From b129b46c0d158bf3da0d765053628d271d2a0571 Mon Sep 17 00:00:00 2001
From: Angelos Chalaris <chalarangelo@gmail.com>
Date: Wed, 18 Jul 2018 21:02:42 +0300
Subject: [PATCH] Tags and tests

---
 snippets/uniqueElementsByRight.md             |  2 +-
 tag_database                                  |  3 ++
 test/filterNonUniqueBy/filterNonUniqueBy.js   |  3 ++
 .../filterNonUniqueBy.test.js                 | 32 +++++++++++++++++++
 test/uniqueElementsBy/uniqueElementsBy.js     |  6 ++++
 .../uniqueElementsBy/uniqueElementsBy.test.js | 32 +++++++++++++++++++
 .../uniqueElementsByRight.js                  |  6 ++++
 .../uniqueElementsByRight.test.js             | 32 +++++++++++++++++++
 8 files changed, 115 insertions(+), 1 deletion(-)
 create mode 100644 test/filterNonUniqueBy/filterNonUniqueBy.js
 create mode 100644 test/filterNonUniqueBy/filterNonUniqueBy.test.js
 create mode 100644 test/uniqueElementsBy/uniqueElementsBy.js
 create mode 100644 test/uniqueElementsBy/uniqueElementsBy.test.js
 create mode 100644 test/uniqueElementsByRight/uniqueElementsByRight.js
 create mode 100644 test/uniqueElementsByRight/uniqueElementsByRight.test.js

diff --git a/snippets/uniqueElementsByRight.md b/snippets/uniqueElementsByRight.md
index 42b351438..791c9621a 100644
--- a/snippets/uniqueElementsByRight.md
+++ b/snippets/uniqueElementsByRight.md
@@ -7,7 +7,7 @@ The comparator function takes two arguments: the values of the two elements bein
 
 ```js
 const uniqueElementsByRight = (arr, fn) =>
-	arr.reduce((acc, v) => {
+	arr.reduceRight((acc, v) => {
 		if (!acc.some(x => fn(v, x))) acc.push(v);
 		return acc;
 	}, []);
diff --git a/tag_database b/tag_database
index 0f5c9037d..bb2dfb23c 100644
--- a/tag_database
+++ b/tag_database
@@ -73,6 +73,7 @@ extendHex:utility,string
 factorial:math,recursion
 fibonacci:math,array
 filterNonUnique:array
+filterNonUniqueBy:array,function
 findKey:object,function
 findLast:array
 findLastIndex:array,function
@@ -298,6 +299,8 @@ union:array,math
 unionBy:array,function
 unionWith:array,function
 uniqueElements:array
+uniqueElementsBy:array,function
+uniqueElementsByRight:array,function
 untildify:node,string
 unzip:array
 unzipWith:array,function,advanced
diff --git a/test/filterNonUniqueBy/filterNonUniqueBy.js b/test/filterNonUniqueBy/filterNonUniqueBy.js
new file mode 100644
index 000000000..00bf31797
--- /dev/null
+++ b/test/filterNonUniqueBy/filterNonUniqueBy.js
@@ -0,0 +1,3 @@
+const filterNonUniqueBy = (arr, fn) =>
+arr.filter((v, i) => arr.every((x, j) => i == j == fn(v, x, i, j)));
+module.exports = filterNonUniqueBy;
\ No newline at end of file
diff --git a/test/filterNonUniqueBy/filterNonUniqueBy.test.js b/test/filterNonUniqueBy/filterNonUniqueBy.test.js
new file mode 100644
index 000000000..b73fb8f26
--- /dev/null
+++ b/test/filterNonUniqueBy/filterNonUniqueBy.test.js
@@ -0,0 +1,32 @@
+const expect = require('expect');
+const filterNonUniqueBy = require('./filterNonUniqueBy.js');
+
+test('filterNonUniqueBy is a Function', () => {
+  expect(filterNonUniqueBy).toBeInstanceOf(Function);
+});
+
+test('filterNonUniqueBy works for properties', () => {
+  expect(filterNonUniqueBy(
+  	[
+  		{ id: 0, value: 'a' },
+  		{ id: 1, value: 'b' },
+  		{ id: 2, value: 'c' },
+  		{ id: 1, value: 'd' },
+  		{ id: 0, value: 'e' },
+  	],
+  	(a, b) => a.id == b.id
+  )).toEqual([ { id: 2, value: 'c' } ]);
+});
+
+test('filterNonUniqueBy works for nested properties', () => {
+  expect(filterNonUniqueBy(
+  	[
+  		{ id: 0, value: 'a', n: {p: 0} },
+  		{ id: 1, value: 'b', n: {p: 1} },
+  		{ id: 2, value: 'c', n: {p: 2} },
