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Andrew Clark
6334614860
The www builds include disableLegacyContext as a dynamic flag, so we should be running the tests in that mode, too. Previously we were overriding the flag during the test run. This strategy usually doesn't work because the flags get compiled out in the final build, but we happen to not test www in build mode, only source. To get of this hacky override, I added a test gate to every test that uses legacy context. When we eventually remove legacy context from the codebase, this should make it slightly easier to find which tests are affected. And removes one more hack from our hack-ridden test config. Given that sometimes www has features enabled that aren't on in other builds, we might want to consider testing its build artifacts in CI, rather than just source. That would have forced this cleanup to happen sooner. Currently we only test the public builds in CI.
react
React is a JavaScript library for creating user interfaces.
The react package contains only the functionality necessary to define React components. It is typically used together with a React renderer like react-dom for the web, or react-native for the native environments.
Note: by default, React will be in development mode. The development version includes extra warnings about common mistakes, whereas the production version includes extra performance optimizations and strips all error messages. Don't forget to use the production build when deploying your application.
Usage
import { useState } from 'react';
import { createRoot } from 'react-dom/client';
function Counter() {
const [count, setCount] = useState(0);
return (
<>
<h1>{count}</h1>
<button onClick={() => setCount(count + 1)}>
Increment
</button>
</>
);
}
const root = createRoot(document.getElementById('root'));
root.render(<Counter />);