change `isPolyfill` to `type = 'module' | 'script'`

Summary: When building, we will process modules in a special way, *not* polyfillys. We will also add more types of (virtual) files that are not modules. That’s why a “type” property makes more sense.

Reviewed By: cpojer

Differential Revision: D4244583

fbshipit-source-id: 92a0b4a0a2026d0b97ba88034483a6ce4e0c1ebb

packager/react-packager/src/ModuleGraph/Graph.js

@@ -50,7 +50,7 @@ type LoadQueue =
  Async$Queue<{id: string, parent: string}, Callback<File, Array<string>>>;

const createParentModule =
  () => ({file: {code: '', isPolyfill: false, path: ''}, dependencies: []});
  () => ({file: {code: '', type: 'script', path: ''}, dependencies: []});

const noop = () => {};
const NO_OPTIONS = {};

packager/react-packager/src/ModuleGraph/types.flow.js

@@ -40,11 +40,13 @@ type Dependency = {|

export type File = {|
  code: string,
  isPolyfill: boolean,
  map?: ?Object,
  path: string,
  type: FileTypes,
|};

type FileTypes = 'module' | 'script';

export type Module = {|
  dependencies: Array<Dependency>,
  file: File,
@@ -82,9 +84,9 @@ export type TransformedFile = {
  code: string,
  file: string,
  hasteID: ?string,
  isPolyfill: boolean,
  package?: PackageData,
  transformed: {[variant: string]: TransformResult},
  type: FileTypes,
};

export type PackageData = {|

packager/react-packager/src/ModuleGraph/worker/__tests__/transform-module-test.js

@@ -62,16 +62,16 @@ describe('transforming JS modules:', () => {
    });
  });

  it('sets `isPolyfill` to `false` by default', done => {
  it('sets `type` to `"module"` by default', done => {
    transformModule(sourceCode, options(), (error, result) => {
      expect(result).toEqual(objectContaining({isPolyfill: false}));
      expect(result).toEqual(objectContaining({type: 'module'}));
      done();
    });
  });

  it('sets `isPolyfill` to `true` if the input is a polyfill', done => {
  it('sets `type` to `"script"` if the input is a polyfill', done => {
    transformModule(sourceCode, {...options(), polyfill: true}, (error, result) => {
      expect(result).toEqual(objectContaining({isPolyfill: true}));
      expect(result).toEqual(objectContaining({type: 'script'}));
      done();
    });
  });

packager/react-packager/src/ModuleGraph/worker/transform-module.js

@@ -75,9 +75,9 @@ function transformModule(
    callback(null, {
      code,
      file: filename,
      isPolyfill: !!options.polyfill,
      hasteID: annotations.providesModule || annotations.provide || null,
      transformed,
      type: options.polyfill ? 'script' : 'module',
    });
  });
}
@@ -105,8 +105,8 @@ function transformJSON(json, options, callback) {
    code: json,
    file: filename,
    hasteID: value.name,
    isPolyfill: false,
    transformed,
    type: 'module',
  };

  if (basename(filename) === 'package.json') {