msys-docker.sh

#!/bin/bash

# Workaround docker wrapper for git-bash/Msys/Cygwin quirks
# Copy this to ~/bin/docker or /usr/local/bin/docker

set -euo pipefail

export MSYS_NO_PATHCONV=1
export MSYS2_ARG_CONV_EXCL='*' 
os="$(uname -o)"
realdocker="$(which -a docker | grep -v "$(readlink -f "$0")" | head -1)"
if [[ "$os" == "Msys" ]] || [[ "$os" == "Cygwin" ]]; then
    printf "%s\0" "$@" > /tmp/args.txt
    # --tty or -t requires winpty
    if grep -ZE '^--tty|^-[^-].*t|^-t.*' /tmp/args.txt; then
        exec winpty /bin/bash -c "xargs -0a /tmp/args.txt '$realdocker'"
    fi
fi
exec "$realdocker" "$@"

Isn't there a "return" missing after line 16?

@DrVanScott No. The exec builtin transfers control to another program (winpty).