fix(core): Fix memory issue with empty model response (#11300)

package.json

@@ -87,7 +87,8 @@
       "[email protected]": "patches/[email protected]",
       "@types/[email protected]": "patches/@[email protected]",
       "@types/[email protected]": "patches/@[email protected]",
-      "@types/[email protected]": "patches/@[email protected]"
+      "@types/[email protected]": "patches/@[email protected]",
+      "@langchain/[email protected]": "patches/@[email protected]"
     }
   }
 }

patches/@langchain__core@0.3.3.patch

@@ -0,0 +1,26 @@
+diff --git a/dist/memory.cjs b/dist/memory.cjs
+index f5bceead9a5533ff71e0c6f6960384ced2ee0060..5085269a58493c29e36ea7384368cd64a0e979a5 100644
+--- a/dist/memory.cjs
++++ b/dist/memory.cjs
+@@ -41,7 +41,7 @@ exports.getInputValue = getInputValue;
+  */
+ const getOutputValue = (outputValues, outputKey) => {
+     const value = getValue(outputValues, outputKey);
+-    if (!value) {
++    if (!value && value !== '') {
+         const keys = Object.keys(outputValues);
+         throw new Error(`output values have ${keys.length} keys, you must specify an output key or pass only 1 key as output`);
+     }
+diff --git a/dist/memory.js b/dist/memory.js
+index 8e221f55b151d0ff7592b30ca34363b9ec577e01..a3ff2a514eda6c7e606e8f6d7305535b29ab671e 100644
+--- a/dist/memory.js
++++ b/dist/memory.js
+@@ -36,7 +36,7 @@ export const getInputValue = (inputValues, inputKey) => {
+  */
+ export const getOutputValue = (outputValues, outputKey) => {
+     const value = getValue(outputValues, outputKey);
+-    if (!value) {
++    if (!value && value !== '') {
+         const keys = Object.keys(outputValues);
+         throw new Error(`output values have ${keys.length} keys, you must specify an output key or pass only 1 key as output`);
+     }