[Nano-devel] [PATCH] moving: allow specifying negative numbers in "Go To Line"

[Benno Schulenberg]

The negatives are taken to mean: from the end of the file,
and: from the end of the line.

This fulfills https://savannah.gnu.org/bugs/?48248.
---
 src/search.c | 23 +++++++++++++++++------
 1 file changed, 17 insertions(+), 6 deletions(-)

diff --git a/src/search.c b/src/search.c
index f724157..837767f 100644
--- a/src/search.c
+++ b/src/search.c
@@ -930,13 +930,10 @@ void do_gotolinecolumn(ssize_t line, ssize_t column, bool 
use_answer,
            return;
        }
 
-       /* Do a bounds check.  Display a warning on an out-of-bounds
-        * line or column number only if we hit Enter at the statusbar
-        * prompt. */
-       if (!parse_line_column(answer, &line, &column) ||
-                       line < 1 || column < 1) {
+       /* Extract one or two numbers from the user's response. */
+       if (!parse_line_column(answer, &line, &column)) {
            if (i == 0)
-               statusbar(_("Invalid line or column number"));
+               statusbar(_("Misformatted number"));
            display_main_list();
            return;
        }
@@ -948,10 +945,24 @@ void do_gotolinecolumn(ssize_t line, ssize_t column, bool 
use_answer,
            column = openfile->placewewant + 1;
     }
 
+    /* Take a negative line number to mean: from the end of the file. */
+    if (line < 0)
+       line = openfile->filebot->lineno + line;
+    if (line < 1)
+       line = 1;
+
+    /* Iterate to the requested line. */
     for (openfile->current = openfile->fileage; line > 1 &&
                openfile->current != openfile->filebot; line--)
        openfile->current = openfile->current->next;
 
+    /* Take a negative column number to mean: from the end of the line. */
+    if (column < 0)
+       column = strlenpt(openfile->current->data) + column + 1;
+    if (column < 1)
+       column = 1;
+
+    /* Set the x position that corresponds to the requested column. */
     openfile->current_x = actual_x(openfile->current->data, column - 1);
     openfile->placewewant = column - 1;
 
-- 
2.8.4