Add code for "preserving" window sizes.

* frame.c (frame_windows_min_size): New argument IGNORE.
(adjust_frame_size): When called from change_frame_size call
frame_windows_min_size with IGNORE Qt so we can ignore size
restrictions.

* dired.el (dired-pop-to-buffer): Call fit-window-to-buffer with
`preserve-size' t.
(dired-mark-pop-up): Preserve size of window showing marked
files.
* electric.el (Electric-pop-up-window):
* help.el (resize-temp-buffer-window): Call fit-window-to-buffer
with `preserve-size' t.
* minibuffer.el (minibuffer-completion-help): Use
`resize-temp-buffer-window' instead of `fit-window-to-buffer'
(Bug#19355).  Preserve size of completions window.
* register.el (register-preview): Preserve size of register
preview window.
* tmm.el (tmm-add-prompt): Call fit-window-to-buffer
with `preserve-size' t (Bug#1291).
* window.el (with-displayed-buffer-window): Add calls to
`window-preserve-size'.
(window-min-pixel-size, window--preservable-size)
(window-preserve-size, window-preserved-size)
(window--preserve-size, window--min-size-ignore-p): New
functions.
(window-min-size, window-min-delta, window--resizable)
(window--resize-this-window, split-window-below)
(split-window-right): Amend doc-string.
(adjust-window-trailing-edge): Handle preserving window
sizes.  Signal user-error instead of an error when there's no
window above or below.
(window--min-size-1, window-sizable, window--size-fixed-1)
(window-size-fixed-p, window--min-delta-1)
(frame-windows-min-size, window--max-delta-1, window-resize)
(window--resize-child-windows, window--resize-siblings)
(enlarge-window, shrink-window, split-window): Handle preserving
window sizes.
(window--state-put-2): Handle horizontal scroll bars.
(window--display-buffer): Call `preserve-size' if asked for.
(display-buffer): Mention `preserve-size' alist member in
doc-string.
(fit-window-to-buffer): New argument PRESERVE-SIZE.

3 files changed, 14 insertions, 9 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 2b125d52723..6fabfb49ea4 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,10 @@
+2014-12-18  Martin Rudalics  <rudalics@gmx.at>
+
+        * frame.c (frame_windows_min_size): New argument IGNORE.
+        (adjust_frame_size): When called from change_frame_size call
+        frame_windows_min_size with IGNORE Qt so we can ignore size
+        restrictions.
+
 2014-12-18  Eli Zaretskii  <eliz@gnu.org>
 
         * font.c (Ffont_info): Add more font information to the vector
diff --git a/src/frame.c b/src/frame.c
index eaab63a0ea4..31273665e88 100644
--- a/src/frame.c
+++ b/src/frame.c
@@ -335,9 +335,9 @@ predicates which report frame's specific UI-related capabilities.  */)
 }
 
 static int
-frame_windows_min_size (Lisp_Object frame, Lisp_Object horizontal, Lisp_Object pixelwise)
+frame_windows_min_size (Lisp_Object frame, Lisp_Object horizontal, Lisp_Object ignore, Lisp_Object pixelwise)
 {
-  return XINT (call3 (Qframe_windows_min_size, frame, horizontal, pixelwise));
+  return XINT (call4 (Qframe_windows_min_size, frame, horizontal, ignore, pixelwise));
 }
 
 
@@ -419,8 +419,10 @@ adjust_frame_size (struct frame *f, int new_width, int new_height, int inhibit,
   /* The following two values are calculated from the old window body
      sizes and any "new" settings for scroll bars, dividers, fringes and
      margins (though the latter should have been processed already).  */
-  min_windows_width = frame_windows_min_size (frame, Qt, Qt);
-  min_windows_height = frame_windows_min_size (frame, Qnil, Qt);
+  min_windows_width
+    = frame_windows_min_size (frame, Qt, (inhibit == 5) ? Qt : Qnil, Qt);
+  min_windows_height
+    = frame_windows_min_size (frame, Qnil, (inhibit == 5) ? Qt : Qnil, Qt);
 
   if (inhibit >= 2 && inhibit <= 4)
     /* If INHIBIT is in [2..4] inhibit if the "old" window sizes stay
diff --git a/src/window.c b/src/window.c
index ca2bc74fcf4..2177a1d3966 100644
--- a/src/window.c
+++ b/src/window.c
@@ -4135,11 +4135,7 @@ values.  */)
 
 /* Resize frame F's windows when number of lines of F is set to SIZE.
    HORFLAG 1 means resize windows when number of columns of F is set to
-   SIZE.  PIXELWISE 1 means to interpret SIZE as pixels.
-
-   This function can delete all windows but the selected one in order to
-   satisfy the request.  The result will be meaningful if and only if
-   F's windows have meaningful sizes when you call this.  */
+   SIZE.  PIXELWISE 1 means to interpret SIZE as pixels.  */
 void
 resize_frame_windows (struct frame *f, int size, bool horflag, bool pixelwise)
 {