[Feature request] Entering a wrong ES version should fail

[AlexandreBonneau]

Requested Update

Currently, using es-check foo dist/*.js returns ES-Check: there were no ES version matching errors! 🎉

However you could assume that if the dev mistyped foo instead of es4, he could also mistype se7 instead of es7.
I think es-check should throw an error when it does not recognize a valid ecmaVersion argument (see the default behavior in

es-check/index.js

Line 74 in b7a40f2

switch (v) {

).

Why Is This Update Needed?

Devs that check their ES version do not need to be handled; lets tell them the harsh truth; they made a typo!

Are There Examples Of This Requested Update Elsewhere?

Nope, but issue #40 could have been avoided perhaps?
Specially if when such an error is detected, you could display a usage info with all the possible ecmaVersion.