Corrected a mapping case with a custom folders under msys2 root.

Using the same approach we can further refactor it focusing on drive
paths conversion first and fallback to msys2 root mapping.

Author: shikorido

lua/plenary/utils.lua

@@ -96,10 +96,16 @@ function M.posix_to_windows(posix_path)
       --vim.notify("Only '/[A-Za-z]' case: " .. posix_path, vim.log.levels.WARN)
       posix_path = posix_path:gsub("^/([A-Za-z])", "%1:\\")
       prefix_changed = true
-    else
+    elseif posix_path:find("/[A-Za-z]:?/") then
       --vim.notify("'/[A-Za-z]:?/' case: " .. posix_path, vim.log.levels.WARN)
       posix_path = posix_path:gsub("^/([A-Za-z]):?/", "%1:\\")
       prefix_changed = true
+    else
+      -- The code path can be taken only in specific cases
+      -- like a custom folder under msys2 root (/abc).
+      --vim.notify("General mapping case for given path: " .. posix_path, vim.log.levels.WARN)
+      posix_path = posix_path:gsub("^/", M.msys2_root .. "\\")
+      prefix_changed = true
     end
   end
 
@@ -123,6 +129,8 @@ function M.posix_to_windows(posix_path)
   end
 
 
+  --vim.notify("posix_to_windows will return " .. posix_path, vim.log.levels.WARN)
+
   return posix_path
 end