fix: remove deprecated existential Flow type and use any for now (#77)

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### Summary

Existential type (`*`) is long deprecated, let's just use `any` for now.

### Test plan

Added some more Flow typings to `shallow.test.js` that were failing because of existential type.

src/__tests__/__snapshots__/shallow.test.js.snap

@@ -13,7 +13,9 @@ exports[`shallow rendering React Test Instance 1`] = `
 `;
 
 exports[`shallow rendering React elements 1`] = `
-<View>
+<View
+  testID="2"
+>
   <Text
     testID="text-button"
   >

src/__tests__/shallow.test.js

@@ -3,14 +3,18 @@ import React from 'react';
 import { View, Text } from 'react-native';
 import { shallow, render } from '..';
 
-const TextPress = () => (
-  <View>
+type Props = {|
+  +dummyID?: string,
+|};
+
+const TextPress = ({ dummyID }: Props) => (
+  <View testID={dummyID}>
     <Text testID="text-button">Press me</Text>
   </View>
 );
 
 test('shallow rendering React elements', () => {
-  const { output } = shallow(<TextPress />);
+  const { output } = shallow(<TextPress dummyID="2" />);
 
   expect(output).toMatchSnapshot();
 });

src/debug.js

@@ -10,11 +10,11 @@ import format from './helpers/format';
  * Log pretty-printed deep test component instance
  */
 function debugDeepElementOrInstance(
-  instance: React.Element<*> | ?ReactTestRendererJSON,
+  instance: React.Element<any> | ?ReactTestRendererJSON,
   message?: any = ''
 ) {
   try {
-    // We're assuming React.Element<*> here and fallback to
+    // We're assuming React.Element<any> here and fallback to
     // rendering ?ReactTestRendererJSON
     // $FlowFixMe
     const { toJSON } = render(instance);
@@ -29,7 +29,10 @@ function debugDeepElementOrInstance(
   }
 }
 
-function debug(instance: ReactTestInstance | React.Element<*>, message?: any) {
+function debug(
+  instance: ReactTestInstance | React.Element<any>,
+  message?: any
+) {
   return debugShallow(instance, message);
 }
 

src/helpers/debugShallow.js

@@ -7,7 +7,7 @@ import format from './format';
  * Log pretty-printed shallow test component instance
  */
 export default function debugShallow(
-  instance: ReactTestInstance | React.Element<*>,
+  instance: ReactTestInstance | React.Element<any>,
   message?: any
 ) {
   const { output } = shallow(instance);

src/render.js

@@ -11,8 +11,8 @@ import debugDeep from './helpers/debugDeep';
  * to assert on the output.
  */
 export default function render(
-  component: React.Element<*>,
-  options?: { createNodeMock: (element: React.Element<*>) => any }
+  component: React.Element<any>,
+  options?: { createNodeMock: (element: React.Element<any>) => any }
 ) {
   const renderer = TestRenderer.create(component, options);
   const instance = renderer.root;

src/shallow.js

@@ -6,7 +6,7 @@ import ShallowRenderer from 'react-test-renderer/shallow'; // eslint-disable-lin
  * Renders test component shallowly using react-test-renderer/shallow
  */
 export default function shallow(
-  instance: ReactTestInstance | React.Element<*>
+  instance: ReactTestInstance | React.Element<any>
 ) {
   const renderer = new ShallowRenderer();