'use strict';
let React;
let ReactDOMServer;
let PropTypes;
let ReactSharedInternals;
let assertConsoleErrorDev;
describe('ReactDOMServer', () => {
beforeEach(() => {
jest.resetModules();
React = require('react');
PropTypes = require('prop-types');
ReactDOMServer = require('react-dom/server');
assertConsoleErrorDev =
require('internal-test-utils').assertConsoleErrorDev;
ReactSharedInternals =
React.__CLIENT_INTERNALS_DO_NOT_USE_OR_WARN_USERS_THEY_CANNOT_UPGRADE;
});
describe('renderToString', () => {
it('should generate simple markup', () => {
const response = ReactDOMServer.renderToString(<span>hello world</span>);
expect(response).toMatch(new RegExp('<span' + '>hello world</span>'));
});
it('should generate simple markup for self-closing tags', () => {
const response = ReactDOMServer.renderToString(<img />);
expect(response).toMatch(new RegExp('<img' + '/>'));
});
it('should generate comment markup for component returns null', () => {
class NullComponent extends React.Component {
render() {
return null;
}
}
const response = ReactDOMServer.renderToString(<NullComponent />);
expect(response).toBe('');
});
it('should render composite components', () => {
class Parent extends React.Component {
render() {
return (
<div>
<Child name="child" />
</div>
);
}
}
class Child extends React.Component {
render() {
return <span>My name is {this.props.name}</span>;
}
}
const response = ReactDOMServer.renderToString(<Parent />);
expect(response).toMatch(
new RegExp(
'<div>' +
'<span' +
'>' +
'My name is <!-- -->child' +
'</span>' +
'</div>',
),
);
});
it('should only execute certain lifecycle methods', () => {
function runTest() {
const lifecycle = [];
class TestComponent extends React.Component {
constructor(props) {
super(props);
lifecycle.push('getInitialState');
this.state = {name: 'TestComponent'};
}
UNSAFE_componentWillMount() {
lifecycle.push('componentWillMount');
}
componentDidMount() {
lifecycle.push('componentDidMount');
}
render() {
lifecycle.push('render');
return <span>Component name: {this.state.name}</span>;
}
UNSAFE_componentWillUpdate() {
lifecycle.push('componentWillUpdate');
}
componentDidUpdate() {
lifecycle.push('componentDidUpdate');
}
shouldComponentUpdate() {
lifecycle.push('shouldComponentUpdate');
}
UNSAFE_componentWillReceiveProps() {
lifecycle.push('componentWillReceiveProps');
}
componentWillUnmount() {
lifecycle.push('componentWillUnmount');
}
}
const response = ReactDOMServer.renderToString(<TestComponent />);
expect(response).toMatch(
new RegExp(
'<span>' + 'Component name: <!-- -->TestComponent' + '</span>',
),
);
expect(lifecycle).toEqual([
'getInitialState',
'componentWillMount',
'render',
]);
}
runTest();
});
it('should throw with silly args', () => {
expect(
ReactDOMServer.renderToString.bind(ReactDOMServer, {x: 123}),
).toThrowError(
'Objects are not valid as a React child (found: object with keys {x})',
);
});
it('should throw prop mapping error for an <iframe /> with invalid props', () => {
expect(() => {
ReactDOMServer.renderToString(<iframe style="border:none;" />);
}).toThrowError(
'The `style` prop expects a mapping from style properties to values, not ' +
"a string. For example, style={{marginRight: spacing + 'em'}} when using JSX.",
);
});
it('should not crash on poisoned hasOwnProperty', () => {
const html = ReactDOMServer.renderToString(
<div hasOwnProperty="poison">
<span unknown="test" />
</div>,
);
assertConsoleErrorDev([
'React does not recognize the `hasOwnProperty` prop on a DOM element. ' +
'If you intentionally want it to appear in the DOM as a custom attribute, ' +
'spell it as lowercase `hasownproperty` instead. ' +
'If you accidentally passed it from a parent component, remove it from the DOM element.\n' +
' in div (at **)',
]);
expect(html).toContain('<span unknown="test">');
});
});
describe('renderToStaticMarkup', () => {
it('should not put checksum and React ID on components', () => {
