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<!doctype html><html lang="en"><head><meta charset="UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=edge"><meta name="viewport" content="width=device-width,initial-scale=1"><meta name="generator" content="Rspress v1.20.1"><title data-rh="true">Testing environment - React Native Testing Library</title><meta data-rh="true" name="description" content="Helps you to write better tests with less effort."/><script>{const e=localStorage.getItem("rspress-theme-appearance"),t=window.matchMedia("(prefers-color-scheme: dark)").matches,a=e&&"auto"!==e?"dark"===e:t;document.documentElement.classList.toggle("dark",a),document.documentElement.style.colorScheme=a?"dark":"light"}</script><title>React Native Testing Library</title><meta property="og:url" content="https://callstack.github.io/react-native-testing-library/"><meta property="og:type" content="website"><meta property="og:title" content="React Native Testing Library"><meta property="og:description" content="Helps you to write better tests 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transition-opacity duration-300 hover:opacity-60"><img src="/react-native-testing-library/img/owl.png" alt="logo" id="logo" class="mr-4 rspress-logo"/><span>React Native Testing Library</span></a></div></div><div class="mt-1 sidebarContent_71eca"><div class="rspress-scrollbar" style="max-height:calc(100vh - var(--rp-nav-height) - 8px);overflow:auto"><nav class="pb-2"><section class="mt-0.5 block" style="margin-left:0"><div class="flex justify-between items-center menuItem_71eca" style="border-radius:0 var(--rp-radius) var(--rp-radius) 0;cursor:pointer"><h2 class="py-2 px-3 text-sm font-medium flex" style="font-size:14px;padding-left:24px;font-weight:bold"><span class="flex-center">Getting started</span></h2><div class="collapseContainer_71eca p-2 rounded-xl"><div style="cursor:pointer;transition:transform 0.2s ease-out;transform:rotate(90deg)"><svg width="1em" height="1em" viewBox="0 0 32 32"><path fill="currentColor" d="M22 16 12 26l-1.4-1.4 8.6-8.6-8.6-8.6L12 6z"></path></svg></div></div></div><div class="transition-all duration-300 ease-in-out" style="overflow:hidden"><div class="rspress-sidebar-group transition-opacity duration-500 ease-in-out" style="opacity:1;margin-left:12px"><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/start/intro"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Introduction</span></div></a></div><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/start/quick-start"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Quick Start</span></div></a></div></div></div></section><section class="mt-0.5 block" style="margin-left:0"><div class="flex justify-between items-center menuItem_71eca" style="border-radius:0 var(--rp-radius) var(--rp-radius) 0;cursor:pointer"><h2 class="py-2 px-3 text-sm font-medium flex" style="font-size:14px;padding-left:24px;font-weight:bold"><span class="flex-center">API reference</span></h2><div class="collapseContainer_71eca p-2 rounded-xl"><div style="cursor:pointer;transition:transform 0.2s ease-out;transform:rotate(90deg)"><svg width="1em" height="1em" viewBox="0 0 32 32"><path fill="currentColor" d="M22 16 12 26l-1.4-1.4 8.6-8.6-8.6-8.6L12 6z"></path></svg></div></div></div><div class="transition-all duration-300 ease-in-out" style="overflow:hidden"><div class="rspress-sidebar-group transition-opacity duration-500 ease-in-out" style="opacity:1;margin-left:12px"><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/api/render"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Render function</span></div></a></div><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/api/screen"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Screen object</span></div></a></div><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/api/queries"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Queries</span></div></a></div><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/api/jest-matchers"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Jest matchers</span></div></a></div><div><section class="mt-0.5 block" style="margin-left:18px"><div class="flex justify-between items-center menuItem_71eca" style="cursor:pointer"><h2 class="py-2 px-3 text-sm font-medium flex"><span class="flex-center">Triggering events</span></h2><div class="collapseContainer_71eca p-2 rounded-xl"><div style="cursor:pointer;transition:transform 0.2s ease-out;transform:rotate(90deg)"><svg width="1em" height="1em" viewBox="0 0 32 32"><path fill="currentColor" d="M22 16 12 26l-1.4-1.4 8.6-8.6-8.6-8.6L12 6z"></path></svg></div></div></div><div class="transition-all duration-300 ease-in-out" style="overflow:hidden"><div class="rspress-sidebar-group transition-opacity duration-500 ease-in-out" style="opacity:1;margin-left:0"><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/api/events/user-event"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>User Event</span></div></a></div><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/api/events/fire-event"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Fire Event</span></div></a></div></div></div></section></div><div><section class="mt-0.5 block" style="margin-left:18px"><div class="flex justify-between items-center menuItem_71eca" style="cursor:pointer"><h2 class="py-2 px-3 text-sm font-medium flex"><span class="flex-center">Miscellaneous</span></h2><div class="collapseContainer_71eca p-2 rounded-xl"><div style="cursor:pointer;transition:transform 0.2s ease-out;transform:rotate(90deg)"><svg width="1em" height="1em" viewBox="0 0 32 32"><path fill="currentColor" d="M22 16 12 26l-1.4-1.4 8.6-8.6-8.6-8.6L12 6z"></path></svg></div></div></div><div class="transition-all duration-300 ease-in-out" style="overflow:hidden"><div class="rspress-sidebar-group transition-opacity