fix: issue with filtering with property values of number 0 (#47)

* Fixes issue with filtering with property values of number 0

* Fixes null check

* Update index.js

.all-contributorsrc

@@ -95,6 +95,15 @@
         "test",
         "ideas"
       ]
+    },
+    {
+      "login": "pushpinder107",
+      "name": "pushpinder107",
+      "avatar_url": "https://avatars3.githubusercontent.com/u/9403361?v=4",
+      "profile": "https://github.com/pushpinder107",
+      "contributions": [
+        "code"
+      ]
     }
   ],
   "repoType": "github"

README.md

@@ -15,7 +15,7 @@
 [![downloads][downloads-badge]][npm-stat]
 [![MIT License][license-badge]][license]
 
-[![All Contributors](https://img.shields.io/badge/all_contributors-8-orange.svg?style=flat-square)](#contributors)
+[![All Contributors](https://img.shields.io/badge/all_contributors-9-orange.svg?style=flat-square)](#contributors)
 [![PRs Welcome][prs-badge]][prs]
 [![Donate][donate-badge]][donate]
 [![Code of Conduct][coc-badge]][coc]
@@ -273,7 +273,7 @@ Thanks goes to these people ([emoji key][emojis]):
 <!-- prettier-ignore -->
 | [<img src="https://avatars.githubusercontent.com/u/1500684?v=3" width="100px;"/><br /><sub><b>Kent C. Dodds</b></sub>](https://kentcdodds.com)<br />[💻](https://github.com/kentcdodds/match-sorter/commits?author=kentcdodds "Code") [📖](https://github.com/kentcdodds/match-sorter/commits?author=kentcdodds "Documentation") [🚇](#infra-kentcdodds "Infrastructure (Hosting, Build-Tools, etc)") [⚠️](https://github.com/kentcdodds/match-sorter/commits?author=kentcdodds "Tests") [👀](#review-kentcdodds "Reviewed Pull Requests") | [<img src="https://avatars.githubusercontent.com/u/8263298?v=3" width="100px;"/><br /><sub><b>Conor Hastings</b></sub>](http://conorhastings.com)<br />[💻](https://github.com/kentcdodds/match-sorter/commits?author=conorhastings "Code") [📖](https://github.com/kentcdodds/match-sorter/commits?author=conorhastings "Documentation") [⚠️](https://github.com/kentcdodds/match-sorter/commits?author=conorhastings "Tests") [👀](#review-conorhastings "Reviewed Pull Requests") | [<img src="https://avatars.githubusercontent.com/u/574806?v=3" width="100px;"/><br /><sub><b>Rogelio Guzman</b></sub>](https://github.com/rogeliog)<br />[📖](https://github.com/kentcdodds/match-sorter/commits?author=rogeliog "Documentation") | [<img src="https://avatars.githubusercontent.com/u/1416436?v=3" width="100px;"/><br /><sub><b>Claudéric Demers</b></sub>](http://ced.io)<br />[💻](https://github.com/kentcdodds/match-sorter/commits?author=clauderic "Code") [📖](https://github.com/kentcdodds/match-sorter/commits?author=clauderic "Documentation") [⚠️](https://github.com/kentcdodds/match-sorter/commits?author=clauderic "Tests") | [<img src="https://avatars3.githubusercontent.com/u/4150097?v=3" width="100px;"/><br /><sub><b>Kevin Davis</b></sub>](kevindav.us)<br />[💻](https://github.com/kentcdodds/match-sorter/commits?author=osfan501 "Code") [⚠️](https://github.com/kentcdodds/match-sorter/commits?author=osfan501 "Tests") | [<img src="https://avatars1.githubusercontent.com/u/19157735?v=3" width="100px;"/><br /><sub><b>Denver Chen</b></sub>](https://github.com/nfdjps)<br />[💻](https://github.com/kentcdodds/match-sorter/commits?author=nfdjps "Code") [📖](https://github.com/kentcdodds/match-sorter/commits?author=nfdjps "Documentation") [⚠️](https://github.com/kentcdodds/match-sorter/commits?author=nfdjps "Tests") | [<img src="https://avatars0.githubusercontent.com/u/12719057?v=4" width="100px;"/><br /><sub><b>Christian Ruigrok</b></sub>](http://ruigrok.info)<br />[🐛](https://github.com/kentcdodds/match-sorter/issues?q=author%3AChrisRu "Bug reports") [💻](https://github.com/kentcdodds/match-sorter/commits?author=ChrisRu "Code") [📖](https://github.com/kentcdodds/match-sorter/commits?author=ChrisRu "Documentation") |
 | :---: | :---: | :---: | :---: | :---: | :---: | :---: |
-| [<img src="https://avatars1.githubusercontent.com/u/2084833?v=4" width="100px;"/><br /><sub><b>Hozefa</b></sub>](https://github.com/hozefaj)<br />[🐛](https://github.com/kentcdodds/match-sorter/issues?q=author%3Ahozefaj "Bug reports") [💻](https://github.com/kentcdodds/match-sorter/commits?author=hozefaj "Code") [⚠️](https://github.com/kentcdodds/match-sorter/commits?author=hozefaj "Tests") [🤔](#ideas-hozefaj "Ideas, Planning, & Feedback") |
+| [<img src="https://avatars1.githubusercontent.com/u/2084833?v=4" width="100px;"/><br /><sub><b>Hozefa</b></sub>](https://github.com/hozefaj)<br />[🐛](https://github.com/kentcdodds/match-sorter/issues?q=author%3Ahozefaj "Bug reports") [💻](https://github.com/kentcdodds/match-sorter/commits?author=hozefaj "Code") [⚠️](https://github.com/kentcdodds/match-sorter/commits?author=hozefaj "Tests") [🤔](#ideas-hozefaj "Ideas, Planning, & Feedback") | [<img src="https://avatars3.githubusercontent.com/u/9403361?v=4" width="100px;"/><br /><sub><b>pushpinder107</b></sub>](https://github.com/pushpinder107)<br />[💻](https://github.com/kentcdodds/match-sorter/commits?author=pushpinder107 "Code") |
 
 <!-- ALL-CONTRIBUTORS-LIST:END -->
 

src/__tests__/index.js

@@ -111,6 +111,19 @@ const tests = {
       {first: 'not', second: 'not', third: 'not', fourth: 'match'},
     ],
   },
+  'can handle the number 0 as a property value': {
+    input: [
+      [
+        {name: 'A', age: 0},
+        {name: 'B', age: 1},
+        {name: 'C', age: 2},
+        {name: 'D', age: 3},
+      ],
+      '0',
+      {keys: ['age']},
+    ],
+    output: [{name: 'A', age: 0}],
+  },
   'can handle objected with nested keys': {
     input: [
       [

src/index.js

@@ -387,7 +387,8 @@ function getItemValues(item, key) {
     value = item[key]
   }
   // concat because `value` can be a string or an array
-  return value ? [].concat(value) : null
+  // eslint-disable-next-line
+  return value != null ? [].concat(value) : null
 }
 
 /**