Fix render issues after moving floating input links (#841)

- Fixes floating inputs have invisible segment after moving
- Fixes floating input can be moved onto existing input link, resulting
in the slot having two links

src/canvas/FloatingRenderLink.ts

@@ -96,12 +96,12 @@ export class FloatingRenderLink implements RenderLink {
     this.fromPos = fromReroute.pos
   }
 
-  canConnectToInput(): true {
-    return true
+  canConnectToInput(): boolean {
+    return this.toType === "input"
   }
 
-  canConnectToOutput(): true {
-    return true
+  canConnectToOutput(): boolean {
+    return this.toType === "output"
   }
 
   canConnectToReroute(reroute: Reroute): boolean {
@@ -118,6 +118,8 @@ export class FloatingRenderLink implements RenderLink {
     floatingLink.target_id = node.id
     floatingLink.target_slot = node.inputs.indexOf(input)
 
+    node.disconnectInput(node.inputs.indexOf(input))
+
     this.fromSlot._floatingLinks?.delete(floatingLink)
     input._floatingLinks ??= new Set()
     input._floatingLinks.add(floatingLink)

src/canvas/LinkConnector.ts

@@ -622,6 +622,7 @@ export class LinkConnector {
 
     for (const link of outputLinks) delete link._dragging
     for (const link of inputLinks) delete link._dragging
+    for (const link of floatingLinks) delete link._dragging
     for (const reroute of hiddenReroutes) delete reroute._dragging
 
     renderLinks.length = 0

test/LinkConnector.integration.test.ts

@@ -530,6 +530,27 @@ describe("LinkConnector Integration", () => {
 
       validateIntegrityFloatingRemoved()
     })
+
+    test("Dropping a floating input link onto input slot disconnects the existing link", ({ graph, connector }) => {
+      const manyOutputsNode = graph.getNodeById(4)!
+      manyOutputsNode.disconnectOutput(0)
+
+      const floatingInputNode = graph.getNodeById(6)!
+      const fromFloatingInput = floatingInputNode.inputs[0]
+
+      const hasInputNode = graph.getNodeById(2)!
+      const toInput = hasInputNode.inputs[0]
+
+      connector.moveInputLink(graph, fromFloatingInput)
+      const dropEvent = mockedInputDropEvent(hasInputNode, 0)
+      connector.dropLinks(graph, dropEvent)
+
+      expect(fromFloatingInput.link).toBeNull()
+      expect(fromFloatingInput._floatingLinks?.size).toBe(0)
+
+      expect(toInput.link).toBeNull()
+      expect(toInput._floatingLinks?.size).toBe(1)
+    })
   })
 
   test("Should drop floating links when both sides are disconnected", ({ graph, connector, reroutesBeforeTest, validateIntegrityNoChanges }) => {