Subject: 28.0.60; Insufficient documentation of tab-bar.el internal functions

From: Eli Zaretskii <[email-masked]>
Date: Sun, 17 Oct 2021 11:56:01 +0300

Some functions in tab-bar.el and the data they return are documented
insufficiently, so much so that it makes the code there very hard to
develop and maintain by anyone except the original author.  Internal
functions and data strictures don't need to have doc strings, but they
do have to be explained enough for anyone to understand and modify the
code without the need to step through it with a debugger.

(Also, quite a few commands there lacked doc strings, which should be
avoided at all costs.  I fixed that today.)

I show below the places where IMO the lack of proper documentation is
particularly evident, or where the documentation is insufficient or
inaccurate.  Please fill at least those gaps; bonus points for
documenting more than this bare minimum.

  (defun tab-bar--key-to-number (key)

This function needs at least to document the meaning of each value it
can return: nil, t, or a number.

  (defun tab-bar--event-to-item (posn)
    (if (posn-window posn)
	(let ((caption (car (posn-string posn))))
	  (when caption
	    (get-text-property 0 'menu-item caption)))

This function should document the possible return values and their
meaning.  It should also say something about the text property it
retrieves from posn-string, and how that property is used.

  (defun tab-bar--format-tab (tab i)
    "Format TAB using its index I and return the result as a string."

the doc string of this function is at least inaccurate, if not
incorrect: it doesn't (always) return a string.  Please document what
it does return and the meaning of the various forms of the value.

  (defun tab-bar--format-tab-group (tab i &optional current-p)

This function lacks any documentation of the value it returns; please
add some minimal docs.

  (defun tab-bar-format-tabs-groups ()
    "Show tabs with their groups."

The doc string says "show", but this functions doesn't display
anything, AFAICT, it produces a list.  Please adjust the doc string
and add a description of the returned value.

  (defun tab-bar--tab (&optional frame)

Please add some minimal documentation of the return value.

  (defun tab-bar--current-tab (&optional tab frame)

  (defun tab-bar--current-tab-make (&optional tab)

  (defun tab-bar--current-tab-find (&optional tabs frame)

  (defun tab-bar--current-tab-index (&optional tabs frame)

  (defun tab-bar--tab-index (tab &optional tabs frame)

  (defun tab-bar--tab-index-by-name (name &optional tabs frame)

  (defun tab-bar--tab-index-recent (nth &optional tabs frame)

  (defun tab-bar--tabs-recent (&optional tabs frame)

These functions need at least some comment saying what each one of
them does.

  (defun tab-switcher-delete-from-list (tab)
    "Delete the window configuration from both lists."

Which "both lists"?

  (defun switch-to-buffer-other-tab (buffer-or-name &optional norecord)
    "Switch to buffer BUFFER-OR-NAME in another tab.
  Like \\[switch-to-buffer-other-frame] (which see), but creates a new tab.
  Interactively, prompt for the buffer to switch to."

This command should document the NORECORD argument.

Thanks.

In GNU Emacs 28.0.60 (build 72, i686-pc-mingw32)
 of 2021-10-17 built on HOME-C4E4A596F7
Repository revision: 35920791df78400a36bf4420584bd8349ce9bbee
Repository branch: emacs-28
Windowing system distributor 'Microsoft Corp.', version 5.1.2600
System Description: Microsoft Windows XP Service Pack 3 (v5.1.0.2600)

Configured using:
 'configure -C --prefix=/d/usr --with-wide-int --with-modules
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Configured features:
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Major mode: Lisp Interaction

Minor modes in effect:
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Load-path shadows:
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Memory information:
((conses 16 56715 8028)
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