Make Id types mutually incompatible

browser_tests/fixtures/VueNodeHelpers.ts

@@ -3,6 +3,8 @@
  */
 import type { Locator, Page } from '@playwright/test'
 
+import type { NodeId } from '@/lib/litegraph/src/LGraphNode'
+
 export class VueNodeHelpers {
   constructor(private page: Page) {}
 
@@ -39,7 +41,7 @@ export class VueNodeHelpers {
   /**
    * Get all Vue node IDs currently in the DOM
    */
-  async getNodeIds(): Promise<string[]> {
+  async getNodeIds(): Promise<NodeId[]> {
     return await this.nodes.evaluateAll((nodes) =>
       nodes
         .map((n) => n.getAttribute('data-node-id'))
@@ -50,14 +52,14 @@ export class VueNodeHelpers {
   /**
    * Select a specific Vue node by ID
    */
-  async selectNode(nodeId: string): Promise<void> {
+  async selectNode(nodeId: nodeId): Promise<void> {
     await this.page.locator(`[data-node-id="${nodeId}"]`).click()
   }
 
   /**
    * Select multiple Vue nodes by IDs using Ctrl+click
    */
-  async selectNodes(nodeIds: string[]): Promise<void> {
+  async selectNodes(nodeIds: NodeId[]): Promise<void> {
     if (nodeIds.length === 0) return
 
     // Select first node normally

browser_tests/tests/chatHistory.spec.ts

@@ -1,6 +1,8 @@
 import type { Page } from '@playwright/test'
 import { expect } from '@playwright/test'
 
+import type { NodeId } from '@/lib/litegraph/src/LGraphNode'
+
 import { comfyPageFixture as test } from '../fixtures/ComfyPage'
 
 interface ChatHistoryEntry {
@@ -33,7 +35,7 @@ async function renderChatHistory(page: Page, history: ChatHistoryEntry[]) {
 }
 
 test.describe('Chat History Widget', () => {
-  let nodeId: string
+  let nodeId: NodeId
 
   test.beforeEach(async ({ comfyPage }) => {
     nodeId = await renderChatHistory(comfyPage.page, [

src/lib/litegraph/src/LGraph.ts

@@ -574,7 +574,7 @@ export class LGraph
     const S: LGraphNode[] = []
     const M: Dictionary<LGraphNode> = {}
     // to avoid repeating links
-    const visited_links: Record<NodeId, boolean> = {}
+    const visited_links: Record<LinkId, boolean> = {}
     const remaining_links: Record<NodeId, number> = {}
 
     // search for the nodes without inputs (starting nodes)

src/lib/litegraph/src/LGraphCanvas.ts

@@ -6168,14 +6168,14 @@ export class LGraphCanvas
 
         case 'Delete': {
           // segment can be a Reroute object, in which case segment.id is the reroute id
-          const linkId =
-            segment instanceof Reroute
-              ? segment.linkIds.values().next().value
-              : segment.id
-          if (linkId !== undefined) {
-            graph.removeLink(linkId)
-            // Clean up layout store
-            layoutStore.deleteLinkLayout(linkId)
+          const linkIds =
+            segment instanceof Reroute ? segment.linkIds : [segment.id]
+          for (const linkId of linkIds) {
+            if (linkId !== undefined) {
+              graph.removeLink(linkId)
+              // Clean up layout store
+              layoutStore.deleteLinkLayout(linkId)
+            }
           }
           break
         }

src/lib/litegraph/src/LGraphNode.ts

@@ -40,7 +40,8 @@ import type {
   ReadOnlyPoint,
   ReadOnlyRect,
   Rect,
-  Size
+  Size,
+  UniqueId
 } from './interfaces'
 import {
   type LGraphNodeConstructor,
@@ -90,7 +91,7 @@ import { type WidgetTypeMap, toConcreteWidget } from './widgets/widgetMap'
 
