fibonacci spec and throw on too large of input.

Author: JakeHP

src/others/fibonacci.js

@@ -19,6 +19,9 @@
   'use strict';
 
   function fibonacci (n) {
+    if (n > 97) {
+      throw 'Input too large, results in inaccurate fibonacci value.';
+    }
     var n1 = 0;
     var n2 = 1;
     var aux;

test/others/fibonacci.spec.js

@@ -0,0 +1,28 @@
+'use strict';
+
+var mod = require('../../src/others/fibonacci.js');
+var fibonacci = mod.fibonacci;
+
+describe('fibonacci algorithm', function () {
+  it('should return value 1 with input 1.', function () {
+    expect(fibonacci(1)).toBe(1);
+  });
+  it('should return value 1 with input 2.', function () {
+    expect(fibonacci(2)).toBe(1);
+  });
+  it('should return value 2 with input 3.', function () {
+    expect(fibonacci(3)).toBe(2);
+  });
+  it('should return value 3 with input 4.', function () {
+    expect(fibonacci(4)).toBe(3);
+  });
+  it('should return value 5 with input 5.', function () {
+    expect(fibonacci(5)).toBe(5);
+  });
+  it('should be 83621143489848422977 with input 97.', function () {
+    expect(fibonacci(97)).toBe(83621143489848422977);
+  });
+  it('should throw when input is too large.', function () {
+    expect(function () {fibonacci(98)}).toThrow('Input too large, results in inaccurate fibonacci value.');
+  });
+});