How to make comment-dwim comment from cursor position if its middle of the line?

Question

I am using comment-dwim-line to comment out multiple lines. For this, I automatically move cursor always to the beginning of a line. I just want to use this behavior if the cursor is at beginning of a line or multiple line is selected.

If the cursor is in the middle of a line, I just want to add a comment character where the cursor is located.

The code I am using:

(defun comment-dwim-line (&optional arg)
  "Replacement for the comment-dwim command.
        If no region is selected and current line is not blank and we are not at the end of the line,
        then comment current line.
        Replaces default behaviour of comment-dwim, when it inserts comment at the end of the line."
  ;; http://www.opensubscriber.com/message/[email protected]/10971693.html
  (interactive "*P")
  (comment-normalize-vars)
  (if (and (not (region-active-p)) (not (looking-at "[ \t]*$")))
      (comment-or-uncomment-region (line-beginning-position) (line-end-position))
    (comment-dwim arg)))

(global-set-key (kbd "C-c C-;") 'comment-dwim-line)

Here it is possible to apply normal comment out behavior if the cursor is not at the beginning of a line:

def main():
    x = 10   
  (^)
   |__ cursor is here when `comment-dwim-line` is applied it becomes

This is ok.

def main():
    # x = 10

---

But for the following example:

def main():
    x = 10   my commment
          (^)
           |__ cursor is here when `comment-dwim-line` is applied

    # x = 10   my commment

It becomes:

def main():
    # x = 10  my commment

wanted behavior would be: x = 10 # my commment as:

def main():
    x = 10 # my commment

Answer 1

Experimentally, changing (line-beginning-position) to (point) in the arg list of comment-or-uncomment-region gives the behaviour you describe:

(defun comment-dwim-line (&optional arg)
  (interactive "*P")
  (comment-normalize-vars)
  (if (and (not (region-active-p)) (not (looking-at "[ \t]*$")))
      (comment-or-uncomment-region (point) (line-end-position))
    (let ((comment-column (current-column)))
      (comment-dwim arg))))