ last = true })`  | Launch `codex resume --last` when opening new process                                |
+| `:CodexModel`                   | `codex.set_model()`              | Slash command wrapper (`/model`)                                                     |
+| `:CodexStatus`                  | `codex.show_status()`            | Slash command wrapper (`/status`)                                                    |
+| `:CodexPermissions`             | `codex.show_permissions()`       | Slash command wrapper (`/permissions`)                                               |
+| `:CodexCompact`                 | `codex.compact()`                | Slash command wrapper (`/compact`)                                                   |
+| `:CodexReview [instructions]`   | `codex.review(instructions)`     | Slash command wrapper (`/review ...`)                                                |
+| `:CodexDiff`                    | `codex.show_diff()`              | Slash command wrapper (`/diff`)                                                      |
 
 ## Setup Registration Flow
 
@@ -164,6 +164,7 @@ init.lua mention_file(path) / mention_directory(path) -> mention module
     |- resolve path (arg or current buffer path via %:p / %:p:h)
     |- [missing path] -> log + return false, "current buffer has no file/directory path"
     |- path.to_relative(...)
+    |- [directory only] path.ensure_dir_trailing_separator(...)
     \- mention.dispatch(relative_path)
          |- formatter.format_mention(relative_path)
          |- [active + alive] provider.focus(handle) before prompt capture

lua/codex/context/mention.lua

@@ -216,6 +216,7 @@ function M.create(opts)
     end
 
     resolved_path = deps.path.to_relative(deps.vim, resolved_path)
+    resolved_path = deps.path.ensure_dir_trailing_separator(deps.vim, resolved_path)
     return dispatch_mention(resolved_path)
   end
 

lua/codex/context/path.lua

@@ -1,5 +1,58 @@
 local M = {}
 
+---Best-effort host OS check for Windows to pick default path separators.
+---@param vim_api table|nil
+---@return boolean
+local function is_windows(vim_api)
+  vim_api = vim_api or vim
+
+  local uv = vim_api.uv or vim_api.loop
+  if uv and type(uv.os_uname) == "function" then
+    local ok, uname = pcall(uv.os_uname)
+    if ok and type(uname) == "table" and type(uname.sysname) == "string" then
+      return uname.sysname:match("Windows") ~= nil
+    end
+  end
+
+  local fn = vim_api.fn
+  if type(fn) == "table" and type(fn.has) == "function" then
+    local ok_win32, has_win32 = pcall(fn.has, "win32")
+    if ok_win32 and has_win32 == 1 then
+      return true
+    end
+    local ok_win64, has_win64 = pcall(fn.has, "win64")
+    if ok_win64 and has_win64 == 1 then
+      return true
+    end
+  end
+
+  return false
+end
+
+---Choose separator by path style first, then host OS as fallback.
+---@param vim_api table|nil
+---@param path string
+---@return string
+local function choose_separator(vim_api, path)
+  if path:find("\\", 1, true) ~= nil then
+    return "\\"
+  end
+
+  if path:match("^%a:[/\\]?") or path:match("^\\\\") then
+    return "\\"
+  end
+
+  if path:find("/", 1, true) ~= nil then
+    return "/"
+  end
+
+  if is_windows(vim_api) then
+    return "\\"
+  end
+
+  return "/"
+end
+
 --- Convert an absolute file path to a cwd-relative path via fnamemodify.
 ---@param vim_api table|nil
 ---@param filepath string
@@ -18,4 +71,26 @@ function M.to_relative(vim_api, filepath)
   return filepath
 end
 
+---Ensure directory paths end with one separator matching path style/OS.
+---@param vim_api table|nil
+---@param path string
+---@return string
+function M.ensure_dir_trailing_separator(vim_api, path)
+  if path == "" then
+    return path
+  end
+
+  local separator = choose_separator(vim_api, path)
+  if path:sub(-1) == separator then
+    return path
+  end
+
+  local normalized = path:gsub("[/\\]+$", "")
+  if normalized == "" then
+    return separator
+  end
+
+  return normalized .. separator
+end
+
 return M

tests/unit/init_spec.lua

@@ -1535,14 +1535,32 @@ describe("codex.init public api", function()
     assert.equals("<termcoded:<CR>>", env.fake_vim._feedkeys_calls[1].keys)
   end)
 
+  it(
+    "mention_directory appends trailing separator when explicit directory path omits it",
+    function()
+      local env = setup_with_deps()
+
+      local ok = env.codex.mention_directory("/tmp")
+      local mention_payload_expected = "<termcoded:<C-e>><termcoded:<C-u>>/mention ../../tmp/"
+
+      assert.is_true(ok)
+      assert.equals("../../tmp/", env.formatter.mention_paths[1])
+      assert.equals(1, #env.provider.send_calls)
+      assert.equals(mention_payload_expected, env.provider.send_calls[1].text)
+    end
+  )
+
   it("mention_directory resolves current buffer directory when argument is nil", function()
     local env = setup_with_deps()
+    env.fake_vim.uv.os_uname = function()
+      return { sysname = "Linux" }
+    end
 
     local ok = env.codex.mention_directory(nil)
-    local mention_payload_expected = "<termcoded:<C-e>><termcoded:<C-u>>/mention .."
+    local mention_payload_expected = "<termcoded:<C-e>><termcoded:<C-u>>/mention ../"
 
     assert.is_true(ok)
-    assert.equals("..", env.formatter.mention_paths[1])
+    assert.equals("../", env.formatter.mention_paths[1])
     assert.equals(1, #env.provider.send_calls)
     assert.equals(mention_payload_expected, env.provider.send_calls[1].text)
   end)

tests/unit/path_spec.lua

@@ -31,4 +31,30 @@ describe("codex.context.path", function()
     local fake_vim = { fn = {} }
     assert.equals("", path.to_relative(fake_vim, ""))
   end)
+
+  describe("ensure_dir_trailing_separator", function()
+    it("adds forward slash for unix-style relative paths", function()
+      assert.equals("../", path.ensure_dir_trailing_separator(nil, ".."))
+    end)
+
+    it("keeps existing unix trailing slash", function()
+      assert.equals("../../tmp/", path.ensure_dir_trailing_separator(nil, "../../tmp/"))
+    end)
+
+    it("adds backslash for windows-style paths", function()
+      assert.equals("C:\\work\\repo\\", path.ensure_dir_trailing_separator(nil, "C:\\work\\repo"))
+    end)
+
+    it("falls back to host OS separator when style is ambiguous", function()
+      local fake_vim = {
+        uv = {
+          os_uname = function()
+            return { sysname = "Windows_NT" }
+          end,
+        },
+      }
+
+      assert.equals(".\\", path.ensure_dir_trailing_separator(fake_vim, "."))
+    end)
+  end)
 end)