+  		{ id: 1, value: 'd', n: {p: 0} },
+  		{ id: 0, value: 'e', n: {p: 1} },
+  	],
+  	(a, b) => a.id == b.id
+  )).toEqual([ { id: 2, value: 'c', n: {p: 2} } ]);
+});
diff --git a/test/uniqueElementsBy/uniqueElementsBy.js b/test/uniqueElementsBy/uniqueElementsBy.js
new file mode 100644
index 000000000..60634739e
--- /dev/null
+++ b/test/uniqueElementsBy/uniqueElementsBy.js
@@ -0,0 +1,6 @@
+const uniqueElementsBy = (arr, fn) =>
+arr.reduce((acc, v) => {
+if (!acc.some(x => fn(v, x))) acc.push(v);
+return acc;
+}, []);
+module.exports = uniqueElementsBy;
\ No newline at end of file
diff --git a/test/uniqueElementsBy/uniqueElementsBy.test.js b/test/uniqueElementsBy/uniqueElementsBy.test.js
new file mode 100644
index 000000000..aa5293336
--- /dev/null
+++ b/test/uniqueElementsBy/uniqueElementsBy.test.js
@@ -0,0 +1,32 @@
+const expect = require('expect');
+const uniqueElementsBy = require('./uniqueElementsBy.js');
+
+test('uniqueElementsBy is a Function', () => {
+  expect(uniqueElementsBy).toBeInstanceOf(Function);
+});
+
+test('uniqueElementsBy works for properties', () => {
+  expect(uniqueElementsBy(
+  	[
+  		{ id: 0, value: 'a' },
+  		{ id: 1, value: 'b' },
+  		{ id: 2, value: 'c' },
+  		{ id: 1, value: 'd' },
+  		{ id: 0, value: 'e' },
+  	],
+  	(a, b) => a.id == b.id
+  )).toEqual([ { id: 0, value: 'a' }, { id: 1, value: 'b' }, { id: 2, value: 'c' } ]);
+});
+
+test('uniqueElementsBy works for nested properties', () => {
+  expect(uniqueElementsBy(
+  	[
+  		{ id: 0, value: 'a', n: {p: 0} },
+  		{ id: 1, value: 'b', n: {p: 1} },
+  		{ id: 2, value: 'c', n: {p: 2} },
+  		{ id: 1, value: 'd', n: {p: 0} },
+  		{ id: 0, value: 'e', n: {p: 1} },
+  	],
+  	(a, b) => a.id == b.id
+  )).toEqual([ { id: 0, value: 'a', n: {p: 0} }, { id: 1, value: 'b', n: {p: 1} }, { id: 2, value: 'c', n: {p: 2} } ]);
+});
diff --git a/test/uniqueElementsByRight/uniqueElementsByRight.js b/test/uniqueElementsByRight/uniqueElementsByRight.js
new file mode 100644
index 000000000..3b6975a4b
--- /dev/null
+++ b/test/uniqueElementsByRight/uniqueElementsByRight.js
@@ -0,0 +1,6 @@
+const uniqueElementsByRight = (arr, fn) =>
+arr.reduceRight((acc, v) => {
+if (!acc.some(x => fn(v, x))) acc.push(v);
+return acc;
+}, []);
+module.exports = uniqueElementsByRight;
\ No newline at end of file
diff --git a/test/uniqueElementsByRight/uniqueElementsByRight.test.js b/test/uniqueElementsByRight/uniqueElementsByRight.test.js
new file mode 100644
index 000000000..aeed58d36
--- /dev/null
+++ b/test/uniqueElementsByRight/uniqueElementsByRight.test.js
@@ -0,0 +1,32 @@
+const expect = require('expect');
+const uniqueElementsByRight = require('./uniqueElementsByRight.js');
+
+test('uniqueElementsByRight is a Function', () => {
+  expect(uniqueElementsByRight).toBeInstanceOf(Function);
+});
+
+test('uniqueElementsByRight works for properties', () => {
+  expect(uniqueElementsByRight(
+  	[
+  		{ id: 0, value: 'a' },
+  		{ id: 1, value: 'b' },
+  		{ id: 2, value: 'c' },
+  		{ id: 1, value: 'd' },
+  		{ id: 0, value: 'e' },
+  	],
+  	(a, b) => a.id == b.id
+  )).toEqual([ { id: 0, value: 'e' }, { id: 1, value: 'd' }, { id: 2, value: 'c' } ]);
+});
+
+test('uniqueElementsByRight works for nested properties', () => {
+  expect(uniqueElementsByRight(
+  	[
+  		{ id: 0, value: 'a', n: {p: 0} },
+  		{ id: 1, value: 'b', n: {p: 1} },
+  		{ id: 2, value: 'c', n: {p: 2} },
+  		{ id: 1, value: 'd', n: {p: 0} },
+  		{ id: 0, value: 'e', n: {p: 1} },
+  	],
+  	(a, b) => a.id == b.id
+  )).toEqual([ { id: 0, value: 'e', n: {p: 1} }, { id: 1, value: 'd', n: {p: 0} }, { id: 2, value: 'c', n: {p: 2} } ]);
+});