<h2 dir="auto">Bug Report</h2>

<ul class="contains-task-list">
<li class="task-list-item"><input type="checkbox" id="" disabled="" class="task-list-item-checkbox"> I would like to work on a fix!</li>
</ul>

<p dir="auto"><strong>Current Behavior</strong><br>
A clear and concise description of the behavior.<br>
test fails because of syntaxError<br>
FAIL  <strong>tests</strong>/App.test.js<br>
● Test suite failed to run</p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="SyntaxError: /Users/Jostein/Documents/jobb_Ovitas/projects/hunnor/node_modules/react-native/jest/mockComponent.js: Support for the experimental syntax 'classProperties' i"><pre class="notranslate"><code class="notranslate">SyntaxError: /Users/Jostein/Documents/jobb_Ovitas/projects/hunnor/node_modules/react-native/jest/mockComponent.js: Support for the experimental syntax 'classProperties' i
</code></pre></div>
<p dir="auto">sn't currently enabled (20:24):</p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="  18 | 
  19 |   const Component = class extends SuperClass {
&gt; 20 |     static displayName = 'Component';
     |                        ^
  21 | 
  22 |     render() {
  23 |       const name =

Add @babel/plugin-proposal-class-properties (https://git.io/vb4SL) to the 'plugins' section of your Babel config to enable transformation."><pre class="notranslate"><code class="notranslate">  18 | 
  19 |   const Component = class extends SuperClass {
&gt; 20 |     static displayName = 'Component';
     |                        ^
  21 | 
  22 |     render() {
  23 |       const name =

Add @babel/plugin-proposal-class-properties (https://git.io/vb4SL) to the 'plugins' section of your Babel config to enable transformation.
</code></pre></div>
<p dir="auto"><strong>Input Code</strong></p>
<ul dir="auto">
<li>REPL or Repo link if applicable:<br>
Jest configuration in package.json</li>
</ul>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content=" &quot;jest&quot;: {
    &quot;preset&quot;: &quot;jest-expo&quot;,
    &quot;verbose&quot;: true,
    &quot;transformIgnorePatterns&quot;: [
      &quot;node_modules/(?!(react-native|my-project|react-native-button)/)&quot;
    ],
    &quot;setupFiles&quot;: [
      &quot;./setupTests.js&quot;
    ],
    &quot;collectCoverage&quot;: true,
    &quot;coverageReporters&quot;: [
      &quot;json&quot;,
      &quot;html&quot;
    ]
  },"><pre class="notranslate"><code class="notranslate"> "jest": {
    "preset": "jest-expo",
    "verbose": true,
    "transformIgnorePatterns": [
      "node_modules/(?!(react-native|my-project|react-native-button)/)"
    ],
    "setupFiles": [
      "./setupTests.js"
    ],
    "collectCoverage": true,
    "coverageReporters": [
      "json",
      "html"
    ]
  },
</code></pre></div>
<p dir="auto"><strong>Expected behavior/code</strong><br>
A clear and concise description of what you expected to happen (or code).<br>
expect jest to run test</p>
<p dir="auto"><strong>Babel Configuration (babel.config.js, .babelrc, package.json#babel, cli command, .eslintrc)</strong></p>
<ul dir="auto">
<li>Filename: <code class="notranslate">.babelrc</code></li>
</ul>
<div class="highlight highlight-source-js notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="{
  &quot;presets&quot;: [&quot;module:metro-react-native-babel-preset&quot;, &quot;babel-preset-expo&quot;],
  &quot;sourceMaps&quot;:true,
  &quot;plugins&quot;: [&quot;@babel/plugin-proposal-class-properties&quot;]

}"><pre class="notranslate"><span class="pl-kos">{</span>
  <span class="pl-s">"presets"</span>: <span class="pl-kos">[</span><span class="pl-s">"module:metro-react-native-babel-preset"</span><span class="pl-kos">,</span> <span class="pl-s">"babel-preset-expo"</span><span class="pl-kos">]</span><span class="pl-kos">,</span>
  <span class="pl-s">"sourceMaps"</span>:<span class="pl-c1">true</span><span class="pl-kos">,</span>
  <span class="pl-s">"plugins"</span>: <span class="pl-kos">[</span><span class="pl-s">"@babel/plugin-proposal-class-properties"</span><span class="pl-kos">]</span>

<span class="pl-kos">}</span></pre></div>
<p dir="auto"><strong>Environment</strong></p>

