add safeguard to circular references

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@f5io/jsonpath",
-  "version": "1.0.6",
+  "version": "1.0.7",
   "description": "Performant JSONPath implementation",
   "main": "lib/index.js",
   "scripts": {

src/utils/index.js

@@ -39,23 +39,27 @@ export const pathFilter = f => x => {
   return output;
 }
 
-export const searchFor = (o, p) => {
+export const searchFor = (o, p, visited = new Set()) => {
   let result = [];
+  if (visited.has(o)) return result;
+  visited.add(o);
   for (const k in o) {
     if (k === p) result = result.concat(o[k]);
     if (isPlainObject(o[k]) || Array.isArray(o[k]))
-      result = result.concat(searchFor(o[k], p));
+      result = result.concat(searchFor(o[k], p, visited));
   }
   return result;
 }
 
-export const searchForPath = (o, p, ps = []) => {
+export const searchForPath = (o, p, ps = [], visited = new Set()) => {
   let result = [];
+  if (visited.has(o)) return result;
+  visited.add(o);
   const coerce = Array.isArray(o) ? Number : x => x;
   for (const k in o) {
     if (k === p) result = result.concat([ ps.concat(coerce(k)) ]);
     if (isPlainObject(o[k]) || Array.isArray(o[k]))
-      result = result.concat(searchForPath(o[k], p, ps.concat(coerce(k))));
+      result = result.concat(searchForPath(o[k], p, ps.concat(coerce(k)), visited));
   }
   return result;
 }

test/index.js

@@ -3,7 +3,7 @@ import query, { paths } from '../src';
 import tokenizer from '../src/tokenizer';
 import parser from '../src/parser';
 import maybe from '../src/maybe';
-import { isPlainObject, isObject, searchForPath } from '../src/utils';
+import { isPlainObject, isObject } from '../src/utils';
 
 const data = require('./data.json');
 
@@ -31,7 +31,7 @@ const runQueries = (test, queries, expected, d = data) => {
 const runPaths = (test, queries, expected, d = data) => {
   queries.forEach(q => {
     const result = measure(`paths: '${q}'`, paths, q, d);
-    test.deepEquals(result, expected, `'${q}' should return expected paths`); 
+    test.deepEquals(result, expected, `'${q}' should return expected paths`);
   });
 };
 
@@ -69,15 +69,15 @@ test('isPlainObject - constructor not a function', t => {
 
 test('isPlainObject - constructor null prototype', t => {
   t.plan(1);
-  function f() {};
+  function f() {}
   f.prototype = null;
   const obj = { constructor: f };
   t.notOk(isPlainObject(obj), 'should return false');
 });
 
 test('isPlainObject - constructor no isPrototypeOf', t => {
   t.plan(1);
-  function f() {};
+  function f() {}
   delete f.prototype.isPrototypeOf;
   const obj = { constructor: f };
   t.notOk(isPlainObject(obj), 'should return false');
@@ -136,7 +136,7 @@ test('simple prop with no prev', t => {
   const expected = data.store;
   const queries = [
     'store'
-  ]
+  ];
   const paths = [ [ 'store' ] ];
   runQueries(t, queries, expected);
   runPaths(t, queries, paths);
@@ -300,7 +300,7 @@ test('get specific author', t => {
   ];
   const paths = [
     [ 'store', 'book', 0, 'author' ]
-  ]
+  ];
   runQueries(t, queries, expected);
   runPaths(t, queries, paths);
   t.end();
@@ -410,6 +410,29 @@ test('get authors with omember', t => {
   t.end();
 });
 
+test('circular reference guard', t => {
+  const foo = {
+    a: 1,
+  };
+  const bar = {
+    b: 2,
+    foo,
+  };
+  foo.bar = bar;
+  const data = {
+    bar,
+    foo,
+  };
+
+  const expected = [ bar.b ];
+  const path = [ [ 'bar', 'b' ] ];
+  t.doesNotThrow(() => query('$..b', data), 'should not throw a stack size exceeded');
+  t.deepEquals(query('$..b', data), expected, 'should return expected results');
+  t.doesNotThrow(() => paths('$..b', data), 'should not throw stack size exceeded');
+  t.deepEquals(paths('$..b', data), path, 'should return expected results');
+  t.end();
+});
+
 test('changejs example', t => {
   const expected = [
     [ 1, 2, 3 ], [ 4, 5, 6 ],