fix[js]: print stack trace when error occur in evaluate

js/package.json

@@ -197,4 +197,4 @@
     },
     "./package.json": "./package.json"
   }
-}
+}

js/src/evaluation/_runner.ts

@@ -6,6 +6,7 @@
 import { AsyncCaller } from "../utils/async_caller.js";
 import { atee } from "../utils/atee.js";
 import { getLangChainEnvVarsMetadata } from "../utils/env.js";
+import { printErrorStackTrace } from "../utils/error.js";
 import { randomName } from "./_random_name.js";
 import {
   EvaluationResult,
@@ -61,8 +62,8 @@
   runs?: AsyncGenerator<Run>;
   evaluationResults?: AsyncGenerator<EvaluationResults>;
   summaryResults?: AsyncGenerator<
     (runsArray: Run[]) => AsyncGenerator<EvaluationResults, any, unknown>,
     any,
     unknown
   >;
   examples?: Example[];
@@ -141,8 +142,8 @@
   _evaluationResults?: AsyncGenerator<EvaluationResults>;
 
   _summaryResults?: AsyncGenerator<
     (runsArray: Run[]) => AsyncGenerator<EvaluationResults, any, unknown>,
     any,
     unknown
   >;
 
@@ -206,7 +207,7 @@
   get evaluationResults(): AsyncGenerator<EvaluationResults> {
     if (this._evaluationResults === undefined) {
       return async function* (this: _ExperimentManager) {
         for (const _ of await this.getExamples()) {
           yield { results: [] };
         }
       }.call(this);
@@ -538,6 +539,7 @@
         console.error(
           `Error running evaluator ${evaluator.evaluateRun.name} on run ${run.id}: ${e}`
         );
+        printErrorStackTrace(e);
       }
     }
 
@@ -619,7 +621,7 @@
             this.client._selectEvalResults(summaryEvalResult);
           aggregateFeedback.push(...flattenedResults);
           for (const result of flattenedResults) {
             const { targetRunId, ...feedback } = result;
             const evaluatorInfo = feedback.evaluatorInfo;
             delete feedback.evaluatorInfo;
 
@@ -635,6 +637,7 @@
               evaluator.name
             }: ${JSON.stringify(e, null, 2)}`
           );
+          printErrorStackTrace(e);
         }
       }
 
@@ -798,7 +801,7 @@
   return results;
 }
 
 type ForwardFn = ((...args: any[]) => Promise<any>) | ((...args: any[]) => any);
 
 async function _forward(
   fn: ForwardFn,
@@ -835,6 +838,7 @@
     await wrappedFn(example.inputs);
   } catch (e) {
     console.error(`Error running target function: ${e}`);
+    printErrorStackTrace(e);
   }
 
   if (!run) {

js/src/utils/error.ts

@@ -0,0 +1,23 @@
+function getErrorStackTrace(e: unknown) {
+  if (typeof e !== "object" || e == null) return undefined;
+  if (!("stack" in e) || typeof e.stack !== "string") return undefined;
+
+  let stack = e.stack;
+
+  const prevLine = `${e}`;
+  if (stack.startsWith(prevLine)) {
+    stack = stack.slice(prevLine.length);
+  }
+
+  if (stack.startsWith("\n")) {
+    stack = stack.slice(1);
+  }
+
+  return stack;
+}
+
+export function printErrorStackTrace(e: unknown) {
+  const stack = getErrorStackTrace(e);
+  if (stack == null) return;
+  console.error(stack);
+}