fix(assistants): correctly accumulate tool calls when streaming (#1031)

* fix(accumulateDelta): AssistantStream accumulateDelta toolCall (#771)

* minor style changes

---------

Co-authored-by: A4F54B <runesformempool@outlook.com>

src/lib/AssistantStream.ts

@@ -684,6 +684,30 @@ export class AssistantStream
  accValue.push(...deltaValue); // Use spread syntax for efficient addition
  continue;
  }
+
+ for (const deltaEntry of deltaValue) {
+ if (!Core.isObj(deltaEntry)) {
+ throw new Error(`Expected array delta entry to be an object but got: ${deltaEntry}`);
+ }
+
+ const index = deltaEntry['index'];
+ if (index == null) {
+ console.error(deltaEntry);
+ throw new Error('Expected array delta entry to have an `index` property');
+ }
+
+ if (typeof index !== 'number') {
+ throw new Error(`Expected array delta entry \`index\` property to be a number but got ${index}`);
+ }
+
+ const accEntry = accValue[index];
+ if (accEntry == null) {
+ accValue.push(deltaEntry);
+ } else {
+ accValue[index] = this.accumulateDelta(accEntry, deltaEntry);
+ }
+ }
+ continue;
  } else {
  throw Error(`Unhandled record type: ${key}, deltaValue: ${deltaValue}, accValue: ${accValue}`);
  }