 // #region Types
 
-export type NodeId = number | string
+export type NodeId = UniqueId<number | string, 'NodeId'>
 
 export type NodeProperty = string | number | boolean | object
 

src/lib/litegraph/src/LLink.ts

@@ -9,12 +9,14 @@ import type { LGraphNode, NodeId } from './LGraphNode'
 import type { Reroute, RerouteId } from './Reroute'
 import type {
   CanvasColour,
+  ILinkSegment,
   INodeInputSlot,
   INodeOutputSlot,
   ISlotType,
   LinkNetwork,
   LinkSegment,
-  ReadonlyLinkNetwork
+  ReadonlyLinkNetwork,
+  UniqueId
 } from './interfaces'
 import type {
   Serialisable,
@@ -24,7 +26,7 @@ import type {
 
 const layoutMutations = useLayoutMutations()
 
-export type LinkId = number
+export type LinkId = UniqueId<number, 'LinkId'>
 
 export type SerialisedLLinkArray = [
   id: LinkId,
@@ -90,7 +92,7 @@ type BasicReadonlyNetwork = Pick<
 >
 
 // this is the class in charge of storing link information
-export class LLink implements LinkSegment, Serialisable<SerialisableLLink> {
+export class LLink implements ILinkSegment, Serialisable<SerialisableLLink> {
   static _drawDebug = false
 
   /** Link ID */

src/lib/litegraph/src/Reroute.ts

@@ -6,21 +6,22 @@ import type { LGraphNode, NodeId } from './LGraphNode'
 import { LLink, type LinkId } from './LLink'
 import type {
   CanvasColour,
+  ILinkSegment,
   INodeInputSlot,
   INodeOutputSlot,
   LinkNetwork,
-  LinkSegment,
   Point,
   Positionable,
   ReadOnlyRect,
-  ReadonlyLinkNetwork
+  ReadonlyLinkNetwork,
+  UniqueId
 } from './interfaces'
 import { distance, isPointInRect } from './measure'
 import type { Serialisable, SerialisableReroute } from './types/serialisation'
 
 const layoutMutations = useLayoutMutations()
 
-export type RerouteId = number
+export type RerouteId = UniqueId<number, 'RerouteId'>
 
 /** The input or output slot that an incomplete reroute link is connected to. */
 export interface FloatingRerouteSlot {
@@ -36,7 +37,7 @@ export interface FloatingRerouteSlot {
  * and a `WeakRef` to a {@link LinkNetwork} to resolve them.
  */
 export class Reroute
-  implements Positionable, LinkSegment, Serialisable<SerialisableReroute>
+  implements Positionable, ILinkSegment, Serialisable<SerialisableReroute>
 {
   static radius: number = 10
   /** Maximum distance from reroutes to their bezier curve control points. */

src/lib/litegraph/src/interfaces.ts

@@ -11,6 +11,9 @@ import type { SubgraphOutputNode } from './subgraph/SubgraphOutputNode'
 import type { LinkDirection, RenderShape } from './types/globalEnums'
 import type { IBaseWidget } from './types/widgets'
 
+declare const __brand: unique symbol
+export type UniqueId<T, B> = T & { [__brand]?: B }
+
 export type Dictionary<T> = { [key: string]: T }
 
 /** Allows all properties to be null.  The same as `Partial<T>`, but adds null instead of undefined. */
@@ -183,8 +186,10 @@ export interface ItemLocator {
   ): SubgraphInputNode | SubgraphOutputNode | undefined
 }
 
+export type LinkSegment = Reroute | LLink
+
 /** Contains a cached 2D canvas path and a centre point, with an optional forward angle. */
-export interface LinkSegment {
+export interface ILinkSegment {
   /** Link / reroute ID */
   readonly id: LinkId | RerouteId
   /** The {@link id} of the reroute that this segment starts from (output side), otherwise `undefined`.  */

