 							resolve(lines)
 					.finally(logs.unsubscribe)
 				.then (lines) ->
-					m.chai.expect(lines.length).to.equal(2)
+					m.chai.expect(lines).to.have.lengthOf(2)
 					m.chai.expect(lines).to.deep.match [{
 						message: 'Old message'
 					}, {

							.catch(reject)
					.finally(logs.unsubscribe)
				.then (lines) ->
					m.chai.expect(lines.length).to.equal(2)
					m.chai.expect(lines).to.deep.match [{
						message: 'Existing message'
					}, {

						.then ->
							resolve(lines)
				.then (lines) ->
					m.chai.expect(lines).to.have.lengthOf(0)
