[Bug] Fix input link slots (#3349)

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browser_tests/assets/input_order_swap.json

@@ -0,0 +1,74 @@
+{
+  "id": "51b9b184-770d-40ac-a478-8cc31667ff23",
+  "revision": 0,
+  "last_node_id": 2,
+  "last_link_id": 1,
+  "nodes": [
+    {
+      "id": 1,
+      "type": "CLIPTextEncode",
+      "pos": [904, 466],
+      "size": [400, 200],
+      "flags": {},
+      "order": 1,
+      "mode": 0,
+      "inputs": [
+        {
+          "name": "text",
+          "type": "STRING",
+          "widget": {
+            "name": "text"
+          },
+          "link": 1
+        },
+        {
+          "name": "clip",
+          "type": "CLIP",
+          "link": null
+        }
+      ],
+      "outputs": [
+        {
+          "name": "CONDITIONING",
+          "type": "CONDITIONING",
+          "links": null
+        }
+      ],
+      "properties": {
+        "Node name for S&R": "CLIPTextEncode"
+      },
+      "widgets_values": [""]
+    },
+    {
+      "id": 2,
+      "type": "PrimitiveString",
+      "pos": [556.8589477539062, 472.94342041015625],
+      "size": [315, 58],
+      "flags": {},
+      "order": 0,
+      "mode": 0,
+      "inputs": [],
+      "outputs": [
+        {
+          "name": "STRING",
+          "type": "STRING",
+          "links": [1]
+        }
+      ],
+      "properties": {
+        "Node name for S&R": "PrimitiveString"
+      },
+      "widgets_values": ["foo"]
+    }
+  ],
+  "links": [[1, 2, 0, 1, 0, "STRING"]],
+  "groups": [],
+  "config": {},
+  "extra": {
+    "ds": {
+      "scale": 1.7715610000000013,
+      "offset": [-388.521484375, -162.31336975097656]
+    }
+  },
+  "version": 0.4
+}

browser_tests/tests/graph.spec.ts

@@ -0,0 +1,16 @@
+import { expect } from '@playwright/test'
+
+import { comfyPageFixture as test } from '../fixtures/ComfyPage'
+
+test.describe('Graph', () => {
+  // Should be able to fix link input slot index after swap the input order
+  // Ref: https://github.com/Comfy-Org/ComfyUI_frontend/issues/3348
+  test('Fix link input slots', async ({ comfyPage }) => {
+    await comfyPage.loadWorkflow('input_order_swap')
+    expect(
+      await comfyPage.page.evaluate(() => {
+        return window['app'].graph.links.get(1)?.target_slot
+      })
+    ).toBe(1)
+  })
+})