added json format

__fixtures__/expected.json

@@ -0,0 +1 @@
+[{"name":"common","value":[{"name":"follow","stage":"added","value":false},{"name":"setting1","stage":"unchanged","value":"Value 1"},{"name":"setting2","stage":"removed","value":200},{"name":"setting3","stage":"updated","value":{"removed":true,"added":null}},{"name":"setting4","stage":"added","value":"blah blah"},{"name":"setting5","stage":"added","value":{"key5":"value5"}},{"name":"setting6","value":[{"name":"doge","value":[{"name":"wow","stage":"updated","value":{"removed":"","added":"so much"}}],"stage":"nested"},{"name":"key","stage":"unchanged","value":"value"},{"name":"ops","stage":"added","value":"vops"}],"stage":"nested"}],"stage":"nested"},{"name":"group1","value":[{"name":"baz","stage":"updated","value":{"removed":"bas","added":"bars"}},{"name":"foo","stage":"unchanged","value":"bar"},{"name":"nest","stage":"updated","value":{"removed":{"key":"value"},"added":"str"}}],"stage":"nested"},{"name":"group2","stage":"removed","value":{"abc":12345,"deep":{"id":45}}},{"name":"group3","stage":"added","value":{"deep":{"id":{"number":45}},"fee":100500}}]

__tests__/index.test.js

@@ -14,10 +14,12 @@ const json1 = getFixturePath('file1.json');
 const json2 = getFixturePath('file2.json');
 const expectedStylish = readFileSync(getFixturePath('expected.stylish.txt'), 'utf8');
 const expectedPlain = readFileSync(getFixturePath('expected.plain.txt'), 'utf8');
+const expectedJson = readFileSync(getFixturePath('expected.json'), 'utf8');
 test.each([
   [yaml1, yaml2, 'stylish', expectedStylish],
   [json1, json2, 'stylish', expectedStylish],
   [json1, yaml2, 'plain', expectedPlain],
+  [json1, json2, 'json', expectedJson],
 ])('should work', (file1, file2, format, expected) => {
   expect(genDiff(file1, file2, format)).toEqual(expected);
 });

formatters/index.js

@@ -1,3 +1,4 @@
+import json from './json.js';
 import plain from './plain.js';
 import stylish from './stylish.js';
 
@@ -8,6 +9,9 @@ const chooseFormat = (data, format) => {
   if (format === 'plain') {
     return plain(data);
   }
+  if (format === 'json') {
+    return json(data);
+  }
   return 'Unknown format';
 };
 export default chooseFormat;

formatters/json.js

@@ -0,0 +1 @@
+export default (tree) => JSON.stringify(tree);

src/index.js

@@ -44,6 +44,7 @@ const gendiff = (file1, file2) => {
   };
   return diff(file1, file2);
 };
+
 export default (filepath1, filepath2, format = 'stylish') => {
   const extname1 = path.extname(filepath1);
   const extname2 = path.extname(filepath2);