validateNewlineAfterArrayElements: --fix now works for this rule

Fixes #2065
Closes gh-2072

Author: joerideg

lib/rules/validate-newline-after-array-elements.js

@@ -132,35 +132,58 @@ module.exports.prototype = {
 
         file.iterateNodesByType(['ArrayExpression'], function(node) {
             var els = node.elements;
+            var firstEl = els[0];
+            var lastEl = els[els.length - 1];
+            var bracket;
+            var elToken;
+
             if (els.length <= maximum && node.loc.start.line === node.loc.end.line) {
                 return;
             }
 
             if (!ignoreBrackets) {
-                if (els[0] && els[0].loc.start.line === node.loc.start.line) {
-                    errors.add('First element should be placed on new line', els[0].loc.start);
+                if (firstEl && firstEl.loc.start.line === node.loc.start.line) {
+                    bracket = file.getFirstNodeToken(node);
+                    elToken = file.getNextToken(bracket);
+
+                    errors.assert.differentLine({
+                        token: bracket,
+                        nextToken: elToken,
+                        message: 'First element should be placed on new line'
+                    });
                 }
-                if (els[els.length - 1] && els[els.length - 1].loc.end.line === node.loc.end.line) {
-                    errors.add('Closing bracket should be placed on new line', node.loc.end);
+                if (lastEl && lastEl.loc.end.line === node.loc.end.line) {
+                    bracket = file.getLastNodeToken(node);
+                    elToken = file.getPrevToken(bracket);
+
+                    errors.assert.differentLine({
+                        token: elToken,
+                        nextToken: bracket,
+                        message: 'Closing bracket should be placed on new line'
+                    });
                 }
             }
 
-            var prevLine = 0;
             els.forEach(function(elem) {
+                var elToken;
+                var comma;
+
                 if (!elem) {
                     // skip holes
                     return;
                 }
-                var line = elem.loc.start.line;
-                if (prevLine === line) {
-                    errors.add('Multiple elements at a single line in multiline array', {
-                        line: line,
-                        column: elem.loc.start.column
+
+                if (firstEl !== elem) {
+                    elToken = file.getFirstNodeToken(elem);
+                    comma = file.getPrevToken(elToken);
+
+                    errors.assert.differentLine({
+                        token: comma,
+                        nextToken: elToken,
+                        message: 'Multiple elements at a single line in multiline array'
                     });
                 }
-                prevLine = line;
             });
-
         });
     }
 };