features-detection.js

'use strict';
const {create, fragment, text} = require('./easy-dom.js');

const testFragment = fragment(document);

// DOM4 node.append(...many)
const hasAppend = 'append' in testFragment;
exports.hasAppend = hasAppend;

// detect old browsers without HTMLTemplateElement content support
const hasContent = 'content' in create(document, 'template');
exports.hasContent = hasContent;

// IE 11 has problems with cloning templates: it "forgets" empty childNodes
testFragment.appendChild(text(testFragment, 'g'));
testFragment.appendChild(text(testFragment, ''));
const hasDoomedCloneNode = testFragment.cloneNode(true).childNodes.length === 1;
exports.hasDoomedCloneNode = hasDoomedCloneNode;

// old browsers need to fallback to cloneNode
// Custom Elements V0 and V1 will work polyfilled
// but native implementations need importNode instead
// (specially Chromium and its old V0 implementation)
const hasImportNode = 'importNode' in document;
exports.hasImportNode = hasImportNode;