class NestedComponent extends React.Component {
render() {
return <div>inner text</div>;
}
}
class TestComponent extends React.Component {
render() {
return (
<span>
<NestedComponent />
</span>
);
}
}
const response = ReactDOMServer.renderToStaticMarkup(<TestComponent />);
expect(response).toBe('<span><div>inner text</div></span>');
});
it('should not put checksum and React ID on text components', () => {
class TestComponent extends React.Component {
render() {
return (
<span>
{'hello'} {'world'}
</span>
);
}
}
const response = ReactDOMServer.renderToStaticMarkup(<TestComponent />);
expect(response).toBe('<span>hello world</span>');
});
it('should not use comments for empty nodes', () => {
class TestComponent extends React.Component {
render() {
return null;
}
}
const response = ReactDOMServer.renderToStaticMarkup(<TestComponent />);
expect(response).toBe('');
});
it('should only execute certain lifecycle methods', () => {
function runTest() {
const lifecycle = [];
class TestComponent extends React.Component {
constructor(props) {
super(props);
lifecycle.push('getInitialState');
this.state = {name: 'TestComponent'};
}
UNSAFE_componentWillMount() {
lifecycle.push('componentWillMount');
}
componentDidMount() {
lifecycle.push('componentDidMount');
}
render() {
lifecycle.push('render');
return <span>Component name: {this.state.name}</span>;
}
UNSAFE_componentWillUpdate() {
lifecycle.push('componentWillUpdate');
}
componentDidUpdate() {
lifecycle.push('componentDidUpdate');
}
shouldComponentUpdate() {
lifecycle.push('shouldComponentUpdate');
}
UNSAFE_componentWillReceiveProps() {
lifecycle.push('componentWillReceiveProps');
}
componentWillUnmount() {
lifecycle.push('componentWillUnmount');
}
}
const response = ReactDOMServer.renderToStaticMarkup(<TestComponent />);
expect(response).toBe('<span>Component name: TestComponent</span>');
expect(lifecycle).toEqual([
'getInitialState',
'componentWillMount',
'render',
]);
}
runTest();
});
it('should throw with silly args', () => {
expect(
ReactDOMServer.renderToStaticMarkup.bind(ReactDOMServer, {x: 123}),
).toThrowError(
'Objects are not valid as a React child (found: object with keys {x})',
);
});
it('allows setState in componentWillMount without using DOM', () => {
class Component extends React.Component {
UNSAFE_componentWillMount() {
this.setState({text: 'hello, world'});
}
render() {
return <div>{this.state.text}</div>;
}
}
const markup = ReactDOMServer.renderToStaticMarkup(<Component />);
expect(markup).toContain('hello, world');
});
it('allows setState in componentWillMount with custom constructor', () => {
class Component extends React.Component {
constructor() {
super();
this.state = {text: 'default state'};
}
UNSAFE_componentWillMount() {
this.setState({text: 'hello, world'});
}
render() {
return <div>{this.state.text}</div>;
}
}
const markup = ReactDOMServer.renderToStaticMarkup(<Component />);
expect(markup).toContain('hello, world');
});
it('renders with props when using custom constructor', () => {
class Component extends React.Component {
constructor() {
super();
}
render() {
return <div>{this.props.text}</div>;
}
}
const markup = ReactDOMServer.renderToStaticMarkup(
<Component text="hello, world" />,
);
expect(markup).toContain('hello, world');
});
it('renders with context when using custom constructor', () => {
class Component extends React.Component {
constructor() {
super();
}
render() {
return <div>{this.context.text}</div>;
}
}
Component.contextTypes = {
text: PropTypes.string.isRequired,
};
class ContextProvider extends React.Component {
getChildContext() {
return {
text: 'hello, world',
};
}
render() {
return this.props.children;
}
}
ContextProvider.childContextTypes = {
text: PropTypes.string,
};
const markup = ReactDOMServer.renderToStaticMarkup(
<ContextProvider>
<Component />
</ContextProvider>,
);
assertConsoleErrorDev([
'ContextProvider uses the legacy childContextTypes API which will soon be removed. ' +
