From 3166c2a56cb6288fe2b6b14bf55add696c350b4b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dandelion=20Man=C3=A9?= <dl@dandelion.io>
Date: Tue, 8 May 2018 14:56:06 -0700
Subject: [PATCH] Turn on flow for config/env.js (#243)

It was doing some clever array construction that added possible booleans
to the array, then filtered them out. To make the typing simpler for
Flow's inspection, we now only put string elements in the array.

Test plan: `yarn travis --full` passed, and the CLI still works.
---
 config/env.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/config/env.js b/config/env.js
index 0588b3f..e6128e3 100644
--- a/config/env.js
+++ b/config/env.js
@@ -1,4 +1,4 @@
-// @no-flow
+// @flow
 const fs = require("fs");
 const path = require("path");
 const paths = require("./paths");
@@ -20,9 +20,9 @@ var dotenvFiles = [
   // Don't include `.env.local` for `test` environment
   // since normally you expect tests to produce the same
   // results for everyone
-  NODE_ENV !== "test" && `${paths.dotenv}.local`,
+  ...(NODE_ENV !== "test" ? [`${paths.dotenv}.local`] : []),
   paths.dotenv,
-].filter(Boolean);
+];
 
 // Load environment variables from .env* files. Suppress warnings using silent
 // if this file is missing. dotenv will never modify any environment variables
@@ -59,7 +59,7 @@ process.env.NODE_PATH = (process.env.NODE_PATH || "")
 // injected into the application via DefinePlugin in Webpack configuration.
 const REACT_APP = /^REACT_APP_/i;
 
-function getClientEnvironment(publicUrl) {
+function getClientEnvironment(publicUrl /*: string */) {
   const raw = Object.keys(process.env)
     .filter((key) => REACT_APP.test(key))
     .reduce(