spyny

A tiny spy library for Node.js.

spy([callback])

Use the spy function to create a new spy.

var spy = require('spyny');
var mySpy = spy();

You can also provide a callback to be ran when the spy is called. It will recieve all arguments that are passed to the spy.

var mySpy = spy(function(name) {
  return 'Hello, ' + name + '!';
});
 
console.log(mySpy('Dave'));
// Hello, Dave!

called

Check if a spy was called.

mySpy();
console.log(mySpy.called);
// true

callCount

Check how many times a spy was called.

mySpy();
mySpy();
console.log(mySpy.callCount);
// 2

callWith()

Alternative way of setting the spy callback.

mySpy.callWith(function(name) {
  return 'Yo, ' + name + '!';
});
 
console.log(mySpy('Dave'));
// Yo, Dave!

getCall()

Get the details of a specific call.

mySpy('yo!');
console.log(mySpy.getCall(0));
// {
//   args: ['yo!']
// }

reset()

Flush all previous call data.

mySpy();
mySpy.reset();
console.log(mySpy.called);
// false

returns()

Assign a return value for the spy.

mySpy.returns('Howdy!');
console.log(mySpy());
// Howdy!

===

spy.on(obj, method, [callback])

Spy on an objects method. Contains all properties and methods of spy().

var Dave = {
  greet: function(person) {
    return 'Hello, ' + person + '!';
  }
};
 
spy.on(Dave, 'greet').returns('Howdy');
console.log(Dave.greet('Gabe'));
// Howdy

You can also pass in a callback to be invoked.

spy.on(Dave, 'greet', function(person) {
  return 'Howdy, ' + person + '.';
});
 
console.log(Dave.greet('Gabe'));
// Howdy, Gabe.

restore()

Restore a method to its previous state.

spy.on(Dave, 'greet');
Dave.greet.restore();
console.log(Dave.greet('Gabe'));
// Hello, Gabe!

passthrough()

When called it instructs the spy to use the original method as the callback.

spy.on(Dave, 'greet').passthrough();
console.log(Dave.greet('Gabe'));
// Hello, Gabe!
console.log(Dave.greet.getCall(0));
// {
//   args: ['Gabe']
// }

===

spy.sandbox()

Create a sandbox object to contain all of your spies. Useful for mass cleanups.

var sandbox = require('spyny').sandbox();
var spy = sandbox.spy;

spy([callback])

Creates a spy contained within the sandbox. Contains the same properties and methods as a normal spy.

var sandbox = require('spyny').sandbox();
var spy = sandbox.spy;
var mySpy = spy();
 
mySpy();
console.log(mySpy.called);
// true

spy.on(obj, method, [callback])

Creates a spy for an object's method within the sandbox. Contains the same properties and methods as a normal spy.on()

var sandbox = require('spyny').sandbox();
var spy = sandbox.spy;
 
spy.on(Dave, 'greet').passthrough();
console.log(Dave.greet.called);
// false

reset()

Resets all spies within the sandbox.

var sandbox = require('spyny').sandbox();
var spy = sandbox.spy;
var spy1 = spy();
var spy2 = spy();
 
spy1();
spy2();
spy2();
 
sandbox.reset();
 
console.log(spy1.called);
// false
console.log(spy2.callCount);
// 0

restore()

Restores all spies created via spy.on() to previous state.

var sandbox = require('spyny').sandbox();
var spy = sandbox.spy;
 
spy.on(Dave, 'greet', function() {
  return 'asdf!';
});
 
sandbox.restore();
console.log(Dave.greet('Gabe'));
// Hello, Gabe!

flush()

Clear all cached spies from the sandbox. Note: this does not restore/reset spies, this simply clears them all from the sandbox cache.

var sandbox = require('spyny').sandbox();
var spy = sandbox.spy;
 
spy.on(Dave, 'greet', function() {
  return 'hi';
});
 
sandbox.flush();
sandbox.restore(); // `Dave.greet` is still a spy
 
 

License

ISC