Integrate Flow typing

.flowconfig

@@ -0,0 +1,12 @@
+[ignore]
+
+[include]
+
+[libs]
+
+[lints]
+
+[options]
+module.name_mapper.extension='scss' -> '<PROJECT_ROOT>/src/flow/CSSModuleStub.js'
+
+[strict]

README.md

@@ -34,6 +34,7 @@
 + [Netlify CMS](https://www.netlifycms.org) support.
 + Google Analytics.
 + Disqus Comments.
++ [Flow](https://flow.org/) static type checking.
 
 ## Quick Start
 

gatsby-config.js

@@ -185,6 +185,7 @@ module.exports = {
           camelCase: false,
         }
       }
-    }
+    },
+    'gatsby-plugin-flow',
   ]
 };

package.json

@@ -8,9 +8,10 @@
     "build": "yarn run clean && gatsby build",
     "deploy": "yarn run clean && gatsby build --prefix-paths && gh-pages -d public",
     "clean": "rimraf .cache public",
+    "flow": "flow",
     "lint:js": "eslint --cache --ext .js,.jsx --ignore-pattern public .",
     "lint:scss": "stylelint \"src/**/*.scss\"",
-    "lint": "concurrently \"yarn run lint:js\" \"yarn run lint:scss\"",
+    "lint": "concurrently \"yarn run lint:js\" \"yarn run lint:scss\" \"yarn flow\"",
     "test": "jest --config ./tests/jest-config.js",
     "test:coverage": "jest --coverage --config ./tests/jest-config.js",
     "test:watch": "jest --watch --config ./tests/jest-config.js"
@@ -44,6 +45,7 @@
     "gatsby-link": "^2.0.16",
     "gatsby-plugin-catch-links": "^2.0.13",
     "gatsby-plugin-feed": "^2.1.0",
+    "gatsby-plugin-flow": "^1.0.4",
     "gatsby-plugin-google-gtag": "^1.0.16",
     "gatsby-plugin-manifest": "^2.0.26",
     "gatsby-plugin-netlify": "^2.0.13",
@@ -78,34 +80,36 @@
     "react-helmet": "^5.2.0"
   },
   "devDependencies": {
-    "@babel/plugin-proposal-optional-chaining": "7.0.0",
+    "@babel/core": "7.0.0",
     "@babel/plugin-proposal-class-properties": "7.0.0",
+    "@babel/plugin-proposal-optional-chaining": "7.0.0",
+    "@babel/plugin-transform-flow-strip-types": "^7.4.0",
     "@babel/preset-env": "7.0.0",
     "@babel/preset-react": "7.0.0",
-    "@babel/core": "7.0.0",
+    "autoprefixer": "9.5.1",
     "babel-core": "7.0.0-bridge.0",
+    "babel-eslint": "10.0.1",
     "babel-jest": "23.6.0",
-    "identity-obj-proxy": "3.0.0",
-    "react-test-renderer": "16.8.6",
-    "jest": "23.6.0",
-    "jest-cli": "23.6.0",
-    "rimraf": "2.6.3",
+    "browserslist": "4.5.4",
     "concurrently": "4.1.0",
-    "stylelint": "9.10.1",
-    "stylelint-scss": "3.5.4",
-    "stylelint-config-recommended-scss": "3.2.0",
     "eslint": "5.16.0",
     "eslint-config-airbnb-base": "13.1.0",
-    "eslint-plugin-jsx-a11y": "6.2.1",
     "eslint-plugin-import": "2.16.0",
     "eslint-plugin-jest": "22.4.1",
+    "eslint-plugin-jsx-a11y": "6.2.1",
     "eslint-plugin-react": "7.12.4",
     "eslint-watch": "5.0.1",
-    "babel-eslint": "10.0.1",
+    "flow-bin": "^0.96.0",
     "gh-pages": "2.0.1",
+    "identity-obj-proxy": "3.0.0",
+    "jest": "23.6.0",
+    "jest-cli": "23.6.0",
     "lost": "8.3.1",
     "postcss-pxtorem": "4.0.1",
-    "autoprefixer": "9.5.1",
-    "browserslist": "4.5.4"
+    "react-test-renderer": "16.8.6",
+    "rimraf": "2.6.3",
+    "stylelint": "9.10.1",
+    "stylelint-config-recommended-scss": "3.2.0",
+    "stylelint-scss": "3.5.4"
   }
 }

src/components/Sidebar/Sidebar.js

@@ -1,3 +1,4 @@
+// @flow
 import React from 'react';
 import { graphql, StaticQuery } from 'gatsby';
 import Author from './Author';
@@ -6,7 +7,15 @@ import Copyright from './Copyright';
 import Menu from './Menu';
 import styles from './Sidebar.module.scss';
 
-export const PureSidebar = ({ data, isIndex }) => {
+type Props = {
+  +isIndex: ?boolean,
+};
+
+type PureProps = Props & {
+  +data: Object,
+};
+
+export const PureSidebar = ({ data, isIndex }: PureProps) => {
   const {
     author,
     copyright,
@@ -25,7 +34,7 @@ export const PureSidebar = ({ data, isIndex }) => {
   );
 };
 
-export const Sidebar = (props) => (
+export const Sidebar = (props: Props) => (
   <StaticQuery
     query={graphql`
       query SidebarQuery {
@@ -42,7 +51,7 @@ export const Sidebar = (props) => (
               name
               photo
               bio
-              contacts {       
+              contacts {
                 twitter
                 telegram
                 github

src/flow/CSSModuleStub.js

@@ -0,0 +1,6 @@
+// @flow
+type CSSModule = {
+  [key: string]: string,
+};
+const emptyCSSModule: CSSModule = {};
+export default emptyCSSModule;

src/templates/index-template.js

@@ -1,3 +1,4 @@
+// @flow
 import React from 'react';
 import { graphql } from 'gatsby';
 import Layout from '../components/Layout';
@@ -6,7 +7,12 @@ import Feed from '../components/Feed';
 import Page from '../components/Page';
 import Pagination from '../components/Pagination';
 