duration-500 ease-in-out" style="opacity:1;margin-left:0"><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/api/misc/render-hook"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Render Hook function</span></div></a></div><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/api/misc/async"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Async utilities</span></div></a></div><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/api/misc/config"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Configuration</span></div></a></div><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/api/misc/accessibility"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Accessibility</span></div></a></div><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/api/misc/other"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Other helpers</span></div></a></div></div></div></section></div></div></div></section><section class="mt-0.5 block" style="margin-left:0"><div class="flex justify-between items-center menuItem_71eca" style="border-radius:0 var(--rp-radius) var(--rp-radius) 0;cursor:pointer"><h2 class="py-2 px-3 text-sm font-medium flex" style="font-size:14px;padding-left:24px;font-weight:bold"><span class="flex-center">Guides</span></h2><div class="collapseContainer_71eca p-2 rounded-xl"><div style="cursor:pointer;transition:transform 0.2s ease-out;transform:rotate(90deg)"><svg width="1em" height="1em" viewBox="0 0 32 32"><path fill="currentColor" d="M22 16 12 26l-1.4-1.4 8.6-8.6-8.6-8.6L12 6z"></path></svg></div></div></div><div class="transition-all duration-300 ease-in-out" style="overflow:hidden"><div class="rspress-sidebar-group transition-opacity duration-500 ease-in-out" style="opacity:1;margin-left:12px"><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/guides/how-to-query"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>How should I query?</span></div></a></div><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/guides/troubleshooting"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Troubleshooting</span></div></a></div><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/guides/faq"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>FAQ</span></div></a></div><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/guides/community-resources"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Community resources</span></div></a></div></div></div></section><section class="mt-0.5 block" style="margin-left:0"><div class="flex justify-between items-center menuItem_71eca" style="border-radius:0 var(--rp-radius) var(--rp-radius) 0;cursor:pointer"><h2 class="py-2 px-3 text-sm font-medium flex" style="font-size:14px;padding-left:24px;font-weight:bold"><span class="flex-center">Advanced Guides</span></h2><div class="collapseContainer_71eca p-2 rounded-xl"><div style="cursor:pointer;transition:transform 0.2s ease-out;transform:rotate(90deg)"><svg width="1em" height="1em" viewBox="0 0 32 32"><path fill="currentColor" d="M22 16 12 26l-1.4-1.4 8.6-8.6-8.6-8.6L12 6z"></path></svg></div></div></div><div class="transition-all duration-300 ease-in-out" style="overflow:hidden"><div class="rspress-sidebar-group transition-opacity duration-500 ease-in-out" style="opacity:1;margin-left:12px"><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/advanced/testing-env"><div class="menuItemActive_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Testing environment</span></div></a></div><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/advanced/understanding-act"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Understanding <code>act</code> function</span></div></a></div></div></div></section><section class="mt-0.5 block" style="margin-left:0"><div class="flex justify-between items-center menuItem_71eca" style="border-radius:0 var(--rp-radius) var(--rp-radius) 0;cursor:pointer"><h2 class="py-2 px-3 text-sm font-medium flex" style="font-size:14px;padding-left:24px;font-weight:bold"><span class="flex-center">Migration Guides</span></h2><div class="collapseContainer_71eca p-2 rounded-xl"><div style="cursor:pointer;transition:transform 0.2s ease-out;transform:rotate(0deg)"><svg width="1em" height="1em" viewBox="0 0 32 32"><path fill="currentColor" d="M22 16 12 26l-1.4-1.4 8.6-8.6-8.6-8.6L12 6z"></path></svg></div></div></div><div class="transition-all duration-300 ease-in-out" style="overflow:hidden;max-height:0"><div class="rspress-sidebar-group transition-opacity duration-500 ease-in-out" style="opacity:0;margin-left:12px"><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/migration/v12"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Migration to 12.x</span></div></a></div><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/migration/jest-matchers"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Migration to built-in Jest matchers</span></div></a></div><div><section class="mt-0.5 block" style="margin-left:18px"><div class="flex justify-between items-center menuItem_71eca" style="cursor:pointer"><h2 class="py-2 px-3 text-sm font-medium flex"><span class="flex-center">Previous versions</span></h2><div class="collapseContainer_71eca p-2 rounded-xl"><div style="cursor:pointer;transition:transform 0.2s ease-out;transform:rotate(0deg)"><svg width="1em" height="1em" viewBox="0 0 32 32"><path fill="currentColor" d="M22 16 12 26l-1.4-1.4 8.6-8.6-8.6-8.6L12 6z"></path></svg></div></div></div><div class="transition-all duration-300 ease-in-out" style="overflow:hidden;max-height:0"><div class="rspress-sidebar-group transition-opacity duration-500 ease-in-out" style="opacity:0;margin-left:0"><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/migration/previous/v11"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Migration to 11.x</span></div></a></div><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/migration/previous/v9"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Migration to 9.x</span></div></a></div><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/migration/previous/v7"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Migration to 7.x</span></div></a></div><div><a class="link_03735 menuLink_71eca rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/migration/previous/v2"><div class="menuItem_71eca mt-0.5 py-2 px-3 font-medium flex" style="font-size:13px;margin-left:18px;border-radius:0 var(--rp-radius) var(--rp-radius) 0"><span>Migration to 2.x</span></div></a></div></div></div></section></div></div></div></section></nav></div></div></div></aside><div class="content_edeb4 rspress-doc-container flex flex-shrink-0 mx-auto"><div class="w-full flex-1"><div><div class="rspress-doc"><!