bump_version returns incorrect result

[polRk]

./semver.sh "1.0.0" bump_major
1.0.0

[martinhbramwell]

Please run these commands and compare with the results below:

lsb_release -a
bash --version
declare MAJOR=1
echo $((MAJOR + 1))

erpdev@fossa:~/projects/semver_shell$ lsb_release -a
No LSB modules are available.
Distributor ID:	Ubuntu
Description:	Ubuntu 20.04.1 LTS
Release:	20.04
Codename:	focal
erpdev@fossa:~/projects/semver_shell$ bash --version
GNU bash, version 5.0.17(1)-release (x86_64-pc-linux-gnu)
Copyright (C) 2019 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>

This is free software; you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
erpdev@fossa:~/projects/semver_shell$ 
erpdev@fossa:~/projects/semver_shell$ declare  MAJOR=1
erpdev@fossa:~/projects/semver_shell$ echo $((MAJOR + 1))
2