diff --git a/src/client.js b/src/client.js index f3da4667..cd1ba307 100644 --- a/src/client.js +++ b/src/client.js @@ -6,13 +6,6 @@ import './routes/_utils/historyEvents' import './routes/_utils/loadingMask' import './routes/_utils/forceOnline' -// TODO: when some browser supports :focus-visible, feature-detect and async load polyfill -// Firefox: https://bugzilla.mozilla.org/show_bug.cgi?id=1445482 -// WebKit: https://bugs.webkit.org/show_bug.cgi?id=185859 -// Chrome: https://bugs.chromium.org/p/chromium/issues/detail?id=817199 -// Chrome ITS: https://groups.google.com/a/chromium.org/forum/#!msg/blink-dev/XKNtAVyO4AY/ujOrvaYsBwAJ -import 'focus-visible' - loadPolyfills().then(() => { console.log('init()') sapper.start({ target: document.querySelector('#sapper') }) diff --git a/src/routes/_utils/asyncPolyfills.js b/src/routes/_utils/asyncPolyfills.js index 7047db0c..844d0bc0 100644 --- a/src/routes/_utils/asyncPolyfills.js +++ b/src/routes/_utils/asyncPolyfills.js @@ -17,3 +17,7 @@ export const importCustomElementsPolyfill = () => import( export const importIntl = () => import( /* webpackChunkName: '$polyfill$-intl' */ 'intl' ) + +export const importFocusVisible = () => import( + /* webpackChunkName: '$polyfill$-focus-visible' */ 'focus-visible' +) diff --git a/src/routes/_utils/loadPolyfills.js b/src/routes/_utils/loadPolyfills.js index b9a9515d..0a9b0de3 100644 --- a/src/routes/_utils/loadPolyfills.js +++ b/src/routes/_utils/loadPolyfills.js @@ -1,10 +1,12 @@ import { importCustomElementsPolyfill, + importFocusVisible, importIndexedDBGetAllShim, importIntersectionObserver, importIntl, importRequestIdleCallback } from './asyncPolyfills' +import { supportsSelector } from './supportsSelector' export function loadPolyfills () { return Promise.all([ @@ -12,6 +14,7 @@ export function loadPolyfills () { typeof requestIdleCallback === 'undefined' && importRequestIdleCallback(), !IDBObjectStore.prototype.getAll && importIndexedDBGetAllShim(), typeof customElements === 'undefined' && importCustomElementsPolyfill(), - process.env.LEGACY && typeof Intl === 'undefined' && importIntl() + process.env.LEGACY && typeof Intl === 'undefined' && importIntl(), + !supportsSelector(':focus-visible') && importFocusVisible() ]) } diff --git a/src/routes/_utils/supportsSelector.js b/src/routes/_utils/supportsSelector.js new file mode 100644 index 00000000..b36e6783 --- /dev/null +++ b/src/routes/_utils/supportsSelector.js @@ -0,0 +1,13 @@ +// See https://stackoverflow.com/a/8533927 +export function supportsSelector (selector) { + const style = document.createElement('style') + document.head.appendChild(style) + try { + style.sheet.insertRule(selector + '{}', 0) + } catch (e) { + return false + } finally { + document.head.removeChild(style) + } + return true +}