From bc6c8633c1c2b37e0c738abb16546f5d6a8dba8d Mon Sep 17 00:00:00 2001
From: simov <simeonvelichkov@gmail.com>
Date: Wed, 7 Feb 2018 11:17:57 +0200
Subject: [PATCH] Shorter stableSort function + use const

---
 snippets/stableSort.md             | 12 +++++-------
 test/stableSort/stableSort.js      |  6 ++----
 test/stableSort/stableSort.test.js |  8 ++++----
 3 files changed, 11 insertions(+), 15 deletions(-)

diff --git a/snippets/stableSort.md b/snippets/stableSort.md
index 929b34f09..96b352b08 100644
--- a/snippets/stableSort.md
+++ b/snippets/stableSort.md
@@ -6,24 +6,22 @@ Use `Array.map()` to pair each element of the input array with its corresponding
 Returns new array without modifying the initial one.
 
 ```js
-var stableSort = (arr, compare) =>
+const stableSort = (arr, compare) =>
   arr
     .map((item, index) => ({ item, index }))
-    .sort((a, b) =>
-      ((result = compare(a.item, b.item)) => (result !== 0 ? result : a.index - b.index))()
-    )
+    .sort((a, b) => compare(a.item, b.item) || a.index - b.index)
     .map(({ item }) => item);
 ```
 
 ```js
-var str = 'abcdefghijklmnopqrstuvwxyz';
-var compare = (a, b) => ~~(str.indexOf(b) / 2.3) - ~~(str.indexOf(a) / 2.3);
+const str = 'abcdefghijklmnopqrstuvwxyz';
+const compare = (a, b) => ~~(str.indexOf(b) / 2.3) - ~~(str.indexOf(a) / 2.3);
 
 // default Array.sort() is unstable in Chrome and NodeJS + modifies the input array
 var arr1 = str.split('');
 console.log(arr1.sort(compare).join('') === 'xyzvwtursopqmnklhijfgdeabc'); // false
 
 // stable sort + returns new array
-var arr2 = str.split('');
+const arr2 = str.split('');
 console.log(stableSort(arr2, compare).join('') === 'xyzvwtursopqmnklhijfgdeabc'); // true
 ```
diff --git a/test/stableSort/stableSort.js b/test/stableSort/stableSort.js
index d5b5db0c8..452d6b726 100644
--- a/test/stableSort/stableSort.js
+++ b/test/stableSort/stableSort.js
@@ -1,8 +1,6 @@
-var stableSort = (arr, compare) =>
+const stableSort = (arr, compare) =>
 arr
 .map((item, index) => ({ item, index }))
-.sort((a, b) =>
-((result = compare(a.item, b.item)) => (result !== 0 ? result : a.index - b.index))()
-)
+.sort((a, b) => compare(a.item, b.item) || a.index - b.index)
 .map(({ item }) => item);
 module.exports = stableSort;
\ No newline at end of file
diff --git a/test/stableSort/stableSort.test.js b/test/stableSort/stableSort.test.js
index 50e1bbe6b..7c41e06f3 100644
--- a/test/stableSort/stableSort.test.js
+++ b/test/stableSort/stableSort.test.js
@@ -12,11 +12,11 @@ test('Testing stableSort', (t) => {
   
   // test if js engine's Array#sort implementation is stable
   // https://gist.github.com/leeoniya/5816476
-  var str = 'abcdefghijklmnopqrstuvwxyz';
-  var compare = (a, b) => ~~(str.indexOf(b) / 2.3) - ~~(str.indexOf(a) / 2.3);
+  const str = 'abcdefghijklmnopqrstuvwxyz';
+  const compare = (a, b) => ~~(str.indexOf(b) / 2.3) - ~~(str.indexOf(a) / 2.3);
 
-  var input = str.split('');
-  var output = stableSort(input, compare);
+  const input = str.split('');
+  const output = stableSort(input, compare);
 
   t.equal(output.join(''), 'xyzvwtursopqmnklhijfgdeabc');
   t.notDeepEqual(input, output);