Adding react-helmet and starting on a Layout component

gatsby-config.js

@@ -0,0 +1,5 @@
+module.exports = {
+  plugins: [
+    'gatsby-plugin-react-helmet'
+  ]
+};

package.json

@@ -19,8 +19,10 @@
     "eslint-plugin-import": "^2.14.0",
     "eslint-plugin-react": "^7.12.1",
     "gatsby": "^2.0.81",
+    "gatsby-plugin-react-helmet": "^3.0.5",
     "prop-types": "^15.6.2",
     "react": "^16.7.0",
-    "react-dom": "^16.7.0"
+    "react-dom": "^16.7.0",
+    "react-helmet": "^5.2.0"
   }
 }

src/components/Layout/index.js

@@ -0,0 +1,20 @@
+import React from 'react';
+import PropTypes from 'prop-types';
+import { Helmet } from 'react-helmet';
+
+const Layout = ({ title, children }) => <React.Fragment>
+  <Helmet>
+    <title>{ title ? `Regexper - ${ title }` : 'Regexper' }</title>
+  </Helmet>
+  { children }
+</React.Fragment>;
+
+Layout.propTypes = {
+  title: PropTypes.string,
+  children: PropTypes.oneOfType([
+    PropTypes.arrayOf(PropTypes.node),
+    PropTypes.node
+  ]).isRequired
+};
+
+export default Layout;

src/pages/index.js

@@ -1,5 +1,9 @@
 import React from 'react';
 
-const IndexPage = () => <div>Hello world</div>;
+import Layout from 'components/Layout';
+
+const IndexPage = () => <Layout>
+  <div>Hello world</div>
+</Layout>;
 
 export default IndexPage;

yarn.lock

@@ -4047,6 +4047,11 @@ execa@^1.0.0:
     signal-exit "^3.0.0"
     strip-eof "^1.0.0"
 
+exenv@^1.2.1:
+  version "1.2.2"
+  resolved "https://registry.yarnpkg.com/exenv/-/exenv-1.2.2.tgz#2ae78e85d9894158670b03d47bec1f03bd91bb9d"
+  integrity sha1-KueOhdmJQVhnCwPUe+wfA72Ru50=
+
 expand-brackets@^0.1.4:
   version "0.1.5"
   resolved "https://registry.yarnpkg.com/expand-brackets/-/expand-brackets-0.1.5.tgz#df07284e342a807cd733ac5af72411e581d1177b"
@@ -4594,6 +4599,13 @@ gatsby-plugin-page-creator@^2.0.5:
     parse-filepath "^1.0.1"
     slash "^1.0.0"
 
+gatsby-plugin-react-helmet@^3.0.5:
+  version "3.0.5"
+  resolved "https://registry.yarnpkg.com/gatsby-plugin-react-helmet/-/gatsby-plugin-react-helmet-3.0.5.tgz#eaeca7c83c6c273d31454598949dd0d3b4ff5f31"
+  integrity sha512-Xn8d4EckfUkO3xB8qfjn1AcqeA2fYgd6Mbin3RHc/Zu6YRiOQqdJAVBXz+7PbFpTt+6GCluKklEpFUA4RS4oYw==
+  dependencies:
+    "@babel/runtime" "^7.0.0"
+
 gatsby-react-router-scroll@^2.0.2:
   version "2.0.2"
   resolved "https://registry.yarnpkg.com/gatsby-react-router-scroll/-/gatsby-react-router-scroll-2.0.2.tgz#d8046ce2f3bfa52ef6ec55804007d976b0bb6bef"
@@ -7741,7 +7753,7 @@ promise@^7.1.1:
   dependencies:
     asap "~2.0.3"
 
