Added unit tests for "parser.js" and "util.js"

test/unit/util.spec.js

@@ -0,0 +1,26 @@
+var util = require('../../src/util')
+var { expect } = require('chai')
+
+describe('util.js', () => {
+  describe('#inRange', () => {
+    it('Should return the source value (in the range)', () => {
+      let value = util.inRange(-10, 10, 0)
+      expect(value).to.equal(0)
+    })
+
+    it('Should not be equal to the source value (outside the range)', () => {
+      let value = util.inRange(-10, 10, -100)
+      expect(value).not.to.equal(-100)
+    })
+
+    it('Should replace source value with upper limit', () => {
+      let value = util.inRange(0, 10, 30)
+      expect(value).to.equal(10)
+    })
+
+    it('Should replace source value with lower limit', () => {
+      let value = util.inRange(1, 10, -1)
+      expect(value).to.equal(1)
+    })
+  })
+})