add tests/test_which.sh

tests/test_which.sh

+#!/bin/sh
+
+# support for direct run a play script
+if [ -x "../bin/epm" ] ; then
+    export PATH="$(realpath ../bin):$PATH"
+fi
+
+print_command_path2()
+{
+    a= type -fpP -- "$1" 2>/dev/null
+}
+
+
+for i in $(seq 1 100) ; do
+    #epm tool which which
+    #which which
+    print_command_path2 which
+done
+