--$--><h1 id="testing-environment" class="text-3xl mb-10 leading-10 tracking-tight title_3b154">Testing environment<a class="link_3b154 header-anchor" aria-hidden="true" href="#testing-environment">#</a></h1>
<div class="rspress-directive info"><div class="rspress-directive-title">INFO</div><div class="rspress-directive-content">
<p class="my-4 leading-7">This document is intended for a more advanced audience who want to understand the internals of our testing environment better, e.g., to contribute to the codebase. You should be able to write integration or component tests without reading this.</p>
</div></div>
<p class="my-4 leading-7">React Native Testing Library allows you to write integration and component tests for your React Native app or library. While the JSX code used in tests closely resembles your React Native app, things are not as simple as they might appear. This document will describe the key elements of our testing environment and highlight things to be aware of when writing more advanced tests or diagnosing issues.</p>
<h2 id="react-renderers" class="mt-12 mb-6 pt-8 text-2xl tracking-tight border-t-[1px] border-divider-light title_3b154">React renderers<a class="link_3b154 header-anchor" aria-hidden="true" href="#react-renderers">#</a></h2>
<p class="my-4 leading-7">React allows you to write declarative code using JSX, write function or class components, or use hooks like <code>useState</code>. You need to use a renderer to output the results of your components. Every React app uses some renderer:</p>
<ul class="list-disc pl-5 my-4 leading-7">
<li class="[&amp;:not(:first-child)]:mt-2">React Native is a renderer for mobile apps,</li>
<li class="[&amp;:not(:first-child)]:mt-2">React DOM is a renderer for web apps,</li>
<li class="[&amp;:not(:first-child)]:mt-2">There are other more <a target="_blank" rel="noopener noreferrer" href="https://github.com/chentsulin/awesome-react-renderer" class="link_03735 link_3b154 inline-link_3b154 rspress-link">specialized renderers</a> that can e.g., render to console or HTML canvas.</li>
</ul>
<p class="my-4 leading-7">When you run your tests in the React Native Testing Library, somewhat contrary to what the name suggests, they are actually <strong class="font-semibold">not</strong> using React Native renderer. This is because this renderer needs to be run on an iOS or Android operating system, so it would need to run on a device or simulator.</p>
<h2 id="react-test-renderer" class="mt-12 mb-6 pt-8 text-2xl tracking-tight border-t-[1px] border-divider-light title_3b154">React Test Renderer<a class="link_3b154 header-anchor" aria-hidden="true" href="#react-test-renderer">#</a></h2>
<p class="my-4 leading-7">Instead, RNTL uses React Test Renderer, a specialized renderer that allows rendering to pure JavaScript objects without access to mobile OS and can run in a Node.js environment using Jest (or any other JavaScript test runner).</p>
<p class="my-4 leading-7">Using React Test Renderer has pros and cons.</p>
<p class="my-4 leading-7">Benefits:</p>
<ul class="list-disc pl-5 my-4 leading-7">
<li class="[&amp;:not(:first-child)]:mt-2">tests can run on most CIs (Linux, etc) and do not require a mobile device or emulator</li>
<li class="[&amp;:not(:first-child)]:mt-2">faster test execution</li>
<li class="[&amp;:not(:first-child)]:mt-2">light runtime environment</li>
</ul>
<p class="my-4 leading-7">Disadvantages:</p>
<ul class="list-disc pl-5 my-4 leading-7">
<li class="[&amp;:not(:first-child)]:mt-2">Tests do not execute native code</li>
<li class="[&amp;:not(:first-child)]:mt-2">Tests are unaware of the view state that would be managed by native components, e.g., focus, unmanaged text boxes, etc.</li>
<li class="[&amp;:not(:first-child)]:mt-2">Assertions do not operate on native view hierarchy</li>
<li class="[&amp;:not(:first-child)]:mt-2">Runtime behaviors are simulated, sometimes imperfectly</li>
</ul>
<p class="my-4 leading-7">It&#x27;s worth noting that the React Testing Library (web one) works a bit differently. While RTL also runs in Jest, it has access to a simulated browser DOM environment from the <code>jsdom</code> package, which allows it to use a regular React DOM renderer. Unfortunately, there is no similar React Native runtime environment package. This is probably because while the browser environment is well-defined and highly standardized, the React Native environment constantly evolves in sync with the evolution of underlying OS-es. Maintaining such an environment would require duplicating countless React Native behaviors and keeping them in sync as React Native develops.</p>
<h2 id="element-tree" class="mt-12 mb-6 pt-8 text-2xl tracking-tight border-t-[1px] border-divider-light title_3b154">Element tree<a class="link_3b154 header-anchor" aria-hidden="true" href="#element-tree">#</a></h2>
