metro.config.js

const path = require('path');
const escape = require('escape-string-regexp');
const { getDefaultConfig } = require('@expo/metro-config');
const exclusionList = require('metro-config/src/defaults/exclusionList');
const pak = require('../package.json');

const root = path.resolve(__dirname, '..');

const modules = Object.keys({
  ...pak.peerDependencies,
});

const defaultConfig = getDefaultConfig(__dirname);

module.exports = {
  ...defaultConfig,

  projectRoot: __dirname,
  watchFolders: [root],

  transformer: {
    ...defaultConfig.transformer,
    babelTransformerPath: require.resolve('react-native-svg-transformer'),
  },
  // We need to make sure that only one version is loaded for peerDependencies
  // So we block them at the root, and alias them to the versions in example's node_modules
  resolver: {
    ...defaultConfig.resolver,

    blacklistRE: exclusionList(
      modules.map(
        m => new RegExp(`^${escape(path.join(root, 'node_modules', m))}\\/.*$`),
      ),
    ),

    extraNodeModules: modules.reduce((acc, name) => {
      acc[name] = path.join(__dirname, 'node_modules', name);
      return acc;
    }, {}),

    assetExts: defaultConfig.resolver.assetExts.filter(ext => ext !== 'svg'),
    sourceExts: [...defaultConfig.resolver.sourceExts, 'svg'],
  },
};