<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="System:
    OS: macOS 10.15.2
  Binaries:
    Node: 13.6.0 - ~/Documents/jobb_Ovitas/projects/hunnor/node_modules/.bin/node
    Yarn: 1.19.2 - /usr/local/bin/yarn
    npm: 6.13.6 - /usr/local/bin/npm
  npmPackages:
    @babel/core: ^7.8.3 =&gt; 7.8.3 
    @babel/plugin-proposal-class-properties: ^7.8.3 =&gt; 7.8.3 
    @babel/polyfill: ^7.8.3 =&gt; 7.8.3 
    @babel/preset-env: ^7.8.3 =&gt; 7.8.3 
    babel-core: ^7.0.0-bridge.0 =&gt; 7.0.0-bridge.0 
    babel-eslint: ^10.0.2 =&gt; 10.0.3 
    babel-jest: ^23.6.0 =&gt; 23.6.0 
    eslint: ^6.0.1 =&gt; 6.8.0 
    jest: ^24.9.0 =&gt; 24.9.0 
    react-native: https://github.com/expo/react-native/archive/sdk-36.0.0.tar.gz =&gt; 0.61.4 "><pre class="notranslate"><code class="notranslate">System:
    OS: macOS 10.15.2
  Binaries:
    Node: 13.6.0 - ~/Documents/jobb_Ovitas/projects/hunnor/node_modules/.bin/node
    Yarn: 1.19.2 - /usr/local/bin/yarn
    npm: 6.13.6 - /usr/local/bin/npm
  npmPackages:
    @babel/core: ^7.8.3 =&gt; 7.8.3 
    @babel/plugin-proposal-class-properties: ^7.8.3 =&gt; 7.8.3 
    @babel/polyfill: ^7.8.3 =&gt; 7.8.3 
    @babel/preset-env: ^7.8.3 =&gt; 7.8.3 
    babel-core: ^7.0.0-bridge.0 =&gt; 7.0.0-bridge.0 
    babel-eslint: ^10.0.2 =&gt; 10.0.3 
    babel-jest: ^23.6.0 =&gt; 23.6.0 
    eslint: ^6.0.1 =&gt; 6.8.0 
    jest: ^24.9.0 =&gt; 24.9.0 
    react-native: https://github.com/expo/react-native/archive/sdk-36.0.0.tar.gz =&gt; 0.61.4 
</code></pre></div>
<ul dir="auto">
<li>Babel version(s): [e.g. v6.0.0, v7.0.0-beta.34]</li>
<li>Node/npm version: [e.g. Node 8/npm 5]</li>
<li>OS: [e.g. OSX 10.13.4, Windows 10]</li>
<li>Monorepo: [e.g. yes/no/Lerna]</li>
<li>How you are using Babel: [e.g. <code class="notranslate">cli</code>, <code class="notranslate">register</code>, <code class="notranslate">loader</code>]</li>
</ul>
<p dir="auto"><strong>Possible Solution</strong></p>

<p dir="auto"><strong>Additional context/Screenshots</strong><br>
Add any other context about the problem here. If applicable, add screenshots to help explain.</p>
<h2 dir="auto">Bug Report</h2>
<p dir="auto"><strong>Current Behavior</strong></p>
<p dir="auto">There are duplicated calls to the <code class="notranslate">assertThisInitialized</code> helper.</p>
<div class="highlight highlight-source-js notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="let Foo =
/*#__PURE__*/
function (_Bar) {
  _inheritsLoose(Foo, _Bar);

  function Foo() {
    var _this;

    _this = _Bar.call(this) || this;
    something(_assertThisInitialized(_assertThisInitialized(_this)));
    return _this;
  }

  return Foo;
}(Bar);"><pre class="notranslate"><span class="pl-k">let</span> <span class="pl-v">Foo</span> <span class="pl-c1">=</span>
<span class="pl-c">/*#__PURE__*/</span>
<span class="pl-k">function</span> <span class="pl-kos">(</span><span class="pl-s1">_Bar</span><span class="pl-kos">)</span> <span class="pl-kos">{</span>
  <span class="pl-en">_inheritsLoose</span><span class="pl-kos">(</span><span class="pl-v">Foo</span><span class="pl-kos">,</span> <span class="pl-s1">_Bar</span><span class="pl-kos">)</span><span class="pl-kos">;</span>

  <span class="pl-k">function</span> <span class="pl-v">Foo</span><span class="pl-kos">(</span><span class="pl-kos">)</span> <span class="pl-kos">{</span>
    <span class="pl-k">var</span> <span class="pl-s1">_this</span><span class="pl-kos">;</span>

