Migrate environmentVariables

Summary: _typescript_

Reviewed By: jknoxville

Differential Revision: D16709690

fbshipit-source-id: efa0431ab1ab0e2fc81ae4a9155d2f0a3ab9e4c5

src/utils/__tests__/environmentVariables.node.js

@@ -5,7 +5,7 @@
  * @format
  */
 
-import {parseFlipperPorts} from '../environmentVariables';
+import {parseFlipperPorts} from '../environmentVariables.tsx';
 
 test('Valid port overrides are parsed correctly', () => {
   const overrides = parseFlipperPorts('1111,2222');

src/utils/environmentVariables.tsx

@@ -7,7 +7,7 @@
 
 export function parseFlipperPorts(
   envVar: string,
-): ?{insecure: number, secure: number} {
+): {insecure: number; secure: number} | undefined {
   const components = envVar.split(',');
   const ports = components.map(x => parseInt(x, 10));