function lazyRoutesTest() {
  const basePath = path.join(__dirname, '../ngtools_src');
  const project = path.join(basePath, 'tsconfig-build.json');

  const config = tsc.readConfiguration(project, basePath);
  const host = ts.createCompilerHost(config.parsed.options, true);
  const program = ts.createProgram(config.parsed.fileNames, config.parsed.options, host);

  config.ngOptions.basePath = basePath;

  const lazyRoutes = __NGTOOLS_PRIVATE_API_2.listLazyRoutes({
    program,
    host,
    angularCompilerOptions: config.ngOptions,
    entryModule: 'app.module#AppModule'
  });

  const expectations: {[route: string]: string} = {
    './lazy.module#LazyModule': 'lazy.module.ts',
    './feature/feature.module#FeatureModule': 'feature/feature.module.ts',
    './feature/lazy-feature.module#LazyFeatureModule': 'feature/lazy-feature.module.ts',
    './feature.module#FeatureModule': 'feature/feature.module.ts',
    './lazy-feature-nested.module#LazyFeatureNestedModule': 'feature/lazy-feature-nested.module.ts',
    'feature2/feature2.module#Feature2Module': 'feature2/feature2.module.ts',
    './default.module': 'feature2/default.module.ts',
    'feature/feature.module#FeatureModule': 'feature/feature.module.ts'
  };

  Object.keys(lazyRoutes).forEach((route: string) => {
    assert(route in expectations, `Found a route that was not expected: "${route}".`);
    assert(
        lazyRoutes[route] == path.join(basePath, expectations[route]),
        `Route "${route}" does not point to the expected absolute path ` +
            `"${path.join(basePath, expectations[route])}". It points to "${lazyRoutes[route]}"`);
  });

  // Verify that all expectations were met.
  assert.deepEqual(
      Object.keys(lazyRoutes), Object.keys(expectations), `Expected routes listed to be: \n` +
          `  ${JSON.stringify(Object.keys(expectations))}\n` +
          `Actual:\n` +
          `  ${JSON.stringify(Object.keys(lazyRoutes))}\n`);
}

function codeGenTest(forceError = false) {
  const basePath = path.join(__dirname, '../ngtools_src');
  const srcPath = path.join(__dirname, '../src');
  const project = path.join(basePath, 'tsconfig-build.json');
  const readResources: string[] = [];
  const wroteFiles: string[] = [];

  const config = tsc.readConfiguration(project, basePath);
  const hostContext = new NodeCompilerHostContext();
  const delegateHost = ts.createCompilerHost(config.parsed.options, true);
  const host: ts.CompilerHost = Object.assign(
      {}, delegateHost,
      {writeFile: (fileName: string, ...rest: any[]) => { wroteFiles.push(fileName); }});
  const program = ts.createProgram(config.parsed.fileNames, config.parsed.options, host);

  config.ngOptions.basePath = basePath;

  console.log(`>>> running codegen for ${project}`);
  if (forceError) {
    console.log(`>>> asserting that missingTranslation param with error value throws`);
  }
  return __NGTOOLS_PRIVATE_API_2
      .codeGen({
        basePath,
        compilerOptions: config.parsed.options, program, host,

        angularCompilerOptions: config.ngOptions,

        // i18n options.
        i18nFormat: 'xlf',
        i18nFile: path.join(srcPath, 'messages.fi.xlf'),
        locale: 'fi',
        missingTranslation: forceError ? 'error' : 'ignore',

        readResource: (fileName: string) => {
          readResources.push(fileName);
          return hostContext.readResource(fileName);
        }
      })
      .then(() => {
        console.log(`>>> codegen done, asserting read and wrote files`);

        // Assert for each file that it has been read and each `ts` has a written file associated.
        const allFiles = glob.sync(path.join(basePath, '**/*'), {nodir: true});

        allFiles.forEach((fileName: string) => {
          // Skip tsconfig.
          if (fileName.match(/tsconfig-build.json$/)) {
            return;
          }

