'use strict';
const React = require('react');
const ReactDOM = require('react-dom');
function expectWarnings(tags, warnings = [], withoutStack = 0) {
tags = [...tags];
warnings = [...warnings];
let element = null;
const containerTag = tags.shift();
const container =
containerTag === 'svg'
? document.createElementNS('http://www.w3.org/2000/svg', containerTag)
: document.createElement(containerTag);
while (tags.length) {
const Tag = tags.pop();
element = <Tag>{element}</Tag>;
}
if (warnings.length) {
expect(() => ReactDOM.render(element, container)).toErrorDev(warnings, {
withoutStack,
});
}
}
describe('validateDOMNesting', () => {
it('allows valid nestings', () => {
expectWarnings(['table', 'tbody', 'tr', 'td', 'b']);
expectWarnings(
['body', 'datalist', 'option'],
[
gate(flags => !flags.enableHostSingletons)
? 'render(): Rendering components directly into document.body is discouraged'
: null,
].filter(Boolean),
1,
);
expectWarnings(['div', 'a', 'object', 'a']);
expectWarnings(['div', 'p', 'button', 'p']);
expectWarnings(['p', 'svg', 'foreignObject', 'p']);
expectWarnings(['html', 'body', 'div']);
expectWarnings(['div', 'ul', 'ul', 'li']);
expectWarnings(['div', 'label', 'div']);
expectWarnings(['div', 'ul', 'li', 'section', 'li']);
expectWarnings(['div', 'ul', 'li', 'dd', 'li']);
});
it('prevents problematic nestings', () => {
expectWarnings(
['a', 'a'],
[
'validateDOMNesting(...): <a> cannot appear as a descendant of <a>.\n' +
' in a (at **)',
],
);
expectWarnings(
['form', 'form'],
[
'validateDOMNesting(...): <form> cannot appear as a descendant of <form>.\n' +
' in form (at **)',
],
);
expectWarnings(
['p', 'p'],
[
'validateDOMNesting(...): <p> cannot appear as a descendant of <p>.\n' +
' in p (at **)',
],
);
expectWarnings(
['table', 'tr'],
[
'validateDOMNesting(...): <tr> cannot appear as a child of <table>. ' +
'Add a <tbody>, <thead> or <tfoot> to your code to match the DOM tree generated by the browser.\n' +
' in tr (at **)',
],
);
expectWarnings(
['div', 'ul', 'li', 'div', 'li'],
[
'validateDOMNesting(...): <li> cannot appear as a descendant of <li>.\n' +
' in li (at **)\n' +
' in div (at **)\n' +
' in li (at **)\n' +
' in ul (at **)',
],
);
expectWarnings(
['div', 'html'],
[
'validateDOMNesting(...): <html> cannot appear as a child of <div>.\n' +
' in html (at **)',
],
);
if (gate(flags => flags.enableHostSingletons)) {
expectWarnings(
['body', 'body'],
[
'validateDOMNesting(...): <body> cannot appear as a child of <body>.\n' +
' in body (at **)',
],
);
} else {
expectWarnings(
['body', 'body'],
[
'render(): Rendering components directly into document.body is discouraged',
'validateDOMNesting(...): <body> cannot appear as a child of <body>.\n' +
' in body (at **)',
],
1,
);
}
if (gate(flags => flags.enableHostSingletons)) {
expectWarnings(
['svg', 'foreignObject', 'body', 'p'],
[
'validateDOMNesting(...): <body> cannot appear as a child of <foreignObject>.\n' +
' in body (at **)\n' +
' in foreignObject (at **)',
'Warning: You are mounting a new body component when a previous one has not first unmounted. It is an error to render more than one body component at a time and attributes and children of these components will likely fail in unpredictable ways. Please only render a single instance of <body> and if you need to mount a new one, ensure any previous ones have unmounted first.\n' +
' in body (at **)',
],
);
} else {
expectWarnings(
['svg', 'foreignObject', 'body', 'p'],
[
'validateDOMNesting(...): <body> cannot appear as a child of <foreignObject>.\n' +
' in body (at **)\n' +
' in foreignObject (at **)',
],
);
}
});
});