[Test] Add integration test: LGraph snapshot (#591)

- Runs basic Litegraph init before performing the snapshot
- Allows a significantly more useful verification of the public API

test/testExtensions.ts

@@ -2,14 +2,19 @@ import { test as baseTest } from "vitest"
 import type { ISerialisedGraph, SerialisableGraph } from "../src/types/serialisation"
 import { LGraph } from "@/LGraph"
 import { basicSerialisableGraph, minimalSerialisableGraph, oldSchemaGraph } from "./assets/testGraphs"
+import { LiteGraph } from "@/litegraph"
 
 interface LitegraphFixtures {
   minimalGraph: LGraph
   minimalSerialisableGraph: SerialisableGraph
-  basicSerialisableGraph: SerialisableGraph
   oldSchemaGraph: ISerialisedGraph
 }
 
+/** These fixtures alter global state, and are difficult to reset. Relies on a single test per-file to reset state. */
+interface DirtyFixtures {
+  basicSerialisableGraph: SerialisableGraph
+}
+
 export const test = baseTest.extend<LitegraphFixtures>({
   minimalGraph: async ({ }, use) => {
     // Before each test function
@@ -18,10 +23,21 @@ export const test = baseTest.extend<LitegraphFixtures>({
 
     // use the fixture value
     await use(lGraph)
-
-    // After each test function
   },
-  basicSerialisableGraph: structuredClone(basicSerialisableGraph),
   minimalSerialisableGraph: structuredClone(minimalSerialisableGraph),
   oldSchemaGraph: structuredClone(oldSchemaGraph),
 })
+
+/** Test that use {@link DirtyFixtures}. One test per file. */
+export const dirtyTest = test.extend<DirtyFixtures>({
+  basicSerialisableGraph: async ({}, use) => {
+    if (!basicSerialisableGraph.nodes) throw new Error("Invalid test object")
+
+    // Register node types
+    for (const node of basicSerialisableGraph.nodes) {
+      LiteGraph.registerNodeType(node.type!, LiteGraph.LGraphNode)
+    }
+
+    await use(structuredClone(basicSerialisableGraph))
+  },
+})