From 3b822db81268e2370bd7c94bdf10ae9426c1db93 Mon Sep 17 00:00:00 2001
From: Arman Yaraee <arman.yaraee@deversifi.com>
Date: Tue, 14 Apr 2026 16:42:28 +0100
Subject: [PATCH] bug: (@effect/cluster): Add reproduction test case for
 infinite recursion

Cluster rpc serialization causes a full infinite recursion
Issue is on cluster/src/Runners.ts around L595 where the envelope's message is not encoded or for some reason the raw BigDecimal object is being packed instead of the encoded message
---
 packages/cluster/test/SocketRunner.test.ts | 115 +++++++++++++++++++++
 1 file changed, 115 insertions(+)
 create mode 100644 packages/cluster/test/SocketRunner.test.ts

diff --git a/packages/cluster/test/SocketRunner.test.ts b/packages/cluster/test/SocketRunner.test.ts
new file mode 100644
index 00000000000..8b2ee1fd36d
--- /dev/null
+++ b/packages/cluster/test/SocketRunner.test.ts
@@ -0,0 +1,115 @@
+import { ClusterSchema, Entity, MessageStorage, RunnerAddress, RunnerStorage, ShardingConfig } from "@effect/cluster"
+import { NodeClusterSocket } from "@effect/platform-node"
+import { Rpc, RpcSerialization } from "@effect/rpc"
+import { describe, it } from "@effect/vitest"
+import { BigDecimal, Effect, Layer, Logger, LogLevel, Option, PrimaryKey, Schema } from "effect"
+import * as RunnerHealth from "../src/RunnerHealth.js"
+import * as SocketRunner from "../src/SocketRunner.js"
+
+class TestPayload extends Schema.Class<TestPayload>("TestPayload")({
+  id: Schema.String,
+  amount: Schema.BigDecimal
+}) {
+  [PrimaryKey.symbol]() {
+    return this.id
+  }
+}
+
+const TestEntity = Entity
+  .make("TestEntity", [
+    Rpc.make("Process", {
+      payload: TestPayload,
+      success: Schema.Void
+    })
+  ])
+  .annotateRpcs(ClusterSchema.Persisted, true)
+  .annotateRpcs(ClusterSchema.Uninterruptible, true)
+
+const TestEntityLayer = TestEntity.toLayer(
+  Effect.succeed({
+    Process: () => Effect.void
+  })
+)
+
+const RUNNER_PORT = 50_123
+// Build shared storage instances once, so runner and client see the same state.
+// MessageStorage.layerMemory requires ShardingConfig, so we provide a minimal one.
+const SharedStorage = Layer.mergeAll(
+  RunnerStorage.layerMemory,
+  MessageStorage.layerMemory
+).pipe(
+  Layer.provide(ShardingConfig.layerDefaults)
+)
+
+const makeRunnerLayer = (port: number) =>
+  TestEntityLayer.pipe(
+    Layer.provideMerge(SocketRunner.layer),
+    Layer.provide(RunnerHealth.layerNoop),
+    Layer.provide(NodeClusterSocket.layerSocketServer),
+    Layer.provide(NodeClusterSocket.layerClientProtocol),
+    Layer.provide(ShardingConfig.layer({
+      runnerAddress: Option.some(RunnerAddress.make("localhost", port)),
+      entityTerminationTimeout: 0,
+      entityMessagePollInterval: 5000,
+      sendRetryInterval: 100
+    })),
+    Layer.provide(RpcSerialization.layerMsgPack)
+  )
+
+const makeClientLayer = (port: number) =>
+  SocketRunner.layerClientOnly.pipe(
+    Layer.provide(NodeClusterSocket.layerClientProtocol),
+    Layer.provide(ShardingConfig.layer({
+      runnerAddress: Option.some(RunnerAddress.make("localhost", port)),
+      runnerListenAddress: Option.some(RunnerAddress.make("localhost", port)),
+      entityTerminationTimeout: 0,
+      entityMessagePollInterval: 5000,
+      sendRetryInterval: 100
+    })),
+    Layer.provide(RpcSerialization.layerMsgPack)
+  )
+
+// BigDecimal.normalize creates a circular `normalized` self-reference.
+// When a persisted message is sent with discard: true, the notify path in Runners.makeRpc
+// passes the raw envelope (with circular BigDecimal payload) to the runner via msgpack,
+// causing RangeError: Maximum call stack size exceeded.
+describe("SocketRunner", () => {
+  it.scopedLive(
+    "entity call with BigDecimal and discard should not stack overflow",
+    () =>
+      Effect.gen(function*() {
+        // Start the runner (with socket server and entity handler)
+        yield* Layer.launch(makeRunnerLayer(RUNNER_PORT)).pipe(Effect.forkScoped)
+
+        // Give the runner time to start and acquire shards
+        yield* Effect.sleep("2 seconds")
+        yield* Effect.log("Before starting the client")
+
+        // Send a message from the client with discard: true.
+        // The BigDecimal is normalized to trigger the circular `normalized` self-reference.
+        yield* Effect.gen(function*() {
+          yield* Effect.log("Starting the client")
+          yield* Effect.sleep("2 seconds")
+          const makeClient = yield* TestEntity.client
+          // Give the client time to discover the runner
+          yield* Effect.sleep("3 seconds")
+          const client = makeClient("entity-1")
+
+          const amount = BigDecimal.unsafeFromString("123.45")
+
+          yield* client.Process(
+            TestPayload.make({ id: "req-1", amount }),
+            { discard: true }
+          )
+        }).pipe(
+          Effect.provide(makeClientLayer(RUNNER_PORT)),
+          Effect.scoped
+        )
+      }).pipe(Effect.provide(
+        SharedStorage.pipe(Layer.provideMerge(
+          Logger.minimumLogLevel(LogLevel.None)
+        ))
+      )),
+    30_000
+  )
+})