Improve execution logic / Fix group node execution (#4422)

src/utils/executableGroupNodeDto.ts

@@ -0,0 +1,71 @@
+import {
+  type ExecutableLGraphNode,
+  ExecutableNodeDTO,
+  type ISlotType,
+  LGraphEventMode,
+  type LGraphNode
+} from '@comfyorg/litegraph'
+
+export const GROUP = Symbol()
+
+export function isGroupNode(node: LGraphNode): boolean {
+  return node.constructor?.nodeData?.[GROUP] !== undefined
+}
+
+export class ExecutableGroupNodeDTO extends ExecutableNodeDTO {
+  override get isVirtualNode(): true {
+    return true
+  }
+
+  override getInnerNodes(): ExecutableLGraphNode[] {
+    return this.node.getInnerNodes?.(this.nodesByExecutionId) ?? []
+  }
+
+  override resolveOutput(slot: number, type: ISlotType, visited: Set<string>) {
+    // Temporary duplication: Bypass nodes are bypassed using the first input with matching type
+    if (this.mode === LGraphEventMode.BYPASS) {
+      const { inputs } = this
+
+      // Bypass nodes by finding first input with matching type
+      const parentInputIndexes = Object.keys(inputs).map(Number)
+      // Prioritise exact slot index
+      const indexes = [slot, ...parentInputIndexes]
+      const matchingIndex = indexes.find((i) => inputs[i]?.type === type)
+
+      // No input types match
+      if (matchingIndex === undefined) return
+
+      return this.resolveInput(matchingIndex, visited)
+    }
+
+    const linkId = this.node.outputs[slot]?.links?.at(0)
+    const link = this.node.graph?.getLink(linkId)
+    if (!link) {
+      throw new Error(
+        `Failed to get link for group node ${this.node.id} with link ${linkId}`
+      )
+    }
+
+    const updated = this.node.updateLink?.(link)
+    if (!updated) {
+      throw new Error(
+        `Failed to update link for group node ${this.node.id} with link ${linkId}`
+      )
+    }
+
+    const node = this.node
+      .getInnerNodes?.(this.nodesByExecutionId)
+      .find((node) => node.id === updated.origin_id)
+    if (!node) {
+      throw new Error(
+        `Failed to get node for group node ${this.node.id} with link ${linkId}`
+      )
+    }
+
+    return {
+      node,
+      origin_id: `${this.id}:${(updated.origin_id as string).split(':').at(-1)}`,
+      origin_slot: updated.origin_slot
+    }
+  }
+}