Add typecheck.js test (#184)

lib/typecheck.js

@@ -1,4 +1,3 @@
-// istanbul ignore file
 'use strict';
 
 var includes = require('lodash/includes');

test/typecheck.test.js

@@ -0,0 +1,35 @@
+'use strict';
+
+var check = require('../lib/typecheck');
+var isNumber = require('lodash/isNumber');
+
+describe('check', function() {
+    var errorMessage = 'It did not check correctly';
+
+    it('checks if it passes the function to check', function() {
+        var checkFn = check(function(n) {
+            return n === 5;
+        }, errorMessage);
+        expect(checkFn(5).pass).toBe(true);
+        expect(checkFn(5).error).toBeUndefined();
+        expect(checkFn(1).pass).toBe(false);
+        expect(checkFn(1).error).toBe(errorMessage);
+    });
+
+    it('checks it is one of', function() {
+        var checkIsOneOfFn = check.isOneOf([10, 30]);
+        expect(checkIsOneOfFn(10)).toBe(true);
+        expect(checkIsOneOfFn(30)).toBe(true);
+        expect(checkIsOneOfFn(33)).toBe(false);
+        expect(checkIsOneOfFn('ten')).toBe(false);
+    });
+
+    it('checks it is array of', function() {
+        var checkIsArrayOfNumberFn = check.isArrayOf(isNumber);
+        expect(checkIsArrayOfNumberFn([])).toBe(true);
+        expect(checkIsArrayOfNumberFn({})).toBe(false);
+        expect(checkIsArrayOfNumberFn('55,22')).toBe(false);
+        expect(checkIsArrayOfNumberFn([55, 22])).toBe(true);
+        expect(checkIsArrayOfNumberFn([55, '5', 22])).toBe(false);
+    });
+});