<p class="my-4 leading-7">Calling the <code>render()</code> function creates an element tree. This is done internally by invoking <code>TestRenderer.create()</code> method. The output tree represents your React Native component tree, and each node of that tree is an &quot;instance&quot; of some React component (to be more precise, each node represents a React fiber, and only class components have instances, while function components store the hook state using fibers).</p>
<p class="my-4 leading-7">These tree elements are represented by <code>ReactTestInstance</code> type:</p>
<div class="language-tsx"><div class="rspress-code-content rspress-scrollbar"><div><pre class="code" style="background-color:inherit"><code class="language-tsx" style="white-space:pre"><span style="display:block;padding:0 1.25rem"><span class="token" style="color:var(--code-token-keyword)">interface</span><span> </span><span class="token class-name">ReactTestInstance</span><span> </span><span class="token" style="color:var(--code-token-punctuation)">{</span><span>
</span></span><span style="display:block;padding:0 1.25rem"><span> type</span><span class="token operator">:</span><span> ElementType</span><span class="token" style="color:var(--code-token-punctuation)">;</span><span>
</span></span><span style="display:block;padding:0 1.25rem"><span> props</span><span class="token operator">:</span><span> </span><span class="token" style="color:var(--code-token-punctuation)">{</span><span> </span><span class="token" style="color:var(--code-token-punctuation)">[</span><span>propName</span><span class="token operator">:</span><span> </span><span class="token" style="color:var(--code-token-symbol)">string</span><span class="token" style="color:var(--code-token-punctuation)">]</span><span class="token operator">:</span><span> </span><span class="token" style="color:var(--code-token-symbol)">any</span><span> </span><span class="token" style="color:var(--code-token-punctuation)">}</span><span class="token" style="color:var(--code-token-punctuation)">;</span><span>
</span></span><span style="display:block;padding:0 1.25rem"><span> parent</span><span class="token operator">:</span><span> ReactTestInstance </span><span class="token operator">|</span><span> </span><span class="token" style="color:var(--code-token-keyword)">null</span><span class="token" style="color:var(--code-token-punctuation)">;</span><span>
</span></span><span style="display:block;padding:0 1.25rem"><span> children</span><span class="token operator">:</span><span> </span><span class="token" style="color:var(--code-token-symbol)">Array</span><span class="token operator">&lt;</span><span>ReactTestInstance </span><span class="token operator">|</span><span> </span><span class="token" style="color:var(--code-token-symbol)">string</span><span class="token operator">&gt;</span><span class="token" style="color:var(--code-token-punctuation)">;</span><span>
</span></span><span style="display:block;padding:0 1.25rem">
</span><span style="display:block;padding:0 1.25rem"><span> </span><span class="token" style="color:var(--code-token-comment)">// Other props and methods</span><span>
</span></span><span style="display:block;padding:0 1.25rem"><span></span><span class="token" style="color:var(--code-token-punctuation)">}</span></span></code></pre></div><div class="code-button-group_15153"><button><svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 24 24" class="icon-wrapped_15153"><path fill="#22a041" d="M21 5H3v2h18zM3 19h7v-2H3zm0-6h15c1 0 2 .43 2 2s-1 2-2 2h-2v-2l-4 3 4 3v-2h2c2.95 0 4-1.27 4-4 0-2.72-1-4-4-4H3z"></path></svg><svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 24 24" class="icon-wrap_15153"><path fill="currentColor" d="M16 7H3V5h13v2M3 19h13v-2H3v2m19-7-4-3v2H3v2h15v2l4-3Z"></path></svg></button><button class="code-copy-button_15153"><svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 30 30" class="icon-copy_15153"><path fill="currentColor" d="M28 10v18H10V10h18m0-2H10a2 2 0 0 0-2 2v18a2 2 0 0 0 2 2h18a2 2 0 0 0 2-2V10a2 2 0 0 0-2-2Z"></path><path fill="currentColor" d="M4 18H2V4a2 2 0 0 1 2-2h14v2H4Z"></path></svg><svg width="32" height="32" viewBox="0 0 30 30" class="icon-success_15153"><path fill="#49cd37" d="m13 24-9-9 1.414-1.414L13 21.171 26.586 7.586 28 9 13 24z"></path></svg></button></div></div></div>
<p class="my-4 leading-7">Based on: <a target="_blank" rel="noopener noreferrer" href="https://github.com/DefinitelyTyped/DefinitelyTyped/blob/master/types/react-test-renderer/index.d.ts" class="link_03735 link_3b154 inline-link_3b154 rspress-link">https://github.com/DefinitelyTyped/DefinitelyTyped/blob/master/types/react-test-renderer/index.d.ts</a></p>
<h2 id="host-and-composite-components" class="mt-12 mb-6 pt-8 text-2xl tracking-tight border-t-[1px] border-divider-light title_3b154">Host and composite components<a class="link_3b154 header-anchor" aria-hidden="true" href="#host-and-composite-components">#</a></h2>
<p class="my-4 leading-7">One of the most important aspects of the element tree is that it is composed of both host and composite components:</p>
<ul class="list-disc pl-5 my-4 leading-7">
<li class="[&amp;:not(:first-child)]:mt-2"><a target="_blank" rel="noopener noreferrer" href="https://reactnative.dev/architecture/glossary#react-host-components-or-host-components" class="link_03735 link_3b154 inline-link_3b154 rspress-link">Host components</a> will have direct counterparts in the native view tree. Typical examples are <code>&lt;View&gt;</code>, <code>&lt;Text&gt;</code> , <code>&lt;TextInput&gt;</code>, and <code>&lt;Image&gt;</code> from React Native. You can think of these as an analog of <code>&lt;div&gt;</code>, <code>&lt;span&gt;</code> etc on the Web. You can also create custom host views as native modules or import them from 3rd party libraries, like React Navigation or React Native Gesture Handler.</li>