'Use React.createContext() instead. (https://react.dev/link/legacy-context)\n' +
' in ContextProvider (at **)',
'Component uses the legacy contextTypes API which will soon be removed. ' +
'Use React.createContext() with static contextType instead. (https://react.dev/link/legacy-context)\n' +
' in Component (at **)',
]);
expect(markup).toContain('hello, world');
});
it('renders with new context API', () => {
const Context = React.createContext(0);
function Consumer(props) {
return (
<Context.Consumer>{value => 'Result: ' + value}</Context.Consumer>
);
}
const Indirection = React.Fragment;
function App(props) {
return (
<Context.Provider value={props.value}>
<Context.Provider value={2}>
<Consumer />
</Context.Provider>
<Indirection>
<Indirection>
<Consumer />
<Context.Provider value={3}>
<Consumer />
</Context.Provider>
</Indirection>
</Indirection>
<Consumer />
</Context.Provider>
);
}
const markup = ReactDOMServer.renderToStaticMarkup(<App value={1} />);
const results = markup.match(/\d+/g).map(Number);
expect(results).toEqual([2, 1, 3, 1]);
});
it('renders with dispatcher.readContext mechanism', () => {
const Context = React.createContext(0);
function readContext(context) {
return ReactSharedInternals.H.readContext(context);
}
function Consumer(props) {
return 'Result: ' + readContext(Context);
}
const Indirection = React.Fragment;
function App(props) {
return (
<Context.Provider value={props.value}>
<Context.Provider value={2}>
<Consumer />
</Context.Provider>
<Indirection>
<Indirection>
<Consumer />
<Context.Provider value={3}>
<Consumer />
</Context.Provider>
</Indirection>
</Indirection>
<Consumer />
</Context.Provider>
);
}
const markup = ReactDOMServer.renderToStaticMarkup(<App value={1} />);
const results = markup.match(/\d+/g).map(Number);
expect(results).toEqual([2, 1, 3, 1]);
});
it('renders context API, reentrancy', () => {
const Context = React.createContext(0);
function Consumer(props) {
return (
<Context.Consumer>{value => 'Result: ' + value}</Context.Consumer>
);
}
let reentrantMarkup;
function Reentrant() {
reentrantMarkup = ReactDOMServer.renderToStaticMarkup(
<App value={1} reentrant={false} />,
);
return null;
}
const Indirection = React.Fragment;
function App(props) {
return (
<Context.Provider value={props.value}>
{props.reentrant && <Reentrant />}
<Context.Provider value={2}>
<Consumer />
</Context.Provider>
<Indirection>
<Indirection>
<Consumer />
<Context.Provider value={3}>
<Consumer />
</Context.Provider>
</Indirection>
</Indirection>
<Consumer />
</Context.Provider>
);
}
const markup = ReactDOMServer.renderToStaticMarkup(
<App value={1} reentrant={true} />,
);
const results = markup.match(/\d+/g).map(Number);
const reentrantResults = reentrantMarkup.match(/\d+/g).map(Number);
expect(results).toEqual([2, 1, 3, 1]);
expect(reentrantResults).toEqual([2, 1, 3, 1]);
});
it('renders components with different batching strategies', () => {
class StaticComponent extends React.Component {
render() {
const staticContent = ReactDOMServer.renderToStaticMarkup(
<div>
<img src="foo-bar.jpg" />
</div>,
);
return <div dangerouslySetInnerHTML={{__html: staticContent}} />;
}
}
class Component extends React.Component {
UNSAFE_componentWillMount() {
this.setState({text: 'hello, world'});
}
render() {
return <div>{this.state.text}</div>;
}
}
expect(
ReactDOMServer.renderToString.bind(
ReactDOMServer,
<div>
<StaticComponent />
<Component />
</div>,
),
).not.toThrow();
});
it('renders synchronously resolved lazy component', () => {
const LazyFoo = React.lazy(() => ({
then(resolve) {
resolve({
default: function Foo({id}) {
return <div id={id}>lazy</div>;
},
});
},
}));
expect(ReactDOMServer.renderToStaticMarkup(<LazyFoo id="foo" />)).toEqual(
'<div id="foo">lazy</div>',
);
});
it('throws error from synchronously rejected lazy component', () => {
const LazyFoo = React.lazy(() => ({
then(resolve, reject) {
reject(new Error('Bad lazy'));
