From 66a8a5cfd513c58aa504c110f3bcd05626dc018b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christian=20K=C3=BChl?= <c.kuehl@micromata.de>
Date: Sat, 20 Oct 2018 13:48:51 +0200
Subject: [PATCH] add assertions isDivisibleByFive and containsFive

---
 README.md |  6 ++++++
 five.js   | 15 +++++++++++++++
 test.js   | 16 ++++++++++++++++
 3 files changed, 37 insertions(+)

diff --git a/README.md b/README.md
index addc66f6..f0a6a178 100644
--- a/README.md
+++ b/README.md
@@ -147,6 +147,12 @@ five.base(3); // 12
 ##### Assertion
 ```javascript
 five.isFive(10); // false
+five.isDivisibleByFive(8); // false
+five.isDivisibleByFive(15); // true
+five.containsFive(154); // true
+five.containsFive('this string contains 5, or not?'); // true
+five.containsFive([ 2, 5, 17 ]); // true
+five.containsFive([ 8, 14, 53 ]); // true
 ```
 
 ##### Filter, Map and Reduce
diff --git a/five.js b/five.js
index 90507e66..add1e5f7 100755
--- a/five.js
+++ b/five.js
@@ -135,6 +135,21 @@
   five.high = function() { return "o/"; };
 
   five.isFive = function(a) { return a === five(); };
+  
+  five.isDivisibleByFive = function(number) {
+    if (typeof number !== 'number') return false;
+    return number % five() === 0;
+  };
+  
+  five.containsFive = function(candidate) {
+    if (!candidate) return false;
+    
+    if (Object.prototype.toString.call(candidate) === '[object Array]') {
+      candidate = candidate.map(function(item) { return item.toString();}).join(' ');
+    }
+    
+    return candidate.toString().indexOf('5') !== -1;
+  }
 
   five.map = function(array) { return array.map(five); };
   five.filter = function(array) { return array.filter(five.isFive); };
diff --git a/test.js b/test.js
index 63ee6cc8..f201e639 100755
--- a/test.js
+++ b/test.js
@@ -132,6 +132,22 @@ assert.equal(five.funk(), '5 bad boys with the power to rock you', 'A funked fiv
 assert.equal(true, five.isFive(five()));
 assert.equal(false, five.isFive(10));
 
+assert.equal(false, five.isDivisibleByFive('foo'));
+assert.equal(true, five.isDivisibleByFive(five()));
+assert.equal(true, five.isDivisibleByFive(10));
+assert.equal(false, five.isDivisibleByFive(42));
+
+assert.equal(true, five.containsFive(153));
+assert.equal(true, five.containsFive('this string contains number 5, for sure!'));
+assert.equal(true, five.containsFive([1, 6, 15, 3]));
+assert.equal(false, five.containsFive());
+assert.equal(false, five.containsFive(null));
+assert.equal(false, five.containsFive(''));
+assert.equal(false, five.containsFive(false));
+assert.equal(false, five.containsFive(143));
+assert.equal(false, five.containsFive('this string does not contain...'));
+assert.equal(false, five.containsFive([1, 6, 8, 3]));
+
 assert.equal(JSON.stringify([5, 5]), JSON.stringify(five.filter([5, true, 5])));
 assert.equal(JSON.stringify([5, 5, 5]), JSON.stringify(five.map([1, 2, 3])));
 assert.equal(5, five.reduce([1, 2, 3]));