minispy

Simple test spy utilities, framework agnostic. Inspection API similar to sinon.js.

Installation

Component

$ component install ericgj/minispy

Node.js

$ npm install minispy

Examples

To use a spy itself as a simple callback function

var spy = Spy();
someFunctionWithCallback("parameter", spy.watch);
assert(spy.called());

To wrap a callback function with a spy

var spy = Spy(callback);
someFunctionWithCallback("parameter", spy.watch);
assert.equal(spy.lastCall().returnValue, callback());

To stub a method call on an existing object with a spy

var spy = Spy.stub(obj, "method", function(){
  obj.method();
});
assert(spy.called());

Note that stub does not pass through the method call but intercepts it. The injected spy thus acts more like a classical mock.

To wrap a method call on an existing object with a spy

var spy = Spy.wrap(obj, "method", function(){
  obj.method();
});
assert.equal(spy.lastCall().returnValue, obj.method());

API

The API for inspecting spy results is similar to sinon.js, except using methods instead of properties (e.g. spy.called() vs spy.called.

The following inspection methods from sinon.js are built-in:

• callCount
• called
• notCalled
• calledOnce
• calledExactly({Integer})
• firstCall
• lastCall
• getCall({Integer})
• calledWith(args...)
• alwaysCalledWith(args...)
• calledWithExactly(args...)
• alwaysCalledWithExactly(args...)
• neverCalledWith(args...)
• threw({null|String|Object})
• alwaysThrew({null|String|Object})
• returned({Object})
• alwaysReturned({Object})
• calledBefore({Spy})
• calledAfter({Spy})

Note that spy.calls() returns an enumerable, allowing for easily defined custom finders and chaining. For example, to select "the return values from all spied calls with at least one argument":

spy.calls().select('arguments.length > 0').map('returnValue');

License

MIT