fix(batch): clear message group references after request

packages/batch/src/SqsFifoPartialProcessor.ts

@@ -92,6 +92,7 @@ class SqsFifoPartialProcessor extends BatchProcessorSync {
    */
   public processSync(): (SuccessResponse | FailureResponse)[] {
     this.prepare();
+    this.#processor.prepare();
 
     const processedRecords: (SuccessResponse | FailureResponse)[] = [];
     let currentIndex = 0;

packages/batch/src/SqsFifoPartialProcessorAsync.ts

@@ -91,6 +91,7 @@ class SqsFifoPartialProcessorAsync extends BatchProcessor {
    */
   public async process(): Promise<(SuccessResponse | FailureResponse)[]> {
     this.prepare();
+    this.#processor.prepare();
 
     const processedRecords: (SuccessResponse | FailureResponse)[] = [];
     let currentIndex = 0;

packages/batch/src/SqsFifoProcessor.ts

@@ -32,6 +32,14 @@ class SqsFifoProcessor {
     this.#failedGroupIds.add(group);
   }
 
+  /**
+   * Prepares the processor for a new batch of messages.
+   */
+  public prepare(): void {
+    this.#currentGroupId = undefined;
+    this.#failedGroupIds.clear();
+  }
+
   /**
    * Sets the current group ID for the message being processed.
    *

packages/batch/tests/unit/SqsFifoPartialProcessor.test.ts

@@ -185,4 +185,40 @@ describe('SQS FIFO Processors', () => {
       });
     });
   }
+
+  it('continues processing and moves to the next group when `skipGroupOnError` is true', async () => {
+    // Prepare
+    const firstRecord = sqsRecordFactory('fail', '1');
+    const secondRecord = sqsRecordFactory('success', '2');
+    const firstRecordAgain = sqsRecordFactory('success', '1');
+    const event1 = {
+      Records: [firstRecord, secondRecord],
+    };
+    const event2 = {
+      Records: [firstRecordAgain],
+    };
+    const processor = new SqsFifoPartialProcessor();
+    const fn = vi.fn((record) => {
+      if (record.body.includes('fail')) {
+        throw new Error('Processing failed');
+      }
+
+      return record;
+    });
+
+    // Act
+    const result1 = processPartialResponseSync(event1, fn, processor, {
+      skipGroupOnError: true,
+      throwOnFullBatchFailure: false,
+    });
+    const result2 = processPartialResponseSync(event2, fn, processor, {
+      skipGroupOnError: true,
+      throwOnFullBatchFailure: false,
+    });
+
+    // Assess
+    expect(result1.batchItemFailures.length).toBe(1);
+    expect(result2.batchItemFailures.length).toBe(0);
+    expect(fn).toHaveBeenCalledTimes(3);
+  });
 });