I find echo -n doesn't work for string less than 3 characters, printf doesn't work either.
❯ fish --version
fish, version 4.3.2
❯ echo $version
4.3.2
❯ uname
Linux
❯ echo $TERM
foot
❯ sh -c 'env HOME=$(mktemp -d) XDG_CONFIG_HOME= XDG_DATA_DIRS= fish'
hjl@eos /h/hjl> echo -n 1
hjl@eos /h/hjl> echo -n 11
hjl@eos /h/hjl> echo -n 111
111⏎
hjl@eos /h/hjl> printf "1"
hjl@eos /h/hjl> printf "11"
hjl@eos /h/hjl> printf "111"
111⏎