#349: Use js-yaml to parse json, yaml, and yml config files

Author: Brandon Morrison

core/lib/patternlab.js

@@ -10,7 +10,7 @@
 
 "use strict";
 
-var diveSync = require('diveSync'),
+const diveSync = require('diveSync'),
   glob = require('glob'),
   _ = require('lodash'),
   path = require('path'),
@@ -35,16 +35,25 @@ console.log(
   chalk.bold(']====\n')
 );
 
-var patternEngines = require('./pattern_engines');
-var EventEmitter = require('events').EventEmitter;
+const patternEngines = require('./pattern_engines');
+const EventEmitter = require('events').EventEmitter;
 
+const yaml = require('js-yaml');
+
+/**
+ * Given a path, load info from the folder to compile into a single config object.
+ * @param dataFilesPath
+ * @param fsDep
+ * @returns {{}}
+ */
 function buildPatternData(dataFilesPath, fsDep) {
-  var dataFiles = glob.sync(dataFilesPath + '*.json', {"ignore" : [dataFilesPath + 'listitems.json']});
-  var mergeObject = {};
+  let dataFiles = glob.sync(dataFilesPath + '*.{json,yml,yaml}', {"ignore" : [dataFilesPath + 'listitems.{json,yml,yaml}']});
+  let mergeObject = {};
   dataFiles.forEach(function (filePath) {
-    var jsonData = fsDep.readJSONSync(path.resolve(filePath), 'utf8');
+    let jsonData = yaml.safeLoad(fsDep.readFileSync(path.resolve(filePath), 'utf8'));
     mergeObject = _.merge(mergeObject, jsonData);
   });
+
   return mergeObject;
 }
 
@@ -492,9 +501,15 @@ var patternlab_engine = function (config) {
       patternlab.data = {};
     }
     try {
-      patternlab.listitems = fs.readJSONSync(path.resolve(paths.source.data, 'listitems.json'));
+      let dataFiles = glob.sync(paths.source.data + 'listitems.{json,yml,yaml}');
+      let mergeObject = {};
+      dataFiles.forEach(function (filePath) {
+        let jsonData = yaml.safeLoad(fs.readFileSync(path.resolve(filePath), 'utf8'));
+        mergeObject = _.merge(mergeObject, jsonData);
+      });
+      patternlab.listitems = mergeObject;
     } catch (ex) {
-      plutils.warning('WARNING: missing or malformed ' + paths.source.data + 'listitems.json file.  Pattern Lab may not work without this file.');
+      plutils.warning('WARNING: missing or malformed ' + paths.source.data + 'listitems file.  Pattern Lab may not work without this file.');
       patternlab.listitems = {};
     }
     try {

test/files/_data/data.json

@@ -1,2 +1,2 @@
-{ "data" : "test" }
+{ "data" : "test", "from_json" : "from_json" }
 

test/files/_data/data.yaml

@@ -0,0 +1 @@
+from_yaml: "from_yaml"

test/files/_data/data.yml

@@ -0,0 +1 @@
+from_yml: "from_yml"

test/patternlab_tests.js

@@ -1,15 +1,27 @@
 'use strict';
 
-var tap = require('tap');
+const tap = require('tap');
 
 tap.test('buildPatternData - should merge all JSON files in the data folder except listitems', function(test){
-  var fs = require('fs-extra');
-        var plMain = require('../core/lib/patternlab');
-  var data_dir = './test/files/_data/';
+  const fs = require('fs-extra'),
+    plMain = require('../core/lib/patternlab'),
+    data_dir = './test/files/_data/';
 
-  var dataResult = plMain.build_pattern_data(data_dir, fs);
+  let dataResult = plMain.build_pattern_data(data_dir, fs);
   test.equals(dataResult.data, "test");
   test.equals(dataResult.foo, "bar");
   test.equals(dataResult.test_list_item, undefined);
   test.end();
 });
+
+tap.test('buildPatternData - can load json, yaml, and yml files', function(test) {
+  const fs = require('fs-extra'),
+    plMain = require('../core/lib/patternlab'),
+    data_dir = './test/files/_data/';
+
+  let dataResult = plMain.build_pattern_data(data_dir, fs);
+  test.equals(dataResult.from_yml, "from_yml");
+  test.equals(dataResult.from_yaml, "from_yaml");
+  test.equals(dataResult.from_json, "from_json");
+  test.end();
+});