--- title: we are testing tests | daily.dev description: Mutation testing is a tool to assess the quality of tests by modifying small pieces of code and checking the impact on the tests. The Infection framework is... canonical: https://daily.dev/posts/we-are-testing-tests-bwtvdjvvd twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: we are testing tests | daily.dev og:description: Mutation testing is a tool to assess the quality of tests by modifying small pieces of code and checking the impact on the tests. The Infection framework is... og:url: https://daily.dev/posts/we-are-testing-tests-bwtvdjvvd og:image: https://api.daily.dev/og/posts/bwTVdJvvD.png og:image:alt: we are testing tests og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # we are testing tests **[Community Picks](https://daily.dev/sources/community)** · 20 min read · 5 upvotes · 0 comments ## Summary Mutation testing is a tool to assess the quality of tests by modifying small pieces of code and checking the impact on the tests. The Infection framework is popular for mutation testing in PHP. It uses AST (Abstract Syntax Tree) and a parser to create mutated code and execute tests. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: --- Tags: [#mutation-testing](https://daily.dev/tags/mutation-testing), [#php](https://daily.dev/tags/php), [#testing](https://daily.dev/tags/testing) [View this post on daily.dev](https://daily.dev/posts/we-are-testing-tests-bwtvdjvvd) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"we are testing tests","url":"https://daily.dev/posts/we-are-testing-tests-bwtvdjvvd","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/we-are-testing-tests-bwtvdjvvd"},"datePublished":"2024-01-25T20:02:37.483Z","dateModified":"2026-04-17T02:12:42.497Z","description":"Mutation testing is a tool to assess the quality of tests by modifying small pieces of code and checking the impact on the tests. The Infection framework is...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/aa5822f53f592b9084755c09b017ac50?_a=AQAEufR","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/aa5822f53f592b9084755c09b017ac50?_a=AQAEufR","isAccessibleForFree":true,"articleSection":"Community Picks","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Community Picks","logo":"https://media.daily.dev/image/upload/t_logo,f_auto/v1655817725/logos/community","url":"https://daily.dev/sources/community"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/we-are-testing-tests-bwtvdjvvd","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":5},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"mutation-testing,php,testing","timeRequired":"PT20M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Community Picks","item":"https://daily.dev/sources/community"},{"@type":"ListItem","position":3,"name":"we are testing tests"}]} ```