Add offset snippet

scripts/web.js

@@ -54,7 +54,7 @@ const snippetsPath = './snippets',
 // Set variables for script
 let snippets = {},
   archivedSnippets = {},
-  beginnerSnippetNames = ['everyNth', 'filterNonUnique', 'last', 'maxN', 'minN', 'nthElement', 'sample', 'similarity', 'tail', 'currentURL', 'hasClass', 'getMeridiemSuffixOfInteger', 'factorial', 'fibonacci', 'gcd', 'isDivisible', 'isEven', 'isPrime', 'lcm', 'randomIntegerInRange', 'sum', 'reverseString', 'truncateString'],
+  beginnerSnippetNames = ['everyNth', 'filterNonUnique', 'last', 'maxN', 'minN', 'nthElement', 'offset', 'sample', 'similarity', 'tail', 'currentURL', 'hasClass', 'getMeridiemSuffixOfInteger', 'factorial', 'fibonacci', 'gcd', 'isDivisible', 'isEven', 'isPrime', 'lcm', 'randomIntegerInRange', 'sum', 'reverseString', 'truncateString'],
   startPart = '',
   endPart = '',
   output = '',

snippets/offset.md

@@ -0,0 +1,16 @@
+### offset
+
+Moves the specified amount of elements to the end of the array.
+
+Use `Array.slice()` twice to get the elements after the specified index and the elements before that.
+Use the spread operator(`...`) to combine the two into one array.
+If `offset` is negative, the elements will be moved from end to start.
+
+```js
+const offset = (arr, offset) => [...arr.slice(offset), ...arr.slice(0, offset)];
+```
+
+```js
+offset([1, 2, 3, 4, 5], 2); // [3, 4, 5, 1, 2]
+offset([1, 2, 3, 4, 5], -2); // [4, 5, 1, 2, 3]
+```

tag_database

@@ -171,6 +171,7 @@ objectFromPairs:object,array
 objectToPairs:object,array
 observeMutations:browser,event,advanced
 off:browser,event
+offset:array
 omit:object,array
 omitBy:object,array,function
 on:browser,event

test/offset/offset.js

@@ -0,0 +1,2 @@
+const offset = (arr, offset) => [...arr.slice(offset), ...arr.slice(0, offset)];
+module.exports = offset;

test/offset/offset.test.js

@@ -0,0 +1,19 @@
+const test = require('tape');
+const offset = require('./offset.js');
+
+test('Testing offset', (t) => {
+  //For more information on all the methods supported by tape
+  //Please go to https://github.com/substack/tape
+  t.true(typeof offset === 'function', 'offset is a Function');
+  t.deepEqual(offset([1, 2, 3, 4, 5], 0), [1, 2, 3, 4, 5], 'Offset of 0 returns the same array.');
+  t.deepEqual(offset([1, 2, 3, 4, 5], 2), [3, 4, 5, 1, 2], 'Offset > 0 returns the offsetted array.');
+  t.deepEqual(offset([1, 2, 3, 4, 5], -2), [4, 5, 1, 2, 3], 'Offset < 0 returns the reverse offsetted array.');
+  t.deepEqual(offset([1, 2, 3, 4, 5], 6),[1, 2, 3, 4, 5], 'Offset greater than the length of the array returns the same array.');
+  t.deepEqual(offset([1, 2, 3, 4, 5], -6), [1, 2, 3, 4, 5], 'Offset less than the negative length of the array returns the same array.');
+  t.deepEqual(offset([], 3), [], 'Offsetting empty array returns an empty array.');
+  //t.deepEqual(offset(args..), 'Expected');
+  //t.equal(offset(args..), 'Expected');
+  //t.false(offset(args..), 'Expected');
+  //t.throws(offset(args..), 'Expected');
+  t.end();
+});