@soleil-se/build-app/rollup/api/getSveltePlugin.js

Script for building WebApps, RESTApps and Widgets with Svelte in Sitevision.

import { dirname } from 'path';
import { findUpSync } from 'find-up';
import fse from 'fs-extra';
import { kebabCase } from 'lodash-es';
import { createRequire } from 'module';

import preprocessOptions from './common/preprocessOptions.js';

const validClassRegex = /[^a-z0-9\-_]|^[^a-z]+/gi;

function hasSvelte(input) {
  const packageFile = findUpSync('package.json', { cwd: dirname(input) });
  const { dependencies = {} } = fse.readJSONSync(packageFile);
  return Object.keys(dependencies).includes('svelte');
}

/* Custom CSS hash requires version 3.34.0 or later */
function cssHash({ hash, css, name }) {
  const validClass = name.replace(validClassRegex, '');
  return `${kebabCase(validClass)}-${hash(css)}`;
}

async function getSvelteConfig() {
  const svelteConfigPath = findUpSync(['svelte.config.js', 'svelte.config.cjs', 'svelte.config.mjs']);
  return svelteConfigPath ? import(`file://${svelteConfigPath}`).then((pkg) => pkg.default) : {};
}

async function getPreprocess(svelteConfig) {
  if (svelteConfig.preprocess) return svelteConfig.preprocess;
  const sveltePreprocess = await import('svelte-preprocess').then((pkg) => pkg.default);
  return sveltePreprocess(preprocessOptions);
}

function isLegacy() {
  const require = createRequire(import.meta.url);
  // eslint-disable-next-line import/no-extraneous-dependencies
  const { version } = require('svelte/package.json');
  return version.startsWith('3') || version.startsWith('4');
}

export default async function getSveltePlugin({
  input, debug = false, extractCss = true, ssr, hydratable = true,
}) {
  if (hasSvelte(input)) {
    const svelte = await import('rollup-plugin-svelte').then((pkg) => pkg.default);

    const svelteConfig = await getSvelteConfig();
    return svelte({
      preprocess: await getPreprocess(svelteConfig),
      emitCss: extractCss,
      compilerOptions: {
        css: !extractCss ? 'injected' : undefined,
        ...svelteConfig.compilerOptions,
        generate: ssr ? 'server' : 'client',
        dev: debug,
        cssHash,
        ...(isLegacy() ? {
          enableSourcemap: debug,
          hydratable,
          generate: ssr ? 'ssr' : 'dom',
        } : {}),
      },
    });
  }
  return false;
}