feat(examples): enable examples to be formatted in YAML using command…

… line option `-f yaml`

When using the command line option `-f yaml` or `--example format yaml`, all examples will be
formatted as YAML instead of JSON

lib/index.js

@@ -87,6 +87,11 @@ async function main(args) {
     .choices('l', ['en_US', 'de'])
     .default('l', 'en_US')
 
+    .alias('f', 'example-format')
+    .describe('f', 'how to format examples')
+    .choices('f', ['json', 'yaml'])
+    .default('f', 'json')
+
     .alias('p', 'properties')
     .array('p')
     .describe('p', 'name of a custom property which should be also in the description of an element (may be used multiple times)')
@@ -161,6 +166,7 @@ async function main(args) {
       header: argv.h,
       links: docs,
       includeproperties: argv.p,
+      exampleformat: argv.f,
       rewritelinks: (origin) => {
         const mddir = argv.o;
         const srcdir = argv.d;

lib/markdownBuilder.js

@@ -19,12 +19,17 @@ const {
 } = require('mdast-builder');
 const i18n = require('es2015-i18n-tag').default;
 const ghslugger = require('github-slugger');
+const yaml = require('js-yaml');
 const s = require('./symbols');
 const { gentitle } = require('./formattingTools');
 const { keyword } = require('./keywords');
 
 function build({
-  header, links = {}, includeproperties = [], rewritelinks = x => x,
+  header,
+  links = {},
+  includeproperties = [],
+  rewritelinks = x => x,
+  exampleformat = 'json',
 } = {}) {
   const formats = {
     'date-time': {
@@ -656,7 +661,13 @@ function build({
 
 
   function makeexamples(schema, level = 1) {
-    if (schema[keyword`examples`] && schema[keyword`examples`].length > 0) {
+    if (schema[keyword`examples`] && schema[keyword`examples`].length > 0 && exampleformat === 'yaml') {
+      return [
+        heading(level + 1, text(i18n`${simpletitle(schema)} Examples`)),
+        ...schema[keyword`examples`].map(example => paragraph(code('yaml', yaml.safeDump(example, undefined, 2)))),
+      ];
+    }
+    if (schema[keyword`examples`] && schema[keyword`examples`].length > 0 && exampleformat === 'json') {
       return [
         heading(level + 1, text(i18n`${simpletitle(schema)} Examples`)),
         ...schema[keyword`examples`].map(example => paragraph(code('json', JSON.stringify(example, undefined, 2)))),