src/platform/workflow/management/stores/workflowStore.ts

@@ -182,14 +182,14 @@ interface WorkflowStore {
   activeSubgraph: Subgraph | undefined
   /** Updates the {@link subgraphNamePath} and {@link isSubgraphActive} values. */
   updateActiveGraph: () => void
-  executionIdToCurrentId: (id: string) => any
+  executionIdToCurrentId: (id: NodeExecutionId) => any
   nodeIdToNodeLocatorId: (nodeId: NodeId, subgraph?: Subgraph) => NodeLocatorId
   nodeExecutionIdToNodeLocatorId: (
-    nodeExecutionId: NodeExecutionId | string
+    nodeExecutionId: NodeExecutionId
   ) => NodeLocatorId | null
-  nodeLocatorIdToNodeId: (locatorId: NodeLocatorId | string) => NodeId | null
+  nodeLocatorIdToNodeId: (locatorId: NodeLocatorId) => NodeId | null
   nodeLocatorIdToNodeExecutionId: (
-    locatorId: NodeLocatorId | string,
+    locatorId: NodeLocatorId,
     targetSubgraph?: Subgraph
   ) => NodeExecutionId | null
 }
@@ -518,14 +518,14 @@ export const useWorkflowStore = defineStore('workflow', () => {
     isSubgraphActive.value = isSubgraph(subgraph)
   }
 
-  const subgraphNodeIdToSubgraph = (id: string, graph: LGraph | Subgraph) => {
+  const subgraphNodeIdToSubgraph = (id: NodeId, graph: LGraph | Subgraph) => {
     const node = graph.getNodeById(id)
     if (node?.isSubgraphNode()) return node.subgraph
   }
 
   const getSubgraphsFromInstanceIds = (
     currentGraph: LGraph | Subgraph,
-    subgraphNodeIds: string[],
+    subgraphNodeIds: NodeId[],
     subgraphs: Subgraph[] = []
   ): Subgraph[] => {
     const currentPart = subgraphNodeIds.shift()
@@ -538,7 +538,7 @@ export const useWorkflowStore = defineStore('workflow', () => {
     return getSubgraphsFromInstanceIds(subgraph, subgraphNodeIds, subgraphs)
   }
 
-  const executionIdToCurrentId = (id: string) => {
+  const executionIdToCurrentId = (id: NodeExecutionId) => {
     const subgraph = activeSubgraph.value
 
     // Short-circuit: ID belongs to the parent workflow / no active subgraph
@@ -588,11 +588,11 @@ export const useWorkflowStore = defineStore('workflow', () => {
    * @returns The NodeLocatorId or null if conversion fails
    */
   const nodeExecutionIdToNodeLocatorId = (
-    nodeExecutionId: NodeExecutionId | string
+    nodeExecutionId: NodeExecutionId
   ): NodeLocatorId | null => {
     // Handle simple node IDs (root graph - no colons)
     if (!nodeExecutionId.includes(':')) {
-      return nodeExecutionId
+      return nodeExecutionId as NodeLocatorId
     }
 
     const parts = parseNodeExecutionId(nodeExecutionId)
@@ -623,9 +623,7 @@ export const useWorkflowStore = defineStore('workflow', () => {
    * @param locatorId The NodeLocatorId
    * @returns The local node ID or null if invalid
    */
-  const nodeLocatorIdToNodeId = (
-    locatorId: NodeLocatorId | string
-  ): NodeId | null => {
+  const nodeLocatorIdToNodeId = (locatorId: NodeLocatorId): NodeId | null => {
     const parsed = parseNodeLocatorId(locatorId)
     return parsed?.localNodeId ?? null
   }
@@ -637,7 +635,7 @@ export const useWorkflowStore = defineStore('workflow', () => {
    * @returns The execution ID or null if the node is not accessible from the target context
    */
   const nodeLocatorIdToNodeExecutionId = (
-    locatorId: NodeLocatorId | string,
+    locatorId: NodeLocatorId,
     targetSubgraph?: Subgraph
   ): NodeExecutionId | null => {
     const parsed = parseNodeLocatorId(locatorId)

src/services/litegraphService.ts

@@ -151,8 +151,9 @@ export const useLitegraphService = () => {
        */
       #setupStrokeStyles() {
         this.strokeStyles['running'] = function (this: LGraphNode) {
-          const nodeId = String(this.id)
-          const nodeLocatorId = useWorkflowStore().nodeIdToNodeLocatorId(nodeId)
+          const nodeLocatorId = useWorkflowStore().nodeIdToNodeLocatorId(
+            this.id
+          )
           const state =
             useExecutionStore().nodeLocationProgressStates[nodeLocatorId]?.state
           if (state === 'running') {
@@ -376,7 +377,7 @@ export const useLitegraphService = () => {
     node.title = nodeDef.display_name || nodeDef.name
   }
 