-const IndexTemplate = ({ data, pageContext }) => {
+type Props = {
+  +data: Object,
+  +pageContext: Object,
+};
+
+const IndexTemplate = ({ data, pageContext }: Props) => {
   const {
     title: siteTitle,
     subtitle: siteSubtitle

tests/jest-preprocess.js

@@ -4,8 +4,9 @@ const babelOptions = {
   presets: ['@babel/react', '@babel/env'],
   plugins: [
     '@babel/plugin-proposal-optional-chaining',
-    '@babel/plugin-proposal-class-properties'
+    '@babel/plugin-proposal-class-properties',
+    '@babel/plugin-transform-flow-strip-types',
   ],
 };
 
-module.exports = require('babel-jest').createTransformer(babelOptions);
+module.exports = require('babel-jest').createTransformer(babelOptions);

yarn.lock

@@ -586,6 +586,14 @@
     "@babel/helper-plugin-utils" "^7.0.0"
     "@babel/plugin-syntax-flow" "^7.2.0"
 
+"@babel/plugin-transform-flow-strip-types@^7.4.0":
+  version "7.4.0"
+  resolved "https://registry.yarnpkg.com/@babel/plugin-transform-flow-strip-types/-/plugin-transform-flow-strip-types-7.4.0.tgz#f3c59eecff68c99b9c96eaafe4fe9d1fa8947138"
+  integrity sha512-C4ZVNejHnfB22vI2TYN4RUp2oCmq6cSEAg4RygSvYZUECRqUu9O4PMEMNJ4wsemaRGg27BbgYctG4BZh+AgIHw==
+  dependencies:
+    "@babel/helper-plugin-utils" "^7.0.0"
+    "@babel/plugin-syntax-flow" "^7.2.0"
+
 "@babel/plugin-transform-for-of@^7.0.0":
   version "7.0.0"
   resolved "https://registry.yarnpkg.com/@babel/plugin-transform-for-of/-/plugin-transform-for-of-7.0.0.tgz#f2ba4eadb83bd17dc3c7e9b30f4707365e1c3e39"
@@ -906,6 +914,14 @@
     js-levenshtein "^1.1.3"
     semver "^5.3.0"
 
+"@babel/preset-flow@^7.0.0-rc.1":
+  version "7.0.0"
+  resolved "https://registry.yarnpkg.com/@babel/preset-flow/-/preset-flow-7.0.0.tgz#afd764835d9535ec63d8c7d4caf1c06457263da2"
+  integrity sha512-bJOHrYOPqJZCkPVbG1Lot2r5OSsB+iUOaxiHdlOeB1yPWS6evswVHwvkDLZ54WTaTRIk89ds0iHmGZSnxlPejQ==
+  dependencies:
+    "@babel/helper-plugin-utils" "^7.0.0"
+    "@babel/plugin-transform-flow-strip-types" "^7.0.0"
+
 "@babel/[email protected]", "@babel/preset-react@^7.0.0":
   version "7.0.0"
   resolved "https://registry.yarnpkg.com/@babel/preset-react/-/preset-react-7.0.0.tgz#e86b4b3d99433c7b3e9e91747e2653958bc6b3c0"
@@ -5801,6 +5817,11 @@ flatten@^1.0.2:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/flatten/-/flatten-1.0.2.tgz#dae46a9d78fbe25292258cc1e780a41d95c03782"
 
+flow-bin@^0.96.0:
+  version "0.96.0"
+  resolved "https://registry.yarnpkg.com/flow-bin/-/flow-bin-0.96.0.tgz#3b0379d97304dc1879ae6db627cd2d6819998661"
+  integrity sha512-OSxERs0EdhVxEVCst/HmlT/RcnXsQQIRqcfK9J9wC8/93JQj+xQz4RtlsmYe1PSRYaozuDLyPS5pIA81Zwzaww==
+
 flush-write-stream@^1.0.0:
   version "1.0.3"
   resolved "https://registry.yarnpkg.com/flush-write-stream/-/flush-write-stream-1.0.3.tgz#c5d586ef38af6097650b49bc41b55fabb19f35bd"
@@ -6028,6 +6049,14 @@ gatsby-plugin-feed@^2.1.0:
     lodash.merge "^4.6.0"
     rss "^1.2.2"
 
+gatsby-plugin-flow@^1.0.4:
+  version "1.0.4"
+  resolved "https://registry.yarnpkg.com/gatsby-plugin-flow/-/gatsby-plugin-flow-1.0.4.tgz#13a93a734115fb595fc725c319c47a007841d94d"
+  integrity sha512-HUFDiZIBEU6ZM6gOytKdX0FtgpZyw3vycZwGdY4Y6rtins9iXrfNmnh0pMyb8jVmCWUlxSPu+LMt14sm1QVDOg==
+  dependencies:
+    "@babel/preset-flow" "^7.0.0-rc.1"
+    "@babel/runtime" "^7.0.0"
+
 gatsby-plugin-google-gtag@^1.0.16:
   version "1.0.16"
   resolved "https://registry.yarnpkg.com/gatsby-plugin-google-gtag/-/gatsby-plugin-google-gtag-1.0.16.tgz#547cd1302277e99fc7397dbf9d36d7e7a647657c"