    <span class="pl-s1">_this</span> <span class="pl-c1">=</span> <span class="pl-s1">_Bar</span><span class="pl-kos">.</span><span class="pl-en">call</span><span class="pl-kos">(</span><span class="pl-smi">this</span><span class="pl-kos">)</span> <span class="pl-c1">||</span> <span class="pl-smi">this</span><span class="pl-kos">;</span>
    <span class="pl-en">something</span><span class="pl-kos">(</span><span class="pl-en">_assertThisInitialized</span><span class="pl-kos">(</span><span class="pl-en">_assertThisInitialized</span><span class="pl-kos">(</span><span class="pl-s1">_this</span><span class="pl-kos">)</span><span class="pl-kos">)</span><span class="pl-kos">)</span><span class="pl-kos">;</span>
    <span class="pl-k">return</span> <span class="pl-s1">_this</span><span class="pl-kos">;</span>
  <span class="pl-kos">}</span>

  <span class="pl-k">return</span> <span class="pl-v">Foo</span><span class="pl-kos">;</span>
<span class="pl-kos">}</span><span class="pl-kos">(</span><span class="pl-v">Bar</span><span class="pl-kos">)</span><span class="pl-kos">;</span></pre></div>
<p dir="auto"><strong>Input Code</strong></p>
<div class="highlight highlight-source-js notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="class Foo extends Bar {
  constructor() {
    super();
    something(this);
  }
}"><pre class="notranslate"><span class="pl-k">class</span> <span class="pl-v">Foo</span> <span class="pl-k">extends</span> <span class="pl-v">Bar</span> <span class="pl-kos">{</span>
  <span class="pl-en">constructor</span><span class="pl-kos">(</span><span class="pl-kos">)</span> <span class="pl-kos">{</span>
    <span class="pl-smi">super</span><span class="pl-kos">(</span><span class="pl-kos">)</span><span class="pl-kos">;</span>
    <span class="pl-en">something</span><span class="pl-kos">(</span><span class="pl-smi">this</span><span class="pl-kos">)</span><span class="pl-kos">;</span>
  <span class="pl-kos">}</span>
<span class="pl-kos">}</span></pre></div>
<p dir="auto"><strong>Expected behavior/code</strong></p>
<div class="highlight highlight-source-js notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="let Foo =
/*#__PURE__*/
function (_Bar) {
  _inheritsLoose(Foo, _Bar);

  function Foo() {
    var _this;

    _this = _Bar.call(this) || this;
    something(_assertThisInitialized(_this));
    return _this;
  }

  return Foo;
}(Bar);"><pre class="notranslate"><span class="pl-k">let</span> <span class="pl-v">Foo</span> <span class="pl-c1">=</span>
<span class="pl-c">/*#__PURE__*/</span>
<span class="pl-k">function</span> <span class="pl-kos">(</span><span class="pl-s1">_Bar</span><span class="pl-kos">)</span> <span class="pl-kos">{</span>
  <span class="pl-en">_inheritsLoose</span><span class="pl-kos">(</span><span class="pl-v">Foo</span><span class="pl-kos">,</span> <span class="pl-s1">_Bar</span><span class="pl-kos">)</span><span class="pl-kos">;</span>

  <span class="pl-k">function</span> <span class="pl-v">Foo</span><span class="pl-kos">(</span><span class="pl-kos">)</span> <span class="pl-kos">{</span>
    <span class="pl-k">var</span> <span class="pl-s1">_this</span><span class="pl-kos">;</span>

    <span class="pl-s1">_this</span> <span class="pl-c1">=</span> <span class="pl-s1">_Bar</span><span class="pl-kos">.</span><span class="pl-en">call</span><span class="pl-kos">(</span><span class="pl-smi">this</span><span class="pl-kos">)</span> <span class="pl-c1">||</span> <span class="pl-smi">this</span><span class="pl-kos">;</span>
    <span class="pl-en">something</span><span class="pl-kos">(</span><span class="pl-en">_assertThisInitialized</span><span class="pl-kos">(</span><span class="pl-s1">_this</span><span class="pl-kos">)</span><span class="pl-kos">)</span><span class="pl-kos">;</span>
    <span class="pl-k">return</span> <span class="pl-s1">_this</span><span class="pl-kos">;</span>
  <span class="pl-kos">}</span>

  <span class="pl-k">return</span> <span class="pl-v">Foo</span><span class="pl-kos">;</span>
<span class="pl-kos">}</span><span class="pl-kos">(</span><span class="pl-v">Bar</span><span class="pl-kos">)</span><span class="pl-kos">;</span></pre></div>
<p dir="auto"><strong>Environment</strong></p>
<ul dir="auto">
<li>Babel version(s): v7.0.0-beta.48</li>
<li>Node/npm version: Node 8</li>
<li>OS: OS X</li>
<li>Monorepo: no</li>
<li>How you are using Babel: core</li>
</ul>