I had a simmiliar solution.
One little detail: You don't need the else block when you are returning in the if block.

There is in test "The more he saw the less he spoke" double spaces (in JS version).

In JS too.

Print the input, those are two letters words, you're missing the n on both of them.

Please excuse my ignorance but I'm not sure from the below what the [n 97n] part of this expected outcome is actually referring to? I can't think what random input would create this output.

expected:<...dl 111lw 108dvei 105[n 97n] 111ka>
 but was:<...dl 111lw 108dvei 105[ 97] 111ka>