unit test and fix for flatten

- expand still broken

Fixes: IBM-Cloud#18

lib/flatten.js

@@ -29,7 +29,10 @@ module.exports.flatten = function flatten(obj, opts) {
   return jsonpath
     .nodes(obj, '$..*')
     .reduce((p,v) => {
-      if ( !opts.flattenAll && typeof v.value === 'string' && v.path.length === 2) {
+      if ( !opts.flattenAll &&
+        typeof v.value === 'string' &&
+        v.path.length === 2 &&
+        v.path[1].substring(0,2) !== '$.') {
         // It is a simple {key: "value"} … do not modify it
         p[v.path[1]] = v.value;
       } else if ( typeof v.value !== 'object') {

test/resfiltertest.js

@@ -0,0 +1,39 @@
+/*
+ * Copyright IBM Corp. 2015,2018
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+const expect = require('chai').expect;
+const flatten = require('../');
+const dataInput = require('./gp-res-filter.d/input.json');
+const dataOutput = require('./gp-res-filter.d/output.json');
+const expectOutput = dataOutput.reduce((p, v) => {
+  const {key,value} = v;
+  p[key] = value;
+  return p;
+}, {});
+
+describe('test vs. gp-res-filter files', function() {
+  it('should be able to flatten gp-res-filter/input.json', function() {
+    const input  = dataInput;
+    const output = flatten.flatten(input);
+    expect(output).to.deep.equal(expectOutput);
+  });
+  it('should be able to expand gp-res-filter/input.json', function() {
+    const input  = expectOutput;
+    const output = flatten.expand(input);
+    expect(output).to.deep.equal(dataInput);
+  });
+});
+