Weird bash parameter expansion test behavior

testparams.bash

#!/bin/bash

bash --version
# My repro is on GNU bash, version 4.3.30(1)-release (x86_64-pc-linux-gnu)

echo
echo "unset"
test 'foo123' -eq 0 && echo "test: true" || echo "test: false"
[ 'foo123' -eq 0 ] && echo "[: true" || echo "[: false"
[[ 'foo123' -eq 0 ]] && echo "[[: true" || echo "[[: false"

echo
echo "=0"
foo123=0
test 'foo123' -eq 0 && echo "test: true" || echo "test: false"
[ 'foo123' -eq 0 ] && echo "[: true" || echo "[: false"
[[ 'foo123' -eq 0 ]] && echo "[[: true" || echo "[[: false"

echo
echo "=1"
foo123=1
test 'foo123' -eq 0 && echo "test: true" || echo "test: false"
[ 'foo123' -eq 0 ] && echo "[: true" || echo "[: false"
[[ 'foo123' -eq 0 ]] && echo "[[: true" || echo "[[: false"