vim-patch:9.1.0537: signed number detection for CTRL-X/A can be improved (#29590)

Problem:  signed number detection for CTRL-X/A can be improved
          (Chris Patuzzo)
Solution: Add the new "blank" value for the 'nrformat' setting. This
          will make Vim assume a signed number only if there is a blank
          in front of the sign.
          (distobs)

fixes: vim/vim#15033
closes: vim/vim#15110

https://github.com/vim/vim/commit/25ac6d67d92e0adda53b8d44b81c15031643ca1e

Co-authored-by: distobs <cuppotatocake@gmail.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/src/nvim/options.lua b/src/nvim/options.lua
index 365679261c..6e317a426c 100644
--- a/src/nvim/options.lua
+++ b/src/nvim/options.lua
@@ -5717,6 +5717,20 @@ return {
         	    (without "unsigned" it would become "9-2019").
         	    Using CTRL-X on "0" or CTRL-A on "18446744073709551615"
         	    (2^64 - 1) has no effect, overflow is prevented.
+        blank	If included, treat numbers as signed or unsigned based on
+        	preceding whitespace. If a number with a leading dash has its
+        	dash immediately preceded by a non-whitespace character (i.e.,
+        	not a tab or a " "), the negative sign won't be considered as
+        	part of the number.  For example:
+        	    Using CTRL-A on "14" in "Carbon-14" results in "Carbon-15"
+        	    (without "blank" it would become "Carbon-13").
+        	    Using CTRL-X on "8" in "Carbon -8" results in "Carbon -9"
+        	    (because -8 is preceded by whitespace. If "unsigned" was
+        	    set, it would result in "Carbon -7").
+        	If this format is included, overflow is prevented as if
+        	"unsigned" were set. If both this format and "unsigned" are
+        	included, "unsigned" will take precedence.
+
         Numbers which simply begin with a digit in the range 1-9 are always
         considered decimal.  This also happens for numbers that are not
         recognized as octal or hex.