Report full rule chain in recursive rule errors

The idea came from a PR by @Mingun:

  https://github.com/pegjs/pegjs/pull/307

lib/compiler/passes/report-left-recursion.js

@@ -37,8 +37,12 @@ function reportLeftRecursion(ast) {
 
     rule_ref: function(node) {
       if (arrays.contains(visitedRules, node.name)) {
+        visitedRules.push(node.name);
+
         throw new GrammarError(
-          "Possible left recursion detected for rule \"" + node.name + "\".",
+          "Possible left recursion detected ("
+            + visitedRules.join(" -> ")
+            + ").",
           node.location
         );
       }

spec/unit/compiler/passes/report-left-recursion.spec.js

@@ -8,7 +8,7 @@ describe("compiler pass |reportLeftRecursion|", function() {
 
   it("reports direct left recursion", function() {
     expect(pass).toReportError('start = start', {
-      message:  'Possible left recursion detected for rule \"start\".',
+      message:  'Possible left recursion detected (start -> start).',
       location: {
         start: { offset:  8, line: 1, column:  9 },
         end:   { offset: 13, line: 1, column: 14 }
@@ -21,7 +21,7 @@ describe("compiler pass |reportLeftRecursion|", function() {
       'start = stop',
       'stop  = start'
     ].join("\n"), {
-      message:  'Possible left recursion detected for rule \"start\".',
+      message:  'Possible left recursion detected (start -> stop -> start).',
       location: {
         start: { offset: 21, line: 2, column:  9 },
         end:   { offset: 26, line: 2, column: 14 }