test: add browser test for URI drop onto Vue nodes

Adds a Playwright test that drops a workflow URL onto a Vue node
element to verify the event bubbles to the document-level handler.

Also adds preserveNativePropagation option to DragDropHelper to
allow testing real event propagation behavior without overriding
stopPropagation.

browser_tests/fixtures/helpers/DragDropHelper.ts

@@ -24,13 +24,15 @@ export class DragDropHelper {
       url?: string
       dropPosition?: Position
       waitForUpload?: boolean
+      preserveNativePropagation?: boolean
     } = {}
   ): Promise<void> {
     const {
       dropPosition = { x: 100, y: 100 },
       fileName,
       url,
-      waitForUpload = false
+      waitForUpload = false,
+      preserveNativePropagation = false
     } = options
 
     if (!fileName && !url)
@@ -42,7 +44,8 @@ export class DragDropHelper {
       fileType?: string
       buffer?: Uint8Array | number[]
       url?: string
-    } = { dropPosition }
+      preserveNativePropagation: boolean
+    } = { dropPosition, preserveNativePropagation }
 
     if (fileName) {
       const filePath = this.assetPath(fileName)
@@ -125,15 +128,17 @@ export class DragDropHelper {
         )
       }
 
-      Object.defineProperty(dropEvent, 'preventDefault', {
-        value: () => {},
-        writable: false
-      })
+      if (!params.preserveNativePropagation) {
+        Object.defineProperty(dropEvent, 'preventDefault', {
+          value: () => {},
+          writable: false
+        })
 
-      Object.defineProperty(dropEvent, 'stopPropagation', {
-        value: () => {},
-        writable: false
-      })
+        Object.defineProperty(dropEvent, 'stopPropagation', {
+          value: () => {},
+          writable: false
+        })
+      }
 
       targetElement.dispatchEvent(dragOverEvent)
       targetElement.dispatchEvent(dropEvent)
@@ -164,7 +169,10 @@ export class DragDropHelper {
 
   async dragAndDropURL(
     url: string,
-    options: { dropPosition?: Position } = {}
+    options: {
+      dropPosition?: Position
+      preserveNativePropagation?: boolean
+    } = {}
   ): Promise<void> {
     return this.dragAndDropExternalResource({ url, ...options })
   }

browser_tests/tests/loadWorkflowInMedia.spec.ts

@@ -67,5 +67,37 @@ test.describe(
         )
       })
     })
+
+    test('Load workflow from URL dropped onto Vue node', async ({
+      comfyPage
+    }) => {
+      await comfyPage.settings.setSetting('Comfy.VueNodes.Enabled', true)
+      await comfyPage.vueNodes.waitForNodes()
+
+      const initialNodeCount = await comfyPage.nodeOps.getGraphNodesCount()
+
+      const node = comfyPage.vueNodes.getNodeByTitle('KSampler')
+      const box = await node.boundingBox()
+      expect(box).not.toBeNull()
+
+      const dropPosition = {
+        x: box!.x + box!.width / 2,
+        y: box!.y + box!.height / 2
+      }
+
+      await comfyPage.dragDrop.dragAndDropURL(
+        'https://comfyanonymous.github.io/ComfyUI_examples/hidream/hidream_dev_example.png',
+        { dropPosition, preserveNativePropagation: true }
+      )
+
+      await comfyPage.page.waitForFunction(
+        (prevCount) => window.app!.graph.nodes.length !== prevCount,
+        initialNodeCount,
+        { timeout: 10000 }
+      )
+
+      const newNodeCount = await comfyPage.nodeOps.getGraphNodesCount()
+      expect(newNodeCount).not.toBe(initialNodeCount)
+    })
   }
 )