test(s3/lifecycle): integration coverage for DeleteBucketLifecycle stops dispatching

Operator UX: after DeleteBucketLifecycle, the worker must observe the
removal on the next sweep and stop expiring objects under the now-gone
rule. A regression that caches old configs across
PutBucketLifecycleConfiguration → DeleteBucketLifecycle would keep
silently dropping objects.

Setup: positive control (rule active, backdated obj expires) →
DeleteBucketLifecycle → PUT + backdate a fresh object → second
sweep. The fresh object must remain.

test/s3/lifecycle/s3_lifecycle_delete_config_test.go

@@ -0,0 +1,67 @@
+// Operator-removes-lifecycle-config integration scenario.
+package lifecycle
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/aws/aws-sdk-go-v2/aws"
+	"github.com/aws/aws-sdk-go-v2/service/s3"
+	"github.com/stretchr/testify/require"
+)
+
+// TestLifecycleDeleteBucketLifecycleStopsDispatching: when an operator
+// runs DeleteBucketLifecycle, subsequent sweeps must NOT continue
+// expiring objects under the now-removed rule. The worker reads each
+// bucket's XML config from filer state on every run; if it cached the
+// previous config across PutBucketLifecycleConfiguration → DeleteBucket
+// Lifecycle the bucket would keep losing objects.
+//
+// Setup: positive control (rule active, backdated obj expires), then
+// DeleteBucketLifecycle, then PUT + backdate a fresh object, run the
+// worker again. The fresh object must remain — no rule, no dispatch.
+func TestLifecycleDeleteBucketLifecycleStopsDispatching(t *testing.T) {
+	c := s3Client(t)
+	fc, fcClose := filerClient(t)
+	defer fcClose()
+
+	bucket := uniqueBucket("delete-config")
+	mustCreateBucket(t, c, bucket)
+	putExpirationLifecycle(t, c, bucket, "x/", 1)
+
+	const firstKey = "x/initial.txt"
+	putObject(t, c, bucket, firstKey, "first")
+	backdateMtime(t, fc, bucket, firstKey, 30)
+
+	out := runLifecycleShard(t)
+	t.Logf("sweep 1 output (rule active):\n%s", out)
+	require.Eventuallyf(t, func() bool {
+		_, err := c.HeadObject(context.Background(), &s3.HeadObjectInput{
+			Bucket: aws.String(bucket), Key: aws.String(firstKey),
+		})
+		return isS3NotFound(err)
+	}, 30*time.Second, 500*time.Millisecond, "positive control: %s should expire while rule is active", firstKey)
+
+	// Now remove the rule. The worker must observe the removal on the
+	// next sweep.
+	_, err := c.DeleteBucketLifecycle(context.Background(), &s3.DeleteBucketLifecycleInput{
+		Bucket: aws.String(bucket),
+	})
+	require.NoError(t, err)
+
+	const survivorKey = "x/post-delete.txt"
+	putObject(t, c, bucket, survivorKey, "should-stay")
+	backdateMtime(t, fc, bucket, survivorKey, 30)
+
+	out = runLifecycleShard(t)
+	t.Logf("sweep 2 output (rule deleted):\n%s", out)
+
+	// Wait the same window; survivor MUST still exist after the worker
+	// has had every opportunity to (incorrectly) act on it.
+	time.Sleep(2 * time.Second)
+	_, err = c.HeadObject(context.Background(), &s3.HeadObjectInput{
+		Bucket: aws.String(bucket), Key: aws.String(survivorKey),
+	})
+	require.NoError(t, err, "after DeleteBucketLifecycle, sweeps must not expire %s", survivorKey)
+}