bug#19012: 25.0.50; `help-window-select'

[martin rudalics]

> 1. The `temp-buffer-*-hook's are not only about showing *Help*.
>     That workaround thus affects more than it should.

`temp-buffer-window-setup-hook' is run with *Help* current.  So you
won't have any problems discriminating this special case.

> 2. Users of `w32*' should not need to do that explicitly
>     themselves.  Perhaps Emacs can do the equivalent, itself (but
>     limited to *Help*, not affecting all temp buffer display).

I cannot possibly use a feature like `w32-grab-focus-on-raise' whose
semantics I neither understand nor can reenact in my environment in the
frame/window code of Emacs.

But we could change `help-window-setup' as follows:

(defun help-window-setup (window &optional value)
  "Set up help window WINDOW for `with-help-window'.
WINDOW is the window used for displaying the help buffer.
Return VALUE."
  (let* ((help-buffer (when (window-live-p window)
                        (window-buffer window)))
         (help-setup (when (window-live-p window)
                       (car (window-parameter window 'quit-restore)))))
    (when help-buffer
      ;; Handle `help-window-point-marker'.
      (when (eq (marker-buffer help-window-point-marker) help-buffer)
        (set-window-point window help-window-point-marker)
        ;; Reset `help-window-point-marker'.
        (set-marker help-window-point-marker nil))

      (cond
       ((or (eq window (selected-window))
            (and (or (eq help-window-select t)
                     (eq help-setup 'frame)
                     (and (eq help-window-select 'other)
                          (eq (window-frame window) (selected-frame))
                          (> (length (window-list nil 'no-mini)) 2)))
                 (select-window window)))
        (when help-window-select
          (select-frame-set-input-focus (window-frame window)))
        ;; The help window is or gets selected ...
        (help-window-display-message
         (cond
          ((eq help-setup 'window)
           ;; ... and is new, ...
           "Type \"q\" to delete help window")
          ((eq help-setup 'frame)
           "Type \"q\" to quit the help frame")
          ((eq help-setup 'other)
           ;; ... or displayed some other buffer before.
           "Type \"q\" to restore previous buffer"))
         window t))
       ((and (eq (window-frame window) (selected-frame))
             (= (length (window-list nil 'no-mini)) 2))
        ;; There are two windows on the help window's frame and the
        ;; other one is the selected one.
        (help-window-display-message
         (cond
          ((eq help-setup 'window)
           "Type \\[delete-other-windows] to delete the help window")
          ((eq help-setup 'other)
           "Type \"q\" in help window to restore its previous buffer"))
         window 'other))
       (t
        ;; The help window is not selected ...
        (help-window-display-message
         (cond
          ((eq help-setup 'window)
           ;; ... and is new, ...
           "Type \"q\" in help window to delete it")
          ((eq help-setup 'other)
           ;; ... or displayed some other buffer before.
           "Type \"q\" in help window to restore previous buffer"))
         window))))
    ;; Return VALUE.
    value))

martin