Repository: facebook/jest
File: packages/jest-resolve/src/resolver.ts (TypeScript)

Code before:
  ): string | null {
    const {extensions, key, moduleDirectory, paths, skipResolution} =
      this._prepareForResolution(dirname, moduleName, options);

    let module;

    // 1. If we have already resolved this module for this directory name,
    // return a value from the cache.
    const cacheResult = this._moduleNameCache.get(key);
    if (cacheResult) {
      return cacheResult;
    }

    // 2. Check if the module is a haste module.
    module = this.getModule(moduleName);
    if (module) {
      this._moduleNameCache.set(key, module);
      return module;
    }

    // 3. Check if the module is a node module and resolve it based on
    // the node module resolution algorithm. If skipNodeResolution is given we
    // ignore all modules that look like node modules (ie. are not relative
    // requires). This enables us to speed up resolution when we build a
    // dependency graph because we don't have to look at modules that may not
    // exist and aren't mocked.waq
    const resolveNodeModule = (name: string, throwIfNotFound = false) => {
      if (this.isCoreModule(name) && !this._options.resolver) {
        return name;
      }

      return Resolver.findNodeModule(name, {
        basedir: dirname,
        conditions: options?.conditions,
        extensions,
        moduleDirectory,
        paths,
        resolver: this._options.resolver,
        rootDir: this._options.rootDir,
        throwIfNotFound,
      });
    };

    if (!skipResolution) {
      module = resolveNodeModule(moduleName, Boolean(process.versions.pnp));

      if (module) {
        this._moduleNameCache.set(key, module);
        return module;
      }
    }

Review comment (suggestion):
```suggestion
    // exist and aren't mocked.
```

Code after:
  ): string | null {
    const {extensions, key, moduleDirectory, paths, skipResolution} =
      this._prepareForResolution(dirname, moduleName, options);

    let module;

    // 1. If we have already resolved this module for this directory name,
    // return a value from the cache.
    const cacheResult = this._moduleNameCache.get(key);
    if (cacheResult) {
      return cacheResult;
    }

    // 2. Check if the module is a haste module.
    module = this.getModule(moduleName);
    if (module) {
      this._moduleNameCache.set(key, module);
      return module;
    }

    // 3. Check if the module is a node module and resolve it based on
    // the node module resolution algorithm. If skipNodeResolution is given we
    // ignore all modules that look like node modules (ie. are not relative
    // requires). This enables us to speed up resolution when we build a
    // dependency graph because we don't have to look at modules that may not
    // exist and aren't mocked.
    const resolveNodeModule = (name: string, throwIfNotFound = false) => {
      // Only skip default resolver
      if (this.isCoreModule(name) && !this._options.resolver) {
        return name;
      }

      return Resolver.findNodeModule(name, {
        basedir: dirname,
        conditions: options?.conditions,
        extensions,
        moduleDirectory,
        paths,
        resolver: this._options.resolver,
        rootDir: this._options.rootDir,
        throwIfNotFound,
      });
    };

    if (!skipResolution) {
      module = resolveNodeModule(moduleName, Boolean(process.versions.pnp));

      if (module) {
        this._moduleNameCache.set(key, module);
        return module;
      }