Throw exception if segments or curves of wrong paths are passed to smooth()

build/docs.sh

@@ -31,5 +31,5 @@ cd ..
 if [ $MODE = "docs" ]
 then
     # Build paper.js library for documentation
-    ./preprocess.sh stripped ../src/paper.js "-o '{ \"browser\": true }' -i '../src/constants.js'" ../dist/docs/assets/js/paper.js
+    ./preprocess.sh stripped ../src/paper.js "-i '../src/constants.js'" ../dist/docs/assets/js/paper.js
 fi

src/path/Path.js

@@ -2065,15 +2065,20 @@ var Path = PathItem.extend(/** @lends Path# */{
         // For numbers, the `to` index is exclusive, while for segments and
         // curves, it is inclusive, handled by the `offset` parameter.
         function getIndex(value, _default) {
-            var index = value == null
-                    ? _default
-                    : typeof value === 'number'
-                        ? value
-                        // Support both Segment and Curve through getIndex()
-                        : value.getIndex
-                            ? value.getIndex()
-                                + (_default && value instanceof Curve ? 1 : 0)
-                            : _default;
+            // Support both Segment and Curve through #index getter.
+            var index = value && value.index;
+            if (index != null) {
+                // Make sure the segment / curve is not from a wrong path.
+                var path = value.path;
+                if (path && path !== that)
+                    throw new Error(value._class + ' ' + index + ' of ' + path
+                            + ' is not part of ' + that);
+                // Add offset of 1 to curves to reach their end segment.
+                if (_default && value instanceof Curve)
+                    index++;
+            } else {
+                index = typeof value === 'number' ? value : _default;
+            }
             // Handle negative values based on whether a path is open or not:
             // Ranges on closed paths are allowed to wrapped around the
             // beginning/end (e.g. start near the end, end near the beginning),
@@ -2083,7 +2088,8 @@ var Path = PathItem.extend(/** @lends Path# */{
                     : index < 0 ? index + length : index, length - 1);
         }
 
-        var opts = options || {},
+        var that = this,
+            opts = options || {},
             type = opts.type || 'asymmetric',
             segments = this._segments,
             length = segments.length,

src/path/PathItem.js

@@ -409,7 +409,7 @@ var PathItem = Item.extend(/** @lends PathItem# */{
      * // Smooth the segments of the copy:
      * copy.smooth({ type: 'continuous' });
      *
-     * @example {@paperscript}
+     * @example {@paperscript height=220}
      * var path = new Path();
      * path.strokeColor = 'black';
      *
@@ -434,7 +434,7 @@ var PathItem = Item.extend(/** @lends PathItem# */{
      * // Smooth the path using centripetal Catmull-Rom splines:
      * copy.smooth({ type: 'catmull-rom', factor: 0.5 });
      *
-     * @example {@paperscript}
+     * @example {@paperscript height=110}
      * // Smoothing ranges of paths, using segments, curves or indices:
      *
      * // Create 5 rectangles, next to each other: