add max inbout size validation spec

src/index.ts

@@ -912,11 +912,19 @@ export class GossipSub extends EventEmitter<GossipsubEvents> implements Initiali
         }
       })
     } catch (err) {
-      this.log.error(err)
-      this.onPeerDisconnected(peerId)
+      this.handlePeerReadStreamError(err as Error, peerId)
     }
   }
 
+  /**
+   * Handle error when read stream pipe throws, less of the functional use but more
+   * to for testing purposes to spy on the error handling
+   * */
+  private handlePeerReadStreamError(err: Error, peerId: PeerId): void {
+    this.log.error(err)
+    this.onPeerDisconnected(peerId)
+  }
+
   /**
    * Handles an rpc request from a peer
    */

test/gossip.spec.ts

@@ -24,7 +24,8 @@ describe('gossip', () => {
       init: {
         scoreParams: {
           IPColocationFactorThreshold: GossipsubDhi + 3
-        }
+        },
+        maxInboundDataLength: 4000000
       }
     })
   })
@@ -78,6 +79,38 @@ describe('gossip', () => {
     nodeASpy.pushGossip.restore()
   })
 
+  it('should reject incoming messages bigger than maxInboundDataLength limit', async function () {
+    this.timeout(10e4)
+    const nodeA = nodes[0]
+    const nodeB = nodes[1]
+
+    const twoNodes = [nodeA, nodeB]
+    const topic = 'Z'
+    // add subscriptions to each node
+    twoNodes.forEach((n) => n.getPubSub().subscribe(topic))
+
+    // every node connected to every other
+    await connectAllPubSubNodes(twoNodes)
+
+    // wait for subscriptions to be transmitted
+    await Promise.all(twoNodes.map(async (n) => await pEvent(n.getPubSub(), 'subscription-change')))
+
+    // await mesh rebalancing
+    await Promise.all(twoNodes.map(async (n) => await pEvent(n.getPubSub(), 'gossipsub:heartbeat')))
+
+    // set spy. NOTE: Forcing private property to be public
+    const nodeBSpy = nodeB.getPubSub() as Partial<GossipSub> as SinonStubbedInstance<{
+      handlePeerReadStreamError: GossipSub['handlePeerReadStreamError']
+    }>
+    sinon.spy(nodeBSpy, 'handlePeerReadStreamError')
+
+    // This should lead to handlePeerReadStreamError at nodeB
+    await nodeA.getPubSub().publish(topic, new Uint8Array(5000000))
+    await pEvent(nodeA.getPubSub(), 'gossipsub:heartbeat')
+    const expectedError = nodeBSpy.handlePeerReadStreamError.getCalls()[0]?.args[0]
+    expect(expectedError !== undefined && (expectedError as unknown as { code: string }).code, 'ERR_MSG_DATA_TOO_LONG')
+  })
+
   it('should send piggyback control into other sent messages', async function () {
     this.timeout(10e4)
     const nodeA = nodes[0]