Summary:
Fixes the Flow failure due to an undefined Ast type.
Before:
```
$ npm run flow -- check
> react-native@1000.0.0 flow /Users/hramos/git/react-native
> flow "check"
Error: local-cli/__tests__/fs-mock-test.js:27
27: beforeEach(() => {
^^^^^^^^^^ beforeEach. Could not resolve name
Error: local-cli/__tests__/fs-mock-test.js:53
53: expect(content).toEqual('beep');
^^^^^^ expect. Could not resolve name
Error: local-cli/__tests__/fs-mock-test.js:88
88: expect(content).toEqual('hello, world!');
^^^^^^ expect. Could not resolve name
Error: local-cli/__tests__/fs-mock-test.js:100
100: expect(content).toEqual('hello, world!');
^^^^^^ expect. Could not resolve name
Error: node_modules/metro/src/Bundler/util.js.flow:46
46: ): Ast {
^^^ Ast. Could not resolve name
Error: node_modules/metro/src/ModuleGraph/worker/collect-dependencies.js.flow:283
283: const xp = (module.exports = (ast: Ast) =>
^^^ Ast. Could not resolve name
Error: node_modules/metro/src/assetTransformer.js.flow:29
29: ): Promise<{ast: Ast}> {
^^^ Ast. Could not resolve name
```
After
```
$ npm run flow -- check
> react-native@1000.0.0 flow /Users/hramos/git/react-native
> flow "check"
Error: local-cli/__tests__/fs-mock-test.js:27
27: beforeEach(() => {
^^^^^^^^^^ beforeEach. Could not resolve name
Error: local-cli/__tests__/fs-mock-test.js:53
53: expect(content).toEqual('beep');
^^^^^^ expect. Could not resolve name
Error: local-cli/__tests__/fs-mock-test.js:88
88: expect(content).toEqual('hello, world!');
^^^^^^ expect. Could not resolve name
Error: local-cli/__tests__/fs-mock-test.js:100
100: expect(content).toEqual('hello, world!');
^^^^^^ expect. Could not resolve name
```
[ GENERAL ] [ BUGFIX] [ .flowconfig ] - Have Flow ignore Metro node_nodules
Closes https://github.com/facebook/react-native/pull/17187
Differential Revision: D6572303
Pulled By: hramos
fbshipit-source-id: aa256b9725970fcc2a6da6578c83e7c0875e3cfd
f4d627c8fa