Prevent Item#importJSON() from overriding Item#insert()

Closes #1392

CHANGELOG.md

@@ -10,6 +10,7 @@
 
 - SVG Export: Fix error when `Item#matrix` is not invertible (#1580).
 - SVG Import: Fix gradient default values (#1632).
+- JSON Import: Prevent overriding `Item#insert()` (#1392).
 
 # `0.12.1`
 

src/core/Base.js

@@ -558,8 +558,16 @@ statics: /** @lends Base */{
                     if (args.length === 1 && obj instanceof Item
                             && (useTarget || !(obj instanceof Layer))) {
                         var arg = args[0];
-                        if (Base.isPlainObject(arg))
+                        if (Base.isPlainObject(arg)) {
                             arg.insert = false;
+                            // When using target, make sure the `item.insert()`
+                            // method is not overridden with the `arg.insert`
+                            // property that was just set. Pass an exclude
+                            // object to the call of `obj.set()` below (#1392).
+                            if (useTarget) {
+                                args = args.concat([{ insert: true }])
+                            }
+                        }
                     }
                     // When reusing an object, initialize it through #set()
                     // instead of the constructor function:

test/tests/JSON.js

@@ -256,3 +256,10 @@ test('Path#importJSON()', function() {
     equals(function() { return layer.firstChild === path; }, true);
     equals(function() { return path.parent === layer; }, true);
 });
+
+test('Item#importJSON() does not override Item#insert()', function() {
+    var path = new Path();
+    equals(typeof path.insert, 'function');
+    path.importJSON(path.exportJSON());
+    equals(typeof path.insert, 'function');
+});