And also case-sensitive searches, backward searches, and searching again.

Mentioning "GNU nano" instead of "This program" and referring to the
website instead of to a postal address.

Add the keycodes and routines to allow the user to forego setting the
mark explicitly (with M-A / ^6) and instead quickly select a few words
or lines by holding down Shift together with the movement keys.

(Some combinations with Shift are swallowed by some terminal emulators.
To work around some of those, the combinations Shift+Alt+Left/Right work
as Shift+Home/End and Shift+Alt+Up/Down work as Shift+PageUp/PageDown.)

When using the default speller or the formatter, the placewewant is
remembered.  So it should be remembered too when the user specifies
a different speller.

(This behavior was inadvertently lost last year, in commit 82d737ee.)

This fixes https://savannah.gnu.org/bugs/?48660 doubly, in case there
are other ways in which 'spell' sees words differently from 'nano'.

A keycode is either already in byte range (so there is nothing to do)
or it is not and it shouldn't be (so there is nothing to do either).

Just like when reading a file fails.  It needs the user's attention.

This fixes https://savannah.gnu.org/bugs/?48283.

Don't make it the responsibility of the executed functions to restore
the list of shortcuts of the edit window.  Just detect whether another
menu was displayed, and if so, redisplay the main menu.

This fixes https://savannah.gnu.org/bugs/?48246.

Because when undoing a paste at the end of the buffer, the tail line
probably does not exist any more.

This fixes https://savannah.gnu.org/bugs/?48222.

(It would have been the proper fix for
https://savannah.gnu.org/bugs/?44488.)

The mark has already been unset by do_cut_text().  And any assignment
to 'mark_begin' is useless when 'mark_set' is FALSE.

This fixes https://savannah.gnu.org/bugs/?48108,
and fixes https://savannah.gnu.org/bugs/?48157.

Implement its single use case by making better use of another element.

By moving the test for the only situation where do_comment() does nothing
(when only the magic line is selected) further up front, the add_undo()
can be called before the commenting/uncommenting starts and two variables
and an extra function are made unnecessary.

Reported-by: Mike Scalora <mike@scalora.org>

This fixes https://savannah.gnu.org/bugs/?48099 reported by Mike Scalora.

Store the file sizes from before and after the commenting/uncommenting
in the undo struct, so they can be restored when undoing or redoing.

This fixes https://savannah.gnu.org/bugs/?48062

.
Signed-off-by: Mike Scalora <mike@scalora.org>

This allows for commenting or uncommenting a line or a bunch of lines
with a single keystroke (default binding: M-3).  The characters used
for commenting/uncommenting are specified by the active syntax file.
Reviewed-by: Benno Schulenberg <bensberg@justemail.net>
Signed-off-by: Mike Scalora <mike@scalora.org>

If during startup there are multiple error messages, currently only the
last one remains and can be read.  To improve on that, introduce a short
pause between error messages -- even if it's not enough to read them all,
at least the user will be aware that there are multiple ones.

This also causes a few error messages to beep that currently don't beep,
such as when a file is unwritable.

This fixes https://savannah.gnu.org/bugs/?47932.

When fixing a misspelling and not answering 'All' (but 'Yes' or 'No'),
the chance is quite substantial that one will type y or n at the end of
the next word.  Diminish this chance by showing for a moment a message
on the statusbar.

Partitioning the file makes the undo system lose track, so that undoing
things has a good chance of losing data.  Instead, just make sure that
the region is marked "backwards", with current at the top and the mark
at the bottom, and then let the replace loop take care of not going
outside of the marked region.

This also has the effect that if the marked region fits entirely on the
screen, or all the misspellings are onscreen, then the screen will not
be scrolled at all.  Which makes for a smooth experience.

This fixes https://savannah.gnu.org/bugs/?47836,
and fixes https://savannah.gnu.org/bugs/?45573.

Since nano-2.4.1, reading in or pasting a large piece of text would put
the cursor on the bottom line, leaving only one line of the non-read or
non-pasted text visible.  This is different from the centering behavior
of Pico, and somewhat disorienting, as you can't see "where you are" any
more in relation to the file as it was.

So now center the cursor whenever the read or pasted text is larger than
the screen, but don't center it when the text fits entirely on the screen.
(The latter avoids the effect of the screen jumping unnecessarily when
inserting just a few lines while the cursor is near the bottom.)

To achieve this behavior: default to focusing, and temporarily set it to
FALSE when the focusing effect is unwanted.

This fixes https://savannah.gnu.org/bugs/?47841.

When starting to replace misspelled words, pass the actual position
of the cursor instead of the position of the first found occurrence,
so that the cursor position will be updated for changed lengths.

This fixes https://savannah.gnu.org/bugs/?47834.

When we're spell checking, we don't need a special mechanism to detect
we have come full circle: reaching the end-of-buffer means we're done.
So don't bother to reset came_full_circle when we're spell checking
(when begin == NULL) but simply ignore its value.

For a little contrast with the function edit_refresh() -- it's
annoying that when you search for the latter you get to see all
the settings of the flag too.

Instead of saving the current value of placewewant, then setting the
new value, and then passing the old value to edit_redraw() in seven
different places, just let edit_redraw() do this saving and setting.

In the bargain placewewant is now only recalculated when it matters
-- when allow_update is TRUE -- and not when it's superfluous.