Add prettyBytes snippet

snippets/prettyBytes.md

@@ -0,0 +1,55 @@
+### prettyBytes
+
+Converts a number in bytes to a human-readable string.
+
+Use an array dictionary of units to be accessed based on the exponent. Return the prettified
+string by building it up taking into account whether the supplied options and whether it is
+negative or not.
+
+```js
+const prettyBytes = (num, options) => {
+  options = { precision: 3, addSpace: true, wholeWord: false, ...options };
+  const UNITS = [
+    ['B', 'Byte'],
+    ['KB', 'Kilo'],
+    ['MB', 'Mega'],
+    ['GB', 'Giga'],
+    ['TB', 'Tera'],
+    ['PB', 'Peta'],
+    ['EB', 'Exa'],
+    ['ZB', 'Zetta'],
+    ['YB', 'Yotta']
+  ];
+  if (num < 0) num = -num;
+  if (num < 1) return (num < 0 ? '-' : '') + num + ' B';
+  const exponent = Math.min(Math.floor(Math.log10(num) / 3), UNITS.length - 1);
+  const n = Number(
+    (num / Math.pow(1000, exponent)).toPrecision(options.precision)
+  );
+  return (
+    (num < 0 ? '-' : '') +
+    n +
+    (options.addSpace ? ' ' : '') +
+    UNITS[exponent][options.wholeWord ? 1 : 0] +
+    (options.wholeWord && exponent > 0 ? 'byte' : '') +
+    (options.wholeWord && n !== 1 ? 's' : '')
+  );
+};
+```
+
+```js
+/*
+Default options: {
+  precision: 3, // number of digits
+  addSpace: true, // add a space between the unit and number?
+  wholeWord: false // use the whole word or two letters?
+}
+*/
+prettyBytes(1000); // 1 KB
+prettyBytes(123456789); // 123 MB
+prettyBytes(-50); // -50 B
+prettyBytes(27145424323.5821); // 27.1 GB
+prettyBytes(27145424323.5821, { precision: 5 }); // 27.145 GB
+prettyBytes(5500, { wholeWord: true }); // 5.5 Kilobytes
+prettyBytes(5500, { addSpace: false }); // 5.5KB
+```