Add JSON formatter

src/formatters/json.js

@@ -0,0 +1,46 @@
+/* global JSON */
+
+CSSLint.addFormatter({
+    //format information
+    id: "json",
+    name: "CSSLint JSON format",
+    json: [],
+
+    /**
+     * Return content to be printed before all file results.
+     * @return {String} to prepend before all results
+     */
+    startFormat: function() {
+        "use strict";
+        return "";
+    },
+
+    /**
+     * Return full JSON
+     * @return {String} to append after all results
+     */
+    endFormat: function() {
+        "use strict";
+        return JSON.stringify(this.json);
+    },
+
+    /**
+     * Given CSS Lint results for a file, return output for this format.
+     * @param results {Object} with error and warning messages
+     * @param filename {String} relative file path
+     * @param options {Object} (UNUSED for now) specifies special handling of output
+     * @return {String} output for results
+     */
+    formatResults: function(results, filename, options) {
+        "use strict";
+        options = options || {};
+
+        if (results.messages.length > 0) {
+            this.json.push({
+                filename: filename,
+                results: results
+            });
+        }
+        return "";
+    }
+});

tests/formatters/json.js

@@ -0,0 +1,54 @@
+(function() {
+    "use strict";
+    var Assert = YUITest.Assert;
+
+    YUITest.TestRunner.add(new YUITest.TestCase({
+
+        name: "JSON formatter",
+
+        "File with no problems should return empty string": function() {
+            var result = {
+                    messages: [],
+                    stats: []
+                },
+                actual = CSSLint.getFormatter("json").formatResults(result, "path/to/FILE", {
+                    fullPath: "/absolute/path/to/FILE"
+                });
+            Assert.areEqual("", actual);
+        },
+
+        "Files with problems should list them": function() {
+            var result = {
+                messages: [{
+                    type: "warning",
+                    line: 1,
+                    col: 1,
+                    message: "BOGUS",
+                    evidence: "ALSO BOGUS",
+                    rule: []
+                }, {
+                    type: "error",
+                    line: 2,
+                    col: 1,
+                    message: "BOGUS",
+                    evidence: "ALSO BOGUS",
+                    rule: []
+                }],
+                stats: []
+            };
+
+            /*jshint -W108 */
+            var expected = '[{"filename":"path/to/FILE","results":{"messages":[{"type":"warning","line":1,"col":1,"message":"BOGUS","evidence":"ALSO BOGUS","rule":[]},{"type":"error","line":2,"col":1,"message":"BOGUS","evidence":"ALSO BOGUS","rule":[]}],"stats":[]}}]';
+
+            var formatter = CSSLint.getFormatter("json");
+
+            var actual = formatter.startFormat() + formatter.formatResults(result, "path/to/FILE", {
+                fullPath: "/absolute/path/to/FILE"
+            }) + formatter.endFormat();
+
+            Assert.areEqual(expected, actual);
+        }
+
+    }));
+
+})();