<li class="[&amp;:not(:first-child)]:mt-2"><a target="_blank" rel="noopener noreferrer" href="https://reactnative.dev/architecture/glossary#react-composite-components" class="link_03735 link_3b154 inline-link_3b154 rspress-link">Composite components</a> are React code organization units that exist only on the JavaScript side of your app. Typical examples are components you create (function and class components), components imported from React Native (<code>View</code>, <code>Text</code>, etc.), or 3rd party packages.</li>
</ul>
<p class="my-4 leading-7">That might initially sound confusing since we put React Native&#x27;s <code>View</code> in both categories. There are two <code>View</code> components: composite and host. The relation between them is as follows:</p>
<ul class="list-disc pl-5 my-4 leading-7">
<li class="[&amp;:not(:first-child)]:mt-2">composite <code>View</code> is the type imported from the <code>react-native</code> package. It is a JavaScript component that renders the host <code>View</code> as its only child in the element tree.</li>
<li class="[&amp;:not(:first-child)]:mt-2">host <code>View</code>, which you do not render directly. React Native takes the props you pass to the composite <code>View</code>, does some processing on them and passes them to the host <code>View</code>.</li>
</ul>
<p class="my-4 leading-7">The part of the tree looks as follows:</p>
<div class="language-jsx"><div class="rspress-code-content rspress-scrollbar"><div><pre class="code" style="background-color:inherit"><code class="language-jsx" style="white-space:pre"><span style="display:block;padding:0 1.25rem"><span class="token operator">*</span><span> </span><span class="token" style="color:var(--code-token-punctuation)">&lt;</span><span class="token class-name" style="color:var(--code-token-function)">View</span><span class="token" style="color:var(--code-token-punctuation)">&gt;</span><span class="token plain-text"> (composite)
</span></span><span style="display:block;padding:0 1.25rem"><span class="token plain-text"> * </span><span class="token" style="color:var(--code-token-punctuation)">&lt;</span><span class="token class-name" style="color:var(--code-token-function)">View</span><span class="token" style="color:var(--code-token-punctuation)">&gt;</span><span class="token plain-text"> (host)
</span></span><span style="display:block;padding:0 1.25rem" class="token plain-text"> * children prop passed in JSX</span></code></pre></div><div class="code-button-group_15153"><button><svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 24 24" class="icon-wrapped_15153"><path fill="#22a041" d="M21 5H3v2h18zM3 19h7v-2H3zm0-6h15c1 0 2 .43 2 2s-1 2-2 2h-2v-2l-4 3 4 3v-2h2c2.95 0 4-1.27 4-4 0-2.72-1-4-4-4H3z"></path></svg><svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 24 24" class="icon-wrap_15153"><path fill="currentColor" d="M16 7H3V5h13v2M3 19h13v-2H3v2m19-7-4-3v2H3v2h15v2l4-3Z"></path></svg></button><button class="code-copy-button_15153"><svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 30 30" class="icon-copy_15153"><path fill="currentColor" d="M28 10v18H10V10h18m0-2H10a2 2 0 0 0-2 2v18a2 2 0 0 0 2 2h18a2 2 0 0 0 2-2V10a2 2 0 0 0-2-2Z"></path><path fill="currentColor" d="M4 18H2V4a2 2 0 0 1 2-2h14v2H4Z"></path></svg><svg width="32" height="32" viewBox="0 0 30 30" class="icon-success_15153"><path fill="#49cd37" d="m13 24-9-9 1.414-1.414L13 21.171 26.586 7.586 28 9 13 24z"></path></svg></button></div></div></div>
<p class="my-4 leading-7">A similar relation exists between other composite and host pairs: e.g. <code>Text</code> , <code>TextInput</code>, and <code>Image</code> components:</p>
<div class="language-jsx"><div class="rspress-code-content rspress-scrollbar"><div><pre class="code" style="background-color:inherit"><code class="language-jsx" style="white-space:pre"><span style="display:block;padding:0 1.25rem"><span class="token operator">*</span><span> </span><span class="token" style="color:var(--code-token-punctuation)">&lt;</span><span class="token class-name" style="color:var(--code-token-function)">Text</span><span class="token" style="color:var(--code-token-punctuation)">&gt;</span><span class="token plain-text"> (composite)
</span></span><span style="display:block;padding:0 1.25rem"><span class="token plain-text"> * </span><span class="token" style="color:var(--code-token-punctuation)">&lt;</span><span class="token class-name" style="color:var(--code-token-function)">Text</span><span class="token" style="color:var(--code-token-punctuation)">&gt;</span><span class="token plain-text"> (host)
</span></span><span style="display:block;padding:0 1.25rem" class="token plain-text"> * string (or mixed) content</span></code></pre></div><div class="code-button-group_15153"><button><svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 24 24" class="icon-wrapped_15153"><path fill="#22a041" d="M21 5H3v2h18zM3 19h7v-2H3zm0-6h15c1 0 2 .43 2 2s-1 2-2 2h-2v-2l-4 3 4 3v-2h2c2.95 0 4-1.27 4-4 0-2.72-1-4-4-4H3z"></path></svg><svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 24 24" class="icon-wrap_15153"><path fill="currentColor" d="M16 7H3V5h13v2M3 19h13v-2H3v2m19-7-4-3v2H3v2h15v2l4-3Z"></path></svg></button><button class="code-copy-button_15153"><svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 30 30" class="icon-copy_15153"><path fill="currentColor" d="M28 10v18H10V10h18m0-2H10a2 2 0 0 0-2 2v18a2 2 0 0 0 2 2h18a2 2 0 0 0 2-2V10a2 2 0 0 0-2-2Z"></path><path fill="currentColor" d="M4 18H2V4a2 2 0 0 1 2-2h14v2H4Z"></path></svg><svg width="32" height="32" viewBox="0 0 30 30" class="icon-success_15153"><path fill="#49cd37" d="m13 24-9-9 1.414-1.414L13 21.171 26.586 7.586 28 9 13 24z"></path></svg></button></div></div></div>
<p class="my-4 leading-7">Not all React Native components are organized this way, e.g., when you use <code>Pressable</code> (or <code>TouchableOpacity</code>), there is no host <code>Pressable</code>, but composite <code>Pressable</code> is rendering a host <code>View</code> with specific props being set:</p>
