Most people who make use of 'do_findprevious' and 'do_findnext'
will not make use of 'do_search' (the default binding of M-W),
so for them it is superfluous to remember the state of the
Backwards toggle in the Search menu.  For the people that do
mix the usage of Alt+Up/Down with M-W, it means that M-W will
always search in the same direction as the last search.  It is
a small change in behavior.

The basic idea is that the cursor is always off, except when it needs
to be on: when waiting for text input, and in a few other cases: when
something was searched and found in the help viewer, and in the file
browser when option -g is in effect.

This fixes https://savannah.gnu.org/bugs/?51923

.
Reported-by: Mike Frysinger <vapier@gentoo.org>

When reducing the search string to at most half the screen width,
it should employ its width in columns, not its length in bytes.

Also adjust the type of a variable.

This fixes http://savannah.gnu.org/bugs/?52057.

Signed-off-by: Marco Diego Aurélio Mesquita <marcodiegomesquita@gmail.com>

Without them, nano still compiles for me, with everything enabled,
even when using --enable-debug, --enable-utf8, and --with-slang.

When not using --smooth (nor 'set smooth'), and a line near or beyond
the end-of-file is addressed with the + command-line argument, then
center the cursor, just like Pico does -- so in the default mode,
nano is again more like Pico.

This partially addresses https://savannah.gnu.org/bugs/?51489.

spotlight() now displays softwrapped lines chunk by chunk instead of all
at once.  Since softwrapped lines are no longer of constant width, the
latter approach would fail if softwrapping breaks the spotlighted text.

Instead of taking a string, spotlight() now takes the starting and ending
columns of that string.  Also, its handling of softwrapped lines is now
split off into a separate function, spotlight_softwrapped().

get_chunk_row() replaces the formula "column / editwincols".

get_chunk_leftedge() replaces "(column / editwincols) * editwincols".

get_last_chunk_row() replaces "strlenpt() / editwincols".

get_last_chunk_leftedge() replaces "(strlenpt() / editwincols) * editwincols".

This prepares us for any changes in those formulas, and for more such
functions later.

They can be given at the prompt, so it's better to accept them on the
command line too.

Achieve this by making the suppression flag global, so that we can
just reset it instead of making an improper call of do_cursorpos().

This fixes the secondary part of https://savannah.gnu.org/bugs/?51134.

When the column given in gotoline() is beyond the last available
column in the row of the last chunk, then set placewewant to the
actual end of the chunk, to prevent surprising jumps to the left
when moving up or down from there.

This fixes https://savannah.gnu.org/bugs/?50995.

Also remove a superfluous check for 'do_replace' -- it never gets
bound in the Search/Replace menus.

And hide the cursor again as soon as the user scrolls.
Achieve this through making the 'didfind' variable global.

Also, remove a superfluous call of wnoutrefresh(), as bottombars()
already does that.

This fixes https://savannah.gnu.org/bugs/?50918

.
Reported-by: David Lawrence Ramsey <pooka109@gmail.com>

Allow the user to search in a help text with ^W and M-W.

Achieve this by not writing the help text directly to the screen
but first writing it to a temporary file and then opening this file
in a new buffer, and treating it specially: the normal file-reading
feedback is suppressed, the titlebar shows the headline of the text,
the cursor is hidden, and the menu is limited to just the up and down
movements and searching.

This fulfills https://savannah.gnu.org/bugs/?28994

.
Signed-off-by: Rishabh Dave <rishabhddave@gmail.com>

The interval 2013-2017 for the Free Software Foundation is valid
because in those years there were releases with changes by either
Chris or David, and the GNU maintainers guide advises to mention
a new year in all files of a package, not just in the ones that
actually changed, and be done with it for the rest of the year.

Also, don't bother copying the found bracket -- just compare it in situ
and thus elide a variable.

Verify at startup that the number is not too small.

In do_replace(), replacing text may change firstcolumn if the next match
is offscreen, and replacing text after that will not change it back.  In
order to keep the viewport unchanged, we have to save and restore not
just edittop, but firstcolumn as well.

Use go_forward_chunks() to count softwrapped chunks between the current
cursor position and the bottom of the file.  Now softwrap mode and
non-softwrap mode behave the same way when moving to a line and column
non-interactively, instead of the former's always centering the screen.

Most of these variables are freed moments later -- reallocating
them is thus a waste of time.

Now that we pull in the gnulib regex module, we can assume it exists.

Reflect the significant changes in painting and regex searching
in the copyright notices.

When replacements are made, nothing needs to be reset any more
(it was done insufficiently anyway).  Just make sure the screen
is refreshed when all is done -- this may be superfluous when
doing interactive replacements, but not when replacing all.

Just like when spell-checking, there is no need to wrap around when
doing replacements in a region, because a region cannot straddle the
buffer's edges.

This is the proper fix for https://savannah.gnu.org/bugs/?50158,
and fixes https://savannah.gnu.org/bugs/?50273.

After the changes to the search routine, it is no longer necessary to
take one step back before starting a replacement session.

This fixes https://savannah.gnu.org/bugs/?50147.

Even when a match falls within the marked region, this does not mean
that it is a true match when already the whole file has been searched,
because then this is the second time we find this match.

This fixes https://savannah.gnu.org/bugs/?50158.

The spell fixer does not provide a beginning line, so the search routine
should then not try to refer to any data of this line.  Also, since the
changes to the search routine there is no need any more to retreat one
step before starting to search for a misspelled word.

This fixes https://savannah.gnu.org/bugs/?50159.

When the user answered No to a replacement prompt, skip the match
at the current position, so we don't stay stuck there.

Also, when replacing in the backward direction, or the match is
of length zero, skip the match at the current position, to not
get stuck.

This fixes https://savannah.gnu.org/bugs/?50126

.
Reported-by: David Lawrence Ramsey <pooka109@gmail.com>

This also fixes https://savannah.gnu.org/bugs/?50137,
and refixes https://savannah.gnu.org/bugs/?48635,
and fixes https://savannah.gnu.org/bugs/?50144.

That is: remove the special treatment of BOW anchors, and instead make
regexes match against the whole line instead of against an artificially
shortened one, because the latter method creates ghost matches: matches
at the starting point of the search that aren't really matches when seen
in the context of the whole line.

This fixes https://savannah.gnu.org/bugs/?50030.

When the tail of a match falls outside of the marked region,
it is in fact not a match and should not be replaced.

This fixes https://savannah.gnu.org/bugs/?50136.

When a replacement happens right at where the cursor sits, the position
of the cursor should not be adjusted, because the real cursor position
is between the current character and the preceding one: the place where
the cursor is shown is in fact right /after/ the insertion point.

This fixes https://savannah.gnu.org/bugs/?50134,
and fixes https://savannah.gnu.org/bugs/?50135.