Use an options argument instead of various arguments, for ancestorsToArray()

Author: Joris-van-der-Wel

lib/SymbolTree.js

@@ -291,21 +291,18 @@ class SymbolTree {
          * @method ancestorsToArray
          * @memberOf module:symbol-tree#
          * @param {Object} object
-         * @param {Object[]} [array=[]]
-         * @param {Function} [filter] Function to test each object before it is added to the array.
+         * @param {Object} [options]
+         * @param {Object[]} [options.array=[]]
+         * @param {Function} [options.filter] Function to test each object before it is added to the array.
          *                            Invoked with arguments (object). Should return `true` if an object
          *                            is to be included.
-         * @param {*} [thisArg] Value to use as `this` when executing `filter`.
+         * @param {*} [options.thisArg] Value to use as `this` when executing `filter`.
          * @return {Object[]}
          */
-        ancestorsToArray(object, array, filter, thisArg) {
-                if (!array) {
-                        array = [];
-                }
-
-                if (!filter) {
-                        filter = returnTrue;
-                }
+        ancestorsToArray(object, options) {
+                const array   = (options && options.array  ) || [];
+                const filter  = (options && options.filter ) || returnTrue;
+                const thisArg = (options && options.thisArg) || undefined;
 
                 let ancestor = object;
 

test/SymbolTree.js

@@ -828,7 +828,7 @@ test('ancestorsToArray', function(t) {
         t.deepEqual([b], tree.ancestorsToArray(b));
 
         const arr = ['a', 5];
-        tree.ancestorsToArray(abaa, arr);
+        tree.ancestorsToArray(abaa, {array: arr});
         t.deepEqual(['a', 5, abaa, aba, ab, a], arr);
 
         t.end();
@@ -856,7 +856,7 @@ test('ancestorsToArray with filter', function(t) {
                 return object !== abaa && object !== ab;
         };
 
-        t.deepEqual([aba, a], tree.ancestorsToArray(abaa, null, filter, thisArg));
+        t.deepEqual([aba, a], tree.ancestorsToArray(abaa, {filter: filter, thisArg: thisArg}));
 
         t.end();
 });