Line: follow the new dropTarget default in the tests and comments

Author: VTT-AI-Agent

client/js/editor/sidebar/properties.js

@@ -5590,8 +5590,8 @@ class PropertiesModule extends SidebarModule {
     };
 
     // the line takes widgets in like a holder does: the toggle switches its
-    // dropTarget between the default (the plain widgets stops usually are) and
-    // an empty list, which matches nothing. A more specific dropTarget can be
+    // dropTarget between the plain widgets stops usually are and the default
+    // empty list, which matches nothing. A more specific dropTarget can be
     // written in the property list below, the same way a holder's is.
     const takeDrops = addLineToggle('Drag widgets in to add stops', 'lineTakeDrops', 'Let a widget dragged onto the line become a stop of it - during play as well as in edit mode');
     this.addPropertyListener(widget, 'dropTarget', ()=>takeDrops.checked = asArray(widget.get('dropTarget')).filter(t=>t).length > 0);

client/js/widgets/line.js

@@ -34,7 +34,8 @@ export class Line extends Widget {
       // A line takes widgets in like a holder: what dropTarget matches becomes
       // a stop when it is dropped onto the path - during play as well as in
       // edit mode - and comes off the list again when it is dragged away. The
-      // default takes the plain widgets stops usually are, an empty list none.
+      // default empty list matches nothing, so a line takes drops only once it
+      // is given one - { type: null } for the plain widgets stops usually are.
       dropTarget: [],
 
       // properties applied to a widget when it enters / leaves the line

tests/client/line-widget.test.js

@@ -517,10 +517,12 @@ describe('dragging a widget onto a line to make it a stop', () => {
   let line, token;
 
   beforeEach(() => {
+    // a line takes nothing by default, so this one opts in with the dropTarget
+    // the editor's "Drag widgets in to add stops" toggle writes
     line = createLine({ id: 'drop-line', x: 100, y: 100, width: 200, height: 40, autoSpaceStops: false,
-      lineStart: { x: 0, y: 0 }, lineEnd: { x: 200, y: 0 } });
+      lineStart: { x: 0, y: 0 }, lineEnd: { x: 200, y: 0 }, dropTarget: { type: null } });
     token = new Widget('drop-token');
-    // a plain widget has no type, which is what the default dropTarget takes
+    // a plain widget has no type, which is what that dropTarget takes
     addWidget({ id: 'drop-token', x: 130, y: 80, width: 40, height: 40 }, token);
     token.coordGlobalFromCoordLocal = coord => ({ x: token.get('x') + coord.x, y: token.get('y') + coord.y });
     // the candidate lines are collected once when the drag starts
@@ -546,7 +548,9 @@ describe('dragging a widget onto a line to make it a stop', () => {
   });
 
   test('a line whose dropTarget matches nothing never takes a dropped widget', async () => {
-    await line.set('dropTarget', []);
+    // null is not storable, so this falls back to the default: an empty list
+    await line.set('dropTarget', null);
+    expect(line.get('dropTarget')).toEqual([]);
     expect(line.stopDropTarget(token, { x: 150, y: 100 })).toBeNull();
     expect(token.lineStopDropTarget()).toBeNull();
   });

tests/testcafe/editor.js

@@ -267,5 +267,5 @@ test('Line widget in edit mode', async t => {
     .click('#editorToolbar > div > [icon=delete_forever]');
   // the added stop's id is derived from the existing stops instead of being
   // random, so the compared state no longer depends on the seeded rand() stream
-  await compareState(t, '7da80b26d6a3d7352f9ae5d58dce6fab');
+  await compareState(t, 'a82be0977ae859e03f353c51aa947db9');
 });