<div class="language-jsx"><div class="rspress-code-content rspress-scrollbar"><div><pre class="code" style="background-color:inherit"><code class="language-jsx" style="white-space:pre"><span style="display:block;padding:0 1.25rem"><span class="token operator">*</span><span> </span><span class="token" style="color:var(--code-token-punctuation)">&lt;</span><span class="token class-name" style="color:var(--code-token-function)">Pressable</span><span class="token" style="color:var(--code-token-punctuation)">&gt;</span><span class="token plain-text"> (composite)
</span></span><span style="display:block;padding:0 1.25rem"><span class="token plain-text"> * </span><span class="token" style="color:var(--code-token-punctuation)">&lt;</span><span class="token class-name" style="color:var(--code-token-function)">View</span><span class="token" style="color:var(--code-token-function)"> </span><span class="token" style="color:var(--code-token-symbol)">accessible</span><span class="token script language-javascript script-punctuation" style="color:var(--code-token-function)">=</span><span class="token script language-javascript" style="color:var(--code-token-punctuation)">{</span><span class="token script language-javascript boolean" style="color:var(--code-token-function)">true</span><span class="token script language-javascript" style="color:var(--code-token-punctuation)">}</span><span class="token" style="color:var(--code-token-function)"> </span><span class="token spread" style="color:var(--code-token-punctuation)">{</span><span class="token spread operator" style="color:var(--code-token-function)">...</span><span class="token spread" style="color:var(--code-token-punctuation)">}</span><span class="token" style="color:var(--code-token-punctuation)">&gt;</span><span class="token plain-text"> (host)
</span></span><span style="display:block;padding:0 1.25rem" class="token plain-text"> * children prop passed in JSX</span></code></pre></div><div class="code-button-group_15153"><button><svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 24 24" class="icon-wrapped_15153"><path fill="#22a041" d="M21 5H3v2h18zM3 19h7v-2H3zm0-6h15c1 0 2 .43 2 2s-1 2-2 2h-2v-2l-4 3 4 3v-2h2c2.95 0 4-1.27 4-4 0-2.72-1-4-4-4H3z"></path></svg><svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 24 24" class="icon-wrap_15153"><path fill="currentColor" d="M16 7H3V5h13v2M3 19h13v-2H3v2m19-7-4-3v2H3v2h15v2l4-3Z"></path></svg></button><button class="code-copy-button_15153"><svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 30 30" class="icon-copy_15153"><path fill="currentColor" d="M28 10v18H10V10h18m0-2H10a2 2 0 0 0-2 2v18a2 2 0 0 0 2 2h18a2 2 0 0 0 2-2V10a2 2 0 0 0-2-2Z"></path><path fill="currentColor" d="M4 18H2V4a2 2 0 0 1 2-2h14v2H4Z"></path></svg><svg width="32" height="32" viewBox="0 0 30 30" class="icon-success_15153"><path fill="#49cd37" d="m13 24-9-9 1.414-1.414L13 21.171 26.586 7.586 28 9 13 24z"></path></svg></button></div></div></div>
<h3 id="differentiating-between-host-and-composite-elements" class="mt-10 mb-2 leading-7 text-xl title_3b154">Differentiating between host and composite elements<a class="link_3b154 header-anchor" aria-hidden="true" href="#differentiating-between-host-and-composite-elements">#</a></h3>
<p class="my-4 leading-7">Any easy way to differentiate between host and composite elements is the <code>type</code> prop of <code>ReactTestInstance</code>:</p>
<ul class="list-disc pl-5 my-4 leading-7">
<li class="[&amp;:not(:first-child)]:mt-2">for host components, it&#x27;s always a string value representing a component name, e.g., <code>&quot;View&quot;</code></li>
<li class="[&amp;:not(:first-child)]:mt-2">for composite components, it&#x27;s a function or class corresponding to the component</li>
</ul>
<p class="my-4 leading-7">You can use the following code to check if a given element is a host one:</p>
<div class="language-jsx"><div class="rspress-code-content rspress-scrollbar"><div><pre class="code" style="background-color:inherit"><code class="language-jsx" style="white-space:pre"><span style="display:block;padding:0 1.25rem"><span class="token" style="color:var(--code-token-keyword)">function</span><span> </span><span class="token" style="color:var(--code-token-function)">isHostElement</span><span class="token" style="color:var(--code-token-punctuation)">(</span><span>element</span><span class="token operator">:</span><span> ReactTestInstance</span><span class="token" style="color:var(--code-token-punctuation)">)</span><span> </span><span class="token" style="color:var(--code-token-punctuation)">{</span><span>
</span></span><span style="display:block;padding:0 1.25rem"><span> </span><span class="token" style="color:var(--code-token-keyword)">return</span><span> </span><span class="token" style="color:var(--code-token-keyword)">typeof</span><span> element</span><span class="token" style="color:var(--code-token-punctuation)">.</span><span>type </span><span class="token operator">===</span><span> </span><span class="token" style="color:var(--code-token-string)">&#x27;string&#x27;</span><span class="token" style="color:var(--code-token-punctuation)">;</span><span>
</span></span><span style="display:block;padding:0 1.25rem"><span></span><span class="token" style="color:var(--code-token-punctuation)">}</span></span></code></pre></div><div class="code-button-group_15153"><button><svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 24 24" class="icon-wrapped_15153"><path fill="#22a041" d="M21 5H3v2h18zM3 19h7v-2H3zm0-6h15c1 0 2 .43 2 2s-1 2-2 2h-2v-2l-4 3 4 3v-2h2c2.95 0 4-1.27 4-4 0-2.72-1-4-4-4H3z"></path></svg><svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 24 24" class="icon-wrap_15153"><path fill="currentColor" d="M16 7H3V5h13v2M3 19h13v-2H3v2m19-7-4-3v2H3v2h15v2l4-3Z"></path></svg></button><button class="code-copy-button_15153"><svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 30 30" class="icon-copy_15153"><path fill="currentColor" d="M28 10v18H10V10h18m0-2H10a2 2 0 0 0-2 2v18a2 2 0 0 0 2 2h18a2 2 0 0 0 2-2V10a2 2 0 0 0-2-2Z"></path><path fill="currentColor" d="M4 18H2V4a2 2 0 0 1 2-2h14v2H4Z"></path></svg><svg width="32" height="32" viewBox="0 0 30 30" class="icon-success_15153"><path fill="#49cd37" d="m13 24-9-9 1.414-1.414L13 21.171 26.586 7.586 28 9 13 24z"></path></svg></button></div></div></div>
<h2 id="tree-nodes" class="mt-12 mb-6 pt-8 text-2xl tracking-tight border-t-[1px] border-divider-light title_3b154">Tree nodes<a class="link_3b154 header-anchor" aria-hidden="true" href="#tree-nodes">#</a></h2>
<p class="my-4 leading-7">We encourage you to only assert values on host views in your tests because they represent the user interface view and controls which the user can see and interact with. Users cannot see or interact with composite views as they exist purely in the JavaScript domain and do not generate any visible UI.</p>
<h3 id="asserting-props" class="mt-10 mb-2 leading-7 text-xl title_3b154">Asserting props<a class="link_3b154 header-anchor" aria-hidden="true" href="#asserting-props">#</a></h3>
<p class="my-4 leading-7">For example, suppose you assert a <code>style</code> prop of a composite element. In that case, there is no guarantee that the style will be visible to the user, as the component author can forget to pass this prop to some underlying <code>View</code> or other host component. Similarly <code>onPress</code> event handler on a composite prop can be unreachable by the user.</p>
<div class="language-jsx"><div class="rspress-code-content rspress-scrollbar"><div><pre class="code" style="background-color:inherit"><code class="language-jsx" style="white-space:pre"><span style="display:block;padding:0 1.25rem"><span class="token" style="color:var(--code-token-keyword)">function</span><span> </span><span class="token" style="color:var(--code-token-function)">ForgotToPassPropsButton</span><span class="token" style="color:var(--code-token-punctuation)">(</span><span class="token" style="color:var(--code-token-punctuation)">{</span><span> title</span><span class="token" style="color:var(--code-token-punctuation)">,</span><span> onPress</span><span class="token" style="color:var(--code-token-punctuation)">,</span><span> style </span><span class="token" style="color:var(--code-token-punctuation)">}</span><span class="token" style="color:var(--code-token-punctuation)">)</span><span> </span><span class="token" style="color:var(--code-token-punctuation)">{</span><span>
</span></span><span style="display:block;padding:0 1.25rem"><span> </span><span class="token" style="color:var(--code-token-keyword)">return</span><span> </span><span class="token" style="color:var(--code-token-punctuation)">(</span><span>
</span></span><span style="display:block;padding:0 1.25rem"><span> </span><span class="token" style="color:var(--code-token-punctuation)">&lt;</span><span class="token class-name" style="color:var(--code-token-function)">Pressable</span><span class="token" style="color:var(--code-token-punctuation)">&gt;</span><span class="token plain-text">
</span></span><span style="display:block;padding:0 1.25rem"><span class="token plain-text"> </span><span class="token" style="color:var(--code-token-punctuation)">&lt;</span><span class="token class-name" style="color:var(--code-token-function)">Text</span><span class="token" style="color:var(--code-token-punctuation)">&gt;</span><span class="token" style="color:var(--code-token-punctuation)">{</span><span>title</span><span class="token" style="color:var(--code-token-punctuation)">}</span><span class="token" style="color:var(--code-token-punctuation)">&lt;/</span><span class="token class-name" style="color:var(--code-token-function)">Text</span><span class="token" style="color:var(--code-token-punctuation)">&gt;</span><span class="token plain-text">
</span></span><span style="display:block;padding:0 1.25rem"><span class="token plain-text"> </span><span class="token" style="color:var(--code-token-punctuation)">&lt;/</span><span class="token class-name" style="color:var(--code-token-function)">Pressable</span><span class="token" style="color:var(--code-token-punctuation)">&gt;</span><span>
</span></span><span style="display:block;padding:0 1.25rem"><span> </span><span class="token" style="color:var(--code-token-punctuation)">)</span><span class="token" style="color:var(--code-token-punctuation)">;</span><span>
</span></span><span style="display:block;padding:0 1.25rem"><span></span><span class="token" style="color:var(--code-token-punctuation)">}</span></span></code></pre></div><div class="code-button-group_15153"><button><svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 24 24" class="icon-wrapped_15153"><path fill="#22a041" d="M21 5H3v2h18zM3 19h7v-2H3zm0-6h15c1 0 2 .43 2 2s-1 2-2 2h-2v-2l-4 3 4 3v-2h2c2.95 0 4-1.27 4-4 0-2.72-1-4-4-4H3z"></path></svg><svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 24 24" class="icon-wrap_15153"><path fill="currentColor" d="M16 7H3V5h13v2M3 19h13v-2H3v2m19-7-4-3v2H3v2h15v2l4-3Z"></path></svg></button><button class="code-copy-button_15153"><svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 30 30" class="icon-copy_15153"><path fill="currentColor" d="M28 10v18H10V10h18m0-2H10a2 2 0 0 0-2 2v18a2 2 0 0 0 2 2h18a2 2 0 0 0 2-2V10a2 2 0 0 0-2-2Z"></path><path fill="currentColor" d="M4 18H2V4a2 2 0 0 1 2-2h14v2H4Z"></path></svg><svg width="32" height="32" viewBox="0 0 30 30" class="icon-success_15153"><path fill="#49cd37" d="m13 24-9-9 1.414-1.414L13 21.171 26.586 7.586 28 9 13 24z"></path></svg></button></div></div></div>