},
}));
expect(() => ReactDOMServer.renderToStaticMarkup(<LazyFoo />)).toThrow(
'Bad lazy',
);
});
it('aborts synchronously any suspended tasks and renders their fallbacks', () => {
const promise = new Promise(res => {});
function Suspender() {
throw promise;
}
const response = ReactDOMServer.renderToStaticMarkup(
<React.Suspense fallback={'fallback'}>
<Suspender />
</React.Suspense>,
);
expect(response).toEqual('fallback');
});
});
it('warns with a no-op when an async setState is triggered', () => {
class Foo extends React.Component {
UNSAFE_componentWillMount() {
this.setState({text: 'hello'});
setTimeout(() => {
this.setState({text: 'error'});
});
}
render() {
return <div onClick={() => {}}>{this.state.text}</div>;
}
}
ReactDOMServer.renderToString(<Foo />);
jest.runOnlyPendingTimers();
assertConsoleErrorDev(
[
'Can only update a mounting component. ' +
'This usually means you called setState() outside componentWillMount() on the server. ' +
'This is a no-op.\n' +
'\n' +
'Please check the code for the Foo component.',
],
{withoutStack: true},
);
const markup = ReactDOMServer.renderToStaticMarkup(<Foo />);
expect(markup).toBe('<div>hello</div>');
jest.runOnlyPendingTimers();
});
it('warns with a no-op when an async forceUpdate is triggered', () => {
class Baz extends React.Component {
UNSAFE_componentWillMount() {
this.forceUpdate();
setTimeout(() => {
this.forceUpdate();
});
}
render() {
return <div onClick={() => {}} />;
}
}
ReactDOMServer.renderToString(<Baz />);
jest.runOnlyPendingTimers();
assertConsoleErrorDev(
[
'Can only update a mounting component. ' +
'This usually means you called forceUpdate() outside componentWillMount() on the server. ' +
'This is a no-op.\n' +
'\n' +
'Please check the code for the Baz component.',
],
{withoutStack: true},
);
const markup = ReactDOMServer.renderToStaticMarkup(<Baz />);
expect(markup).toBe('<div></div>');
});
it('does not get confused by throwing null', () => {
function Bad() {
throw null;
}
let didError;
let error;
try {
ReactDOMServer.renderToString(<Bad />);
} catch (err) {
didError = true;
error = err;
}
expect(didError).toBe(true);
expect(error).toBe(null);
});
it('does not get confused by throwing undefined', () => {
function Bad() {
throw undefined;
}
let didError;
let error;
try {
ReactDOMServer.renderToString(<Bad />);
} catch (err) {
didError = true;
error = err;
}
expect(didError).toBe(true);
expect(error).toBe(undefined);
});
it('does not get confused by throwing a primitive', () => {
function Bad() {
throw 'foo';
}
let didError;
let error;
try {
ReactDOMServer.renderToString(<Bad />);
} catch (err) {
didError = true;
error = err;
}
expect(didError).toBe(true);
expect(error).toBe('foo');
});
it('should throw (in dev) when children are mutated during render', () => {
function Wrapper(props) {
props.children[1] = <p key={1} />;
return <div>{props.children}</div>;
}
if (__DEV__) {
expect(() => {
ReactDOMServer.renderToStaticMarkup(
<Wrapper>
<span key={0} />
<span key={1} />
<span key={2} />
</Wrapper>,
);
}).toThrowError(/Cannot assign to read only property.*/);
} else {
expect(
ReactDOMServer.renderToStaticMarkup(
<Wrapper>
<span key={0} />
<span key={1} />
<span key={2} />
</Wrapper>,
),
).toContain('<p>');
}
});
it('warns about lowercase html but not in svg tags', () => {
function CompositeG(props) {
return <g>{props.children}</g>;
}
ReactDOMServer.renderToStaticMarkup(
<div>
<inPUT />
<svg>
<CompositeG>
<linearGradient />
<foreignObject>
{/* back to HTML */}
<iFrame />
</foreignObject>
</CompositeG>
</svg>
</div>,
);
assertConsoleErrorDev([
'<inPUT /> is using incorrect casing. ' +
'Use PascalCase for React components, ' +
'or lowercase for HTML elements.\n' +
' in inPUT (at **)',
'<iFrame /> is using incorrect casing. ' +
'Use PascalCase for React components, ' +
'or lowercase for HTML elements.\n' +
' in iFrame (at **)',
]);
});
it('should warn about contentEditable and children', () => {