-prop-types@^15.6.1, prop-types@^15.6.2:
+prop-types@^15.5.4, prop-types@^15.6.1, prop-types@^15.6.2:
   version "15.6.2"
   resolved "https://registry.yarnpkg.com/prop-types/-/prop-types-15.6.2.tgz#05d5ca77b4453e985d60fc7ff8c859094a497102"
   integrity sha512-3pboPvLiWD7dkI3qf3KbUe6hKFKa52w+AE0VCqECtf+QHAKgOL37tTaNCnuX1nAAQ4ZhyP+kYVKf8rLmJ/feDQ==
@@ -7942,6 +7954,16 @@ react-error-overlay@^3.0.0:
   resolved "https://registry.yarnpkg.com/react-error-overlay/-/react-error-overlay-3.0.0.tgz#c2bc8f4d91f1375b3dad6d75265d51cd5eeaf655"
   integrity sha512-XzgvowFrwDo6TWcpJ/WTiarb9UI6lhA4PMzS7n1joK3sHfBBBOQHUc0U4u57D6DWO9vHv6lVSWx2Q/Ymfyv4hw==
 
+react-helmet@^5.2.0:
+  version "5.2.0"
+  resolved "https://registry.yarnpkg.com/react-helmet/-/react-helmet-5.2.0.tgz#a81811df21313a6d55c5f058c4aeba5d6f3d97a7"
+  integrity sha1-qBgR3yExOm1VxfBYxK66XW89l6c=
+  dependencies:
+    deep-equal "^1.0.1"
+    object-assign "^4.1.1"
+    prop-types "^15.5.4"
+    react-side-effect "^1.1.0"
+
 react-hot-loader@^4.6.2:
   version "4.6.3"
   resolved "https://registry.yarnpkg.com/react-hot-loader/-/react-hot-loader-4.6.3.tgz#d9c8923c45b35fd51538ba4297081a00be6bccb1"
@@ -7962,6 +7984,14 @@ react-lifecycles-compat@^3.0.4:
   resolved "https://registry.yarnpkg.com/react-lifecycles-compat/-/react-lifecycles-compat-3.0.4.tgz#4f1a273afdfc8f3488a8c516bfda78f872352362"
   integrity sha512-fBASbA6LnOU9dOU2eW7aQ8xmYBSXUIWr+UmF9b1efZBazGNO+rcXT/icdKnYm2pTwcRylVUYwW7H1PHfLekVzA==
 
+react-side-effect@^1.1.0:
+  version "1.1.5"
+  resolved "https://registry.yarnpkg.com/react-side-effect/-/react-side-effect-1.1.5.tgz#f26059e50ed9c626d91d661b9f3c8bb38cd0ff2d"
+  integrity sha512-Z2ZJE4p/jIfvUpiUMRydEVpQRf2f8GMHczT6qLcARmX7QRb28JDBTpnM2g/i5y/p7ZDEXYGHWg0RbhikE+hJRw==
+  dependencies:
+    exenv "^1.2.1"
+    shallowequal "^1.0.1"
+
 react@^16.7.0:
   version "16.7.0"
   resolved "https://registry.yarnpkg.com/react/-/react-16.7.0.tgz#b674ec396b0a5715873b350446f7ea0802ab6381"
@@ -8575,7 +8605,7 @@ shallow-compare@^1.2.2:
   resolved "https://registry.yarnpkg.com/shallow-compare/-/shallow-compare-1.2.2.tgz#fa4794627bf455a47c4f56881d8a6132d581ffdb"
   integrity sha512-LUMFi+RppPlrHzbqmFnINTrazo0lPNwhcgzuAXVVcfy/mqPDrQmHAyz5bvV0gDAuRFrk804V0HpQ6u9sZ0tBeg==
 
-shallowequal@^1.0.2:
+shallowequal@^1.0.1, shallowequal@^1.0.2:
   version "1.1.0"
   resolved "https://registry.yarnpkg.com/shallowequal/-/shallowequal-1.1.0.tgz#188d521de95b9087404fd4dcb68b13df0ae4e7f8"
   integrity sha512-y0m1JoUZSlPAjXVtPPW70aZWfIL/dSP7AFkRnniLCrK/8MDKog3TySTBmckD+RObVxH0v4Tox67+F14PdED2oQ==