- Fix: Allow empty string keys

- Testing: Improve coverage

Author: brettz9

CHANGES.md

@@ -6,6 +6,7 @@
 - Fix: Require `json` as "own" property
 - Fix: wrap: false returning inconsistent data types (@CacheControl)
 - Fix: Ensure throwing with a bad result type
+- Fix: Allow empty string keys
 - Fix: Avoid erring when value before parent selector is falsey
 - Fix: If `resultType` is "all", if path resolves internally to a
     non-array (string), ensure it is converted to an array before

src/jsonpath.js

@@ -594,7 +594,9 @@ JSONPath.prototype._trace = function (
             ));
         }
     // simple case--directly follow property
-    } else if (!literalPriority && val && hasOwnProp.call(val, loc)) {
+    } else if (
+        !literalPriority && (val || val === '') && hasOwnProp.call(val, loc)
+    ) {
         addRet(
             this._trace(x, val[loc], push(path, loc), val, loc, callback,
                 hasArrExpr, true)

test/test.parent-selector.js

@@ -35,16 +35,28 @@ checkBuiltInVMAndNodeVM(function (vmType, setBuiltInState) {
             assert.deepEqual(result, expected);
         });
 
+        // Todo: Handle "this._trace(...).filter is not a function" error`
         /*
-        // Todo: Handle Maximum call stack error getting here
-        it('parent root', () => {
-            const jsonSimple = {};
-            const expected = json.children;
-            const result = jsonpath({json: jsonSimple, path: '^', flatten: true});
+        it.only('parent root', () => {
+            const jsonSimple = {
+                children: null
+            };
+            const expected = jsonSimple.children;
+            const result = jsonpath({json: jsonSimple, path: '$^', flatten: true});
+            console.log('result', result);
             assert.deepEqual(result, expected);
         });
         */
 
+        it('empty string key (parent of)', () => {
+            const jsonSimple = {
+                '': null
+            };
+            const expected = jsonSimple;
+            const result = jsonpath({json: jsonSimple, path: '^', wrap: false});
+            assert.deepEqual(result, expected);
+        });
+
         it('no such parent', () => {
             const result = jsonpath({json, path: 'name^^'});
             assert.deepEqual(result, []);