Function findAndReadConfig

src/configuration.ts:59–118

(rawOptions: CreateOptions)

/** @internal */
export function findAndReadConfig(rawOptions: CreateOptions) {
  const cwd = resolve(
    rawOptions.cwd ?? rawOptions.dir ?? DEFAULTS.cwd ?? process.cwd()
  );
  const compilerName = rawOptions.compiler ?? DEFAULTS.compiler;

  // Compute minimum options to read the config file.
  let projectLocalResolveDir = getBasePathForProjectLocalDependencyResolution(
    undefined,
    rawOptions.projectSearchDir,
    rawOptions.project,
    cwd
  );
  let { compiler, ts } = resolveAndLoadCompiler(
    compilerName,
    projectLocalResolveDir
  );

  // Read config file and merge new options between env and CLI options.
  const { configFilePath, config, tsNodeOptionsFromTsconfig, optionBasePaths } =
    readConfig(cwd, ts, rawOptions);

  const options = assign<RegisterOptions>(
    {},
    DEFAULTS,
    tsNodeOptionsFromTsconfig || {},
    { optionBasePaths },
    rawOptions
  );
  options.require = [
    ...(tsNodeOptionsFromTsconfig.require || []),
    ...(rawOptions.require || []),
  ];

  // Re-resolve the compiler in case it has changed.
  // Compiler is loaded relative to tsconfig.json, so tsconfig discovery may cause us to load a
  // different compiler than we did above, even if the name has not changed.
  if (configFilePath) {
    projectLocalResolveDir = getBasePathForProjectLocalDependencyResolution(
      configFilePath,
      rawOptions.projectSearchDir,
      rawOptions.project,
      cwd
    );
    ({ compiler } = resolveCompiler(
      options.compiler,
      optionBasePaths.compiler ?? projectLocalResolveDir
    ));
  }

  return {
    options,
    config,
    projectLocalResolveDir,
    optionBasePaths,
    configFilePath,
    cwd,
    compiler,