-  async function registerNodeDef(nodeId: string, nodeDefV1: ComfyNodeDefV1) {
+  async function registerNodeDef(type: string, nodeDefV1: ComfyNodeDefV1) {
     const node = class ComfyNode extends LGraphNode {
       static comfyClass: string
       static override title: string
@@ -416,8 +417,9 @@ export const useLitegraphService = () => {
        */
       #setupStrokeStyles() {
         this.strokeStyles['running'] = function (this: LGraphNode) {
-          const nodeId = String(this.id)
-          const nodeLocatorId = useWorkflowStore().nodeIdToNodeLocatorId(nodeId)
+          const nodeLocatorId = useWorkflowStore().nodeIdToNodeLocatorId(
+            this.id
+          )
           const state =
             useExecutionStore().nodeLocationProgressStates[nodeLocatorId]?.state
           if (state === 'running') {
@@ -649,7 +651,7 @@ export const useLitegraphService = () => {
 
     const nodeDef = new ComfyNodeDefImpl(nodeDefV1)
     node.nodeData = nodeDef
-    LiteGraph.registerNodeType(nodeId, node)
+    LiteGraph.registerNodeType(type, node)
     // Note: Do not following assignments before `LiteGraph.registerNodeType`
     // because `registerNodeType` will overwrite the assignments.
     node.category = nodeDef.category

src/stores/executionStore.ts

@@ -28,7 +28,7 @@ import type {
 import { api } from '@/scripts/api'
 import { app } from '@/scripts/app'
 import { useNodeOutputStore } from '@/stores/imagePreviewStore'
-import type { NodeLocatorId } from '@/types/nodeIdentification'
+import type { NodeExecutionId, NodeLocatorId } from '@/types/nodeIdentification'
 import { createNodeLocatorId } from '@/types/nodeIdentification'
 
 interface QueuedPrompt {
@@ -78,8 +78,10 @@ function getSubgraphsFromInstanceIds(
  * @param nodeId The node ID from execution context (could be execution ID)
  * @returns The NodeLocatorId
  */
-function executionIdToNodeLocatorId(nodeId: string | number): NodeLocatorId {
-  const nodeIdStr = String(nodeId)
+function executionIdToNodeLocatorId(
+  executionId: NodeExecutionId
+): NodeLocatorId {
+  const nodeIdStr = String(executionId)
 
   if (!nodeIdStr.includes(':')) {
     // It's a top-level node ID

src/types/nodeIdentification.ts

@@ -1,3 +1,4 @@
+import type { UniqueId } from '@/lib/litegraph/src/interfaces'
 import type { NodeId } from '@/platform/workflow/validation/schemas/workflowSchema'
 
 /**
@@ -15,7 +16,7 @@ import type { NodeId } from '@/platform/workflow/validation/schemas/workflowSche
  * Unlike execution IDs which change based on the instance path,
  * NodeLocatorId remains the same for all instances of a particular node.
  */
-export type NodeLocatorId = string
+export type NodeLocatorId = UniqueId<string, 'NodeLocatorId'>
 
 /**
  * An execution identifier representing a node's position in nested subgraphs.
@@ -24,7 +25,8 @@ export type NodeLocatorId = string
  * Format: Colon-separated path of node IDs
  * Example: "123:456:789" (node 789 in subgraph 456 in subgraph 123)
  */
-export type NodeExecutionId = string
+declare const __executionIdBrand: unique symbol
+export type NodeExecutionId = UniqueId<string, 'NodeExecutionId'>
 
 /**
  * Type guard to check if a value is a NodeLocatorId
@@ -105,7 +107,7 @@ export function createNodeLocatorId(
  * @param id The NodeExecutionId to parse
  * @returns Array of node IDs from root to target, or null if not an execution ID
  */
-export function parseNodeExecutionId(id: string): NodeId[] | null {
+export function parseNodeExecutionId(id: NodeExecutionId): NodeId[] | null {
   if (!isNodeExecutionId(id)) return null
 
   return id