Node.js test with expresso

I tried to use expresso to test my project. I have installed it with command

sudo npm install --save expresso

and it worked for me. Than I decided to test it in created test.js file with code

var assert = require('assert');
assert.equal(6, 'foobar'.length);

I run it with command expresso ./test.js as was written in example But I have got result

No command 'expresso' found, did you mean:
Command 'extresso' from package 'icoutils' (universe)
Command 'express' from package 'node-express' (universe)
expresso: command not found

Can anyone help me, please? Thank you in advance!