Pattern: Use of string as argument to numerical operator
Issue: -
ShellCheck found a string used as an argument to a numerical operator like -eq, -ne, -lt, -ge. Such strings will be treated as arithmetic expressions, meaning n will refer to a variable $n, and 24/12 will be evaluated into 2.
In the problematic example, the intention was instead to compare "n" as a string, so it should use the equivalent string operator instead, in this case =.
Example of incorrect code:
read -p "Continue? [y/n] " var
[ "$var" -eq "n" ] && exit 1Example of correct code:
#read -p "Continue? [y/n] " var
[ "$var" = "n" ] && exit 1