date filter formatting

src/filters/dateFilter.js

@@ -0,0 +1,36 @@
+/*
+Stolen from https://stackoverflow.com/a/31615643
+via https://github.com/andy-piccalilli/hylia
+*/
+const appendSuffix = (n) => {
+    var s = ['th', 'st', 'nd', 'rd'],
+        v = n % 100
+    return n + (s[(v - 20) % 10] || s[v] || s[0])
+}
+
+module.exports = function dateFilter(value) {
+    const dateObject = new Date(value)
+
+    const months = [
+        'January',
+        'February',
+        'March',
+        'April',
+        'May',
+        'June',
+        'July',
+        'August',
+        'September',
+        'October',
+        'November',
+        'December'
+    ]
+    // fixes off by one day error
+    let datePlusOne = dateObject.getDate() + 1
+
+    const dayWithSuffix = appendSuffix(dateObject.getDate())
+
+    return `${
+        months[dateObject.getMonth()]
+    } ${datePlusOne}, ${dateObject.getFullYear()}`
+}

src/filters/w3DateFilter.js

@@ -0,0 +1,4 @@
+module.exports = function w3cDate(value) {
+    const dateObject = new Date(value)
+    return dateObject.toISOString()
+}

src/includes/layouts/post.njk

@@ -1,9 +1,10 @@
 ---
 layout: base
 ---
-
+<p>&laquo; Back to posts</p>
 <article>
   <h2>{{ title }}</h2>
+  <time>{{ date | dateFilter }}</time>
   {{ content | safe }}
   {% for tag in tags %}
   {% set tagUrl %}/tags/{{ tag | slug }}/{% endset %}

src/includes/partials/posts-list.njk

@@ -6,8 +6,8 @@
                 {{ post.data.title }}
             </h2>
         </a>
-        <time>
-            {{ post.data.date }}
+        <time datetime="{{ post.data.date | w3Date }}">
+            {{ post.data.date | dateFilter }}
         </time>
         <p>
             {{ post.data.page.excerpt }}