export function pathToHtmlSafeName(path: string) { return path.replace(/[^a-zA-Z0-9_]/g, '_'); } export function getHotReplaceTemplate(id: string) { // In dev mode, we need to replace the style tag instead of appending it // use the path as the expo-css-hmr attribute to find the style tag // to replace. const attr = JSON.stringify(pathToHtmlSafeName(id)); return `style.setAttribute('data-expo-css-hmr', ${attr}); const previousStyle = document.querySelector('[data-expo-css-hmr=${attr}]'); if (previousStyle) { previousStyle.parentNode.removeChild(previousStyle); }`; } export function wrapDevelopmentCSS(props: { src: string; filename: string }) { const withBackTicksEscaped = escapeBackticksAndOctals(props.src); return `(() => { if (typeof document === 'undefined') { return } const head = document.head || document.getElementsByTagName('head')[0]; const style = document.createElement('style'); ${getHotReplaceTemplate(props.filename)} style.setAttribute('data-expo-loader', 'css'); head.appendChild(style); const css = \`${withBackTicksEscaped}\`; if (style.styleSheet){ style.styleSheet.cssText = css; } else { style.appendChild(document.createTextNode(css)); } })();`; } export function escapeBackticksAndOctals(str: string) { if (typeof str !== 'string') { return ''; } return str .replace(/\\/g, '\\\\') .replace(/`/g, '\\`') .replace(/[\0-\7]/g, (match) => `\\0${match.charCodeAt(0).toString(8)}`); }