ReactDOMServer.renderToString(<div contentEditable={true} children="" />);
assertConsoleErrorDev([
'A component is `contentEditable` and contains `children` ' +
'managed by React. It is now your responsibility to guarantee that ' +
'none of those nodes are unexpectedly modified or duplicated. This ' +
'is probably not intentional.\n' +
' in div (at **)',
]);
});
it('should warn when server rendering a class with a render method that does not extend React.Component', () => {
class ClassWithRenderNotExtended {
render() {
return <div />;
}
}
expect(() =>
ReactDOMServer.renderToString(<ClassWithRenderNotExtended />),
).toThrow(TypeError);
assertConsoleErrorDev([
'The <ClassWithRenderNotExtended /> component appears to have a render method, ' +
"but doesn't extend React.Component. This is likely to cause errors. " +
'Change ClassWithRenderNotExtended to extend React.Component instead.\n' +
' in ClassWithRenderNotExtended (at **)',
]);
expect(() => {
ReactDOMServer.renderToString(<ClassWithRenderNotExtended />);
}).toThrow(TypeError);
});
it('can import react-dom in Node environment', () => {
if (
typeof requestAnimationFrame !== 'undefined' ||
global.hasOwnProperty('requestAnimationFrame') ||
typeof requestIdleCallback !== 'undefined' ||
global.hasOwnProperty('requestIdleCallback') ||
typeof window !== 'undefined' ||
global.hasOwnProperty('window')
) {
throw new Error('Expected this test to run in a Node environment.');
}
jest.resetModules();
expect(() => {
require('react-dom');
}).not.toThrow();
});
it('includes a useful stack in warnings', () => {
function A() {
return null;
}
function B() {
return (
<font>
<C>
<span ariaTypo="no" />
</C>
</font>
);
}
class C extends React.Component {
render() {
return <b>{this.props.children}</b>;
}
}
function Child() {
return [<A key="1" />, <B key="2" />, <span ariaTypo2="no" key="3" />];
}
function App() {
return (
<div>
<section />
<span>
<Child />
</span>
</div>
);
}
ReactDOMServer.renderToString(<App />);
assertConsoleErrorDev([
'Invalid ARIA attribute `ariaTypo`. ARIA attributes follow the pattern aria-* and must be lowercase.\n' +
' in span (at **)\n' +
' in B (at **)\n' +
' in Child (at **)\n' +
' in App (at **)',
'Invalid ARIA attribute `ariaTypo2`. ARIA attributes follow the pattern aria-* and must be lowercase.\n' +
' in span (at **)\n' +
' in Child (at **)\n' +
' in App (at **)',
]);
});
it('reports stacks with re-entrant renderToString() calls', () => {
function Child2(props) {
return <span ariaTypo3="no">{props.children}</span>;
}
function App2() {
return (
<Child2>
{ReactDOMServer.renderToString(<blink ariaTypo2="no" />)}
</Child2>
);
}
function Child() {
return (
<span ariaTypo4="no">{ReactDOMServer.renderToString(<App2 />)}</span>
);
}
function App() {
return (
<div>
<span ariaTypo="no" />
<Child />
<font ariaTypo5="no" />
</div>
);
}
ReactDOMServer.renderToString(<App />);
assertConsoleErrorDev([
'Invalid ARIA attribute `ariaTypo`. ARIA attributes follow the pattern aria-* and must be lowercase.\n' +
' in span (at **)\n' +
' in App (at **)',
'Invalid ARIA attribute `ariaTypo2`. ARIA attributes follow the pattern aria-* and must be lowercase.\n' +
' in blink (at **)\n' +
' in App2 (at **)\n' +
' in Child (at **)\n' +
' in App (at **)',
'Invalid ARIA attribute `ariaTypo3`. ARIA attributes follow the pattern aria-* and must be lowercase.\n' +
' in span (at **)\n' +
' in Child2 (at **)\n' +
' in App2 (at **)\n' +
' in Child (at **)\n' +
' in App (at **)',
'Invalid ARIA attribute `ariaTypo4`. ARIA attributes follow the pattern aria-* and must be lowercase.\n' +
' in span (at **)\n' +
' in Child (at **)\n' +
' in App (at **)',
'Invalid ARIA attribute `ariaTypo5`. ARIA attributes follow the pattern aria-* and must be lowercase.\n' +
' in font (at **)\n' +
' in App (at **)',
]);
});
it('should warn if an invalid contextType is defined', () => {
const Context = React.createContext();
