Fix lint, add Node 18 fallback

langchain-core/src/runnables/base.ts

@@ -920,11 +920,33 @@ export abstract class Runnable<
     const outerThis = this;
     async function consumeRunnableStream() {
       try {
+        let signal;
+        if (options?.signal) {
+          if ("any" in AbortSignal) {
+            // Use native AbortSignal.any() if available (Node 19+)
+            // eslint-disable-next-line @typescript-eslint/no-explicit-any
+            signal = (AbortSignal as any).any([
+              abortController.signal,
+              options.signal,
+            ]);
+          } else {
+            // Fallback for Node 18 and below - just use the provided signal
+            signal = options.signal;
+            // Ensure we still abort our controller when the parent signal aborts
+            options.signal.addEventListener(
+              "abort",
+              () => {
+                abortController.abort();
+              },
+              { once: true }
+            );
+          }
+        } else {
+          signal = abortController.signal;
+        }
         const runnableStream = await outerThis.stream(input, {
           ...config,
-          signal: options?.signal
-            ? AbortSignal.any([options.signal, abortController.signal])
-            : abortController.signal,
+          signal,
         });
         const tappedStream = eventStreamer.tapOutputIterable(
           runId,

langchain-core/src/runnables/tests/runnable_stream_events_v2.test.ts

@@ -2271,6 +2271,7 @@ test("streamEvents method handles errors", async () => {
   });
 
   try {
+    // eslint-disable-next-line no-unreachable-loop
     for await (const _ of model.streamEvents("Hello! Tell me about yourself.", {
       version: "v2",
     })) {