<p class="my-4 leading-7">In the above example, user-defined components accept both <code>onPress</code> and <code>style</code> props but do not pass them (through <code>Pressable</code>) to host views, so they will not affect the user interface. Additionally, React Native and other libraries might pass some of the props under different names or transform their values between composite and host components.</p>
<h2 id="tree-navigation" class="mt-12 mb-6 pt-8 text-2xl tracking-tight border-t-[1px] border-divider-light title_3b154">Tree navigation<a class="link_3b154 header-anchor" aria-hidden="true" href="#tree-navigation">#</a></h2>
<div class="rspress-directive caution"><div class="rspress-directive-title">CAUTION</div><div class="rspress-directive-content"><p class="my-4 leading-7">You should avoid navigating over the element tree, as this makes your testing code fragile and may result in false positives. This section is more relevant for people who want to contribute to our codebase.</p></div></div>
<p class="my-4 leading-7">You will encounter host and composite elements when navigating a tree of react elements using <code>parent</code> or <code>children</code> props of a <code>ReactTestInstance</code> element. You should be careful when navigating the element tree, as the tree structure for third-party components can change independently from your code and cause unexpected test failures.</p>
<p class="my-4 leading-7">Inside RNTL, we have various tree navigation helpers: <code>getHostParent</code>, <code>getHostChildren</code>, etc. These are intentionally not exported, as using them is not recommended.</p>
<h2 id="queries" class="mt-12 mb-6 pt-8 text-2xl tracking-tight border-t-[1px] border-divider-light title_3b154">Queries<a class="link_3b154 header-anchor" aria-hidden="true" href="#queries">#</a></h2>
<p class="my-4 leading-7">All recommended Testing Library queries return host components to encourage the best practices described above.</p>
<p class="my-4 leading-7">Only <code>UNSAFE_*ByType</code> and <code>UNSAFE_*ByProps</code> queries can return both host and composite components depending on used predicates. They are marked as unsafe precisely because testing composite components makes your test more fragile.</p><!--/$--></div><div class="rspress-doc-footer"><footer class="mt-8"><div class="xs:flex pb-5 px-2 justify-end items-center"></div><div class="flex flex-col"></div><div class="flex flex-col sm:flex-row sm:justify-around gap-4 pt-6"><div class="prev_e7091 flex flex-col"><a class="link_03735 pager-link_9b9a7 rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/guides/community-resources"><span class="desc_9b9a7">Previous Page</span><span class="title_9b9a7">Community resources</span></a></div><div class="next_e7091 flex flex-col"><a class="link_03735 pager-link_9b9a7 next_9b9a7 rspress-link cursor-pointer" target="" href="/react-native-testing-library/docs/advanced/understanding-act"><span class="desc_9b9a7">Next page</span><span class="title_9b9a7">Understanding `act` function</span></a></div></div></footer></div></div></div><div class="aside-container_edeb4"><div><div class="flex flex-col"><div class="&lt;lg:hidden"><div id="aside-container" class="relative text-sm font-medium"><div class="leading-7 block text-sm font-semibold pl-3">Contents</div><nav class="mt-1"><ul class="relative"><li><a href="#react-renderers" title="React renderers" class="aside-link transition-all duration-300 hover:text-text-1 text-text-2 block" style="padding-left:0;font-weight:semibold"><span class="aside-link-text block">React renderers</span></a></li><li><a href="#react-test-renderer" title="React Test Renderer" class="aside-link transition-all duration-300 hover:text-text-1 text-text-2 block" style="padding-left:0;font-weight:semibold"><span class="aside-link-text block">React Test Renderer</span></a></li><li><a href="#element-tree" title="Element tree" class="aside-link transition-all duration-300 hover:text-text-1 text-text-2 block" style="padding-left:0;font-weight:semibold"><span class="aside-link-text block">Element tree</span></a></li><li><a href="#host-and-composite-components" title="Host and composite components" class="aside-link transition-all duration-300 hover:text-text-1 text-text-2 block" style="padding-left:0;font-weight:semibold"><span class="aside-link-text block">Host and composite components</span></a></li><li><a href="#differentiating-between-host-and-composite-elements" title="Differentiating between host and composite elements" class="aside-link transition-all duration-300 hover:text-text-1 text-text-2 block" style="padding-left:12px;font-weight:semibold"><span class="aside-link-text block">Differentiating between host and composite elements</span></a></li><li><a href="#tree-nodes" title="Tree nodes" class="aside-link transition-all duration-300 hover:text-text-1 text-text-2 block" style="padding-left:0;font-weight:semibold"><span class="aside-link-text block">Tree nodes</span></a></li><li><a href="#asserting-props" title="Asserting props" class="aside-link transition-all duration-300 hover:text-text-1 text-text-2 block" style="padding-left:12px;font-weight:semibold"><span class="aside-link-text block">Asserting props</span></a></li><li><a href="#tree-navigation" title="Tree navigation" class="aside-link transition-all duration-300 hover:text-text-1 text-text-2 block" style="padding-left:0;font-weight:semibold"><span class="aside-link-text block">Tree navigation</span></a></li><li><a href="#queries" title="Queries" class="aside-link transition-all duration-300 hover:text-text-1 text-text-2 block" style="padding-left:0;font-weight:semibold"><span class="aside-link-text block">Queries</span></a></li></ul></nav></div></div></div></div></div></div></div></section></div></div><div id="search-container"></div></body></html>
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