          // Assert that file was read.
          if (fileName.match(/\.module\.ts$/)) {
            const factory = fileName.replace(/\.module\.ts$/, '.module.ngfactory.ts');
            assert(wroteFiles.indexOf(factory) != -1, `Expected file "${factory}" to be written.`);
          } else if (fileName.match(/\.css$/) || fileName.match(/\.html$/)) {
            assert(
                readResources.indexOf(fileName) != -1,
                `Expected resource "${fileName}" to be read.`);
          }
        });

        console.log(`done, no errors.`);
      })
      .catch((e: Error) => {
        if (forceError) {
          assert(
              e.message.match(`Missing translation for message`),
              `Expected error message for missing translations`);
          console.log(`done, error catched`);
        } else {
          console.error(e.stack);
          console.error('Compilation failed');
          throw e;
        }
      });
}

function i18nTest() {
  const basePath = path.join(__dirname, '../ngtools_src');
  const project = path.join(basePath, 'tsconfig-build.json');
  const readResources: string[] = [];
  const wroteFiles: string[] = [];

  const config = tsc.readConfiguration(project, basePath);
  const hostContext = new NodeCompilerHostContext();
  const delegateHost = ts.createCompilerHost(config.parsed.options, true);
  const host: ts.CompilerHost = Object.assign(
      {}, delegateHost,
      {writeFile: (fileName: string, ...rest: any[]) => { wroteFiles.push(fileName); }});
  const program = ts.createProgram(config.parsed.fileNames, config.parsed.options, host);

  config.ngOptions.basePath = basePath;

  console.log(`>>> running i18n extraction for ${project}`);
  return __NGTOOLS_PRIVATE_API_2
      .extractI18n({
        basePath,
        compilerOptions: config.parsed.options, program, host,
        angularCompilerOptions: config.ngOptions,
        i18nFormat: 'xlf',
        locale: undefined,
        outFile: undefined,
        readResource: (fileName: string) => {
          readResources.push(fileName);
          return hostContext.readResource(fileName);
        },
      })
      .then(() => {
        console.log(`>>> i18n extraction done, asserting read and wrote files`);

        const allFiles = glob.sync(path.join(basePath, '**/*'), {nodir: true});

        assert(wroteFiles.length == 1, `Expected a single message bundle file.`);

        assert(
            wroteFiles[0].endsWith('/ngtools_src/messages.xlf'),
            `Expected the bundle file to be "message.xlf".`);

        allFiles.forEach((fileName: string) => {
          // Skip tsconfig.
          if (fileName.match(/tsconfig-build.json$/)) {
            return;
          }

          // Assert that file was read.
          if (fileName.match(/\.css$/) || fileName.match(/\.html$/)) {
            assert(
                readResources.indexOf(fileName) != -1,
                `Expected resource "${fileName}" to be read.`);
          }
        });

        console.log(`done, no errors.`);
      })
      .catch((e: Error) => {
        console.error(e.stack);
        console.error('Extraction failed');
        throw e;
      });
}

 it('should allow to emit the program after analyzing routes', () => {
   writeSomeRoutes();
   const {program, host, options} = createProgram(['src/main.ts']);
   NgTools_InternalApi_NG_2.listLazyRoutes({
     program,
     host,
     angularCompilerOptions: options,
     entryModule: 'src/main#MainModule',
   });
   program.emit();
   testSupport.shouldExist('built/src/main.js');
 });

 fixmeIvy('FW-629: ngtsc lists lazy routes') && it('should list lazy routes recursively', () => {
   writeSomeRoutes();
   const {program, host, options} = createProgram(['src/main.ts']);
   const routes = NgTools_InternalApi_NG_2.listLazyRoutes({
     program,
     host,
     angularCompilerOptions: options,
     entryModule: 'src/main#MainModule',
   });
   expect(routes).toEqual({
     './child#ChildModule': path.resolve(testSupport.basePath, 'src/child.ts'),
     './child2#ChildModule2': path.resolve(testSupport.basePath, 'src/child2.ts'),
   });
 });