Merge pull request #5 from azu/fix_4

Add "json" formatter

lib/formatters/json.js

@@ -0,0 +1,5 @@
+// LICENSE : MIT
+"use strict";
+module.exports = function (results) {
+    return JSON.stringify(results);
+};

test/json-test.js

@@ -0,0 +1,47 @@
+// LICENSE : MIT
+"use strict";
+var assert = require("power-assert");
+describe("json-test", function () {
+    it("should return json", function () {
+
+        it("run all formatter", function () {
+            var formatter = createFormatter({
+                formatterName: "json"
+            });
+            var results = [
+                {
+                    filePath: __dirname + "/fixtures/myfile.js",
+                    messages: [
+                        {
+                            ruleId: "semi",
+                            line: 1,
+                            column: 0,
+                            message: "0 pattern."
+                        },
+                        {
+                            ruleId: "semi",
+                            line: 2,
+                            column: 26,
+                            message: "Expected a semicolon."
+                        },
+                        {
+                            ruleId: "semi",
+                            line: 1,
+                            column: 21,
+                            message: "Expected a semicolon."
+                        },
+                        {
+                            ruleId: "semi",
+                            line: 2,
+                            column: 26,
+                            message: "Expected a semicolon."
+                        }
+                    ]
+                }
+            ];
+            var output = formatter(results);
+            var reParse = JSON.parse(output);
+            assert.deepEqual(reParse, results);
+        });
+    });
+});