class ComponentA extends React.Component {
static contextType = Context.Consumer;
render() {
return <div />;
}
}
ReactDOMServer.renderToString(<ComponentA />);
assertConsoleErrorDev([
'ComponentA defines an invalid contextType. ' +
'contextType should point to the Context object returned by React.createContext(). ' +
'Did you accidentally pass the Context.Consumer instead?\n' +
' in ComponentA (at **)',
]);
ReactDOMServer.renderToString(<ComponentA />);
class ComponentB extends React.Component {
static contextType = Context.Provider;
render() {
return <div />;
}
}
ReactDOMServer.renderToString(<ComponentB />);
});
it('should not warn when class contextType is null', () => {
class Foo extends React.Component {
static contextType = null;
render() {
return this.context.hello.world;
}
}
expect(() => {
ReactDOMServer.renderToString(<Foo />);
}).toThrow("Cannot read property 'world' of undefined");
});
it('should warn when class contextType is undefined', () => {
class Foo extends React.Component {
static contextType = undefined;
render() {
return this.context.hello.world;
}
}
expect(() => {
ReactDOMServer.renderToString(<Foo />);
}).toThrow("Cannot read property 'world' of undefined");
assertConsoleErrorDev([
'Foo defines an invalid contextType. ' +
'contextType should point to the Context object returned by React.createContext(). ' +
'However, it is set to undefined. ' +
'This can be caused by a typo or by mixing up named and default imports. ' +
'This can also happen due to a circular dependency, ' +
'so try moving the createContext() call to a separate file.\n' +
' in Foo (at **)',
]);
});
it('should warn when class contextType is an object', () => {
class Foo extends React.Component {
static contextType = {
x: 42,
y: 'hello',
};
render() {
return this.context.hello.world;
}
}
expect(() => {
ReactDOMServer.renderToString(<Foo />);
}).toThrow("Cannot read property 'hello' of undefined");
assertConsoleErrorDev([
'Foo defines an invalid contextType. ' +
'contextType should point to the Context object returned by React.createContext(). ' +
'However, it is set to an object with keys {x, y}.\n' +
' in Foo (at **)',
]);
});
it('should warn when class contextType is a primitive', () => {
class Foo extends React.Component {
static contextType = 'foo';
render() {
return this.context.hello.world;
}
}
expect(() => {
ReactDOMServer.renderToString(<Foo />);
}).toThrow("Cannot read property 'world' of undefined");
assertConsoleErrorDev([
'Foo defines an invalid contextType. ' +
'contextType should point to the Context object returned by React.createContext(). ' +
'However, it is set to a string.\n' +
' in Foo (at **)',
]);
});
describe('custom element server rendering', () => {
it('String properties should be server rendered for custom elements', () => {
const output = ReactDOMServer.renderToString(
<my-custom-element foo="bar" />,
);
expect(output).toBe(`<my-custom-element foo="bar"></my-custom-element>`);
});
it('Number properties should be server rendered for custom elements', () => {
const output = ReactDOMServer.renderToString(
<my-custom-element foo={5} />,
);
expect(output).toBe(`<my-custom-element foo="5"></my-custom-element>`);
});
it('Object properties should not be server rendered for custom elements', () => {
const output = ReactDOMServer.renderToString(
<my-custom-element foo={{foo: 'bar'}} />,
);
expect(output).toBe(`<my-custom-element></my-custom-element>`);
});
it('Array properties should not be server rendered for custom elements', () => {
const output = ReactDOMServer.renderToString(
<my-custom-element foo={['foo', 'bar']} />,
);
expect(output).toBe(`<my-custom-element></my-custom-element>`);
});
it('Function properties should not be server rendered for custom elements', () => {
const output = ReactDOMServer.renderToString(
<my-custom-element foo={() => console.log('bar')} />,
);
expect(output).toBe(`<my-custom-element></my-custom-element>`);
});
});
});