How to use jest-resolve - 5 common examples

const { resolve, extname, join, dirname, basename } = require('path');
const lwcResolver = require('@lwc/module-resolver');

/*
 * In Jest version 24 the default resolver was renamed to camelCase. Temporarily
 * support both file names until consumers upgrade their Jest version.
 *
 * Jest master branch has the default resolver passed as a param to custom
 * resolvers like this. Once that is released we can remove this entire block.
 * https://github.com/facebook/jest/commit/3f4661f141562aeca65cdad3802e930835dcf0d9
 */
let resolver;
try {
    resolver = require('jest-resolve/build/default_resolver').default;
} catch (e) {
    resolver = require('jest-resolve/build/defaultResolver').default;
}

const EMPTY_CSS_MOCK = resolve(__dirname, '..', 'resources', 'emptyStyleMock.js');
const EMPTY_HTML_MOCK = resolve(__dirname, '..', 'resources', 'emptyHtmlMock.js');

const WHITELISTED_LWC_PACKAGES = {
    lwc: '@lwc/engine',
    'wire-service': '@lwc/wire-service',
    'wire-service-jest-util': 'lwc-wire-service-jest-util',
};
const lwcMap = lwcResolver.resolveModules();

// This logic is somewhat the same in the compiler resolution system
// We should try to consolidate it at some point.
function isImplicitHTMLImport(importee, { basedir }) {
    const ext = extname(importee);

const { resolve, extname, join, dirname, basename } = require('path');
const lwcNpmResolver = require('@lwc/module-resolver');

/*
 * In Jest version 24 the default resolver was renamed to camelCase. Temporarily
 * support both file names until consumers upgrade their Jest version.
 *
 * Jest master branch has the default resolver passed as a param to custom
 * resolvers like this. Once that is released we can remove this entire block.
 * https://github.com/facebook/jest/commit/3f4661f141562aeca65cdad3802e930835dcf0d9
 */
let resolver;
try {
    resolver = require('jest-resolve/build/default_resolver').default;
} catch (e) {
    resolver = require('jest-resolve/build/defaultResolver').default;
}

const EMPTY_CSS_MOCK = resolve(__dirname, '..', 'resources', 'emptyStyleMock.js');
const EMPTY_HTML_MOCK = resolve(__dirname, '..', 'resources', 'emptyHtmlMock.js');

const WHITELISTED_LWC_PACKAGES = {
    lwc: '@lwc/engine',
    'wire-service': '@lwc/wire-service',
    'wire-service-jest-util': 'lwc-wire-service-jest-util',
};
const lwcMap = lwcNpmResolver.resolveLwcNpmModules();

// This logic is somewhat the same in the compiler resolution system
// We should try to consolidate it at some point.
function isImplicitHTMLImport(importee, { basedir }) {
    const ext = extname(importee);

module.exports = function(path: string, options: ResolveOptions) {
  const ext = extname(path);
  if (
    ext === '.css' ||
    ext === '.scss' ||
    ext === '.sass' ||
    ext === '.less' ||
    ext === '.styl'
  ) {
    return require.resolve('identity-obj-proxy');
  }
  // Try to use the defaultResolver
  try {
    return defaultResolver(path, options);
  } catch (e) {
    // Fallback to using typescript
    compilerSetup = compilerSetup || getCompilerSetup(options.rootDir);
    const { compilerOptions, host } = compilerSetup;
    return ts.resolveModuleName(path, options.basedir, compilerOptions, host)
      .resolvedModule.resolvedFileName;
  }
};

module.exports = (moduleName, options) => {
  const resolvedPath = resolver(moduleName, options);

  if (
    ReactTestVersion &&
    ['react', 'react-dom', 'react-test-renderer'].some(p =>
      resolvedPath.includes('node_modules/${}/')
    ) &&
    !resolvedPath.includes('react-versions/react')
  ) {
    return resolvedPath.replace(
      'node_modules/',
      `react-versions/react-${ReactTestVersion}/node_modules/`
    );
  }

  return resolvedPath;
};

module.exports = function (path, options) {
    return defaultResolver(